84 pubblicazioni classificate nel seguente modo:

Composite fatigue failure of cold recycled material mixtures: new insights into the role of bitumen and cement
MATERIALS AND STRUCTURES
Autore/i: Graziani, Andrea; Spadoni, Sara; Ingrassia, LORENZO PAOLO; Virgili, Amedeo; Canestrari, Francesco
Classificazione: 1 Contributo su Rivista
Abstract: In pavement engineering, cold recycled material (CRM) mixtures allow implementing circular economy concepts by maximizing the reuse of reclaimed asphalt without heating. Along with bitumen emulsion and foamed bitumen, Portland cement is often added to CRM mixtures to improve the field performance. However, the role of cement on the fatigue failure is not sufficiently investigated. The objective of this research is to provide new insights into the fatigue failure of CRM mixtures produced with bitumen emulsion and cement. To this aim, two CRM mixtures prepared with different dosages of cement (1 and 2%) were subjected to uniaxial cyclic tension fatigue tests. Empirical and energy-based failure criteria, originally developed for asphalt concrete mixtures, were used to define the fatigue failure. The results showed that the fatigue failure mechanism of CRM mixtures was of a composite type, affected by both cementitious and bituminous bonds. A new criterion was proposed to identify the failure of the cementitious bonds.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/325582

A prediction model for top-down cracking in asphalt pavements with open-graded friction course
TRA Lisbon 2022 Conference Proceedings Transport Research Arena (TRA Lisbon 2022),14th-17th November 2022, Lisboa, Portugal
Autore/i: Ingrassia, LORENZO PAOLO; Virgili, Amedeo; Canestrari, Francesco
Editore: Elsevier
Classificazione: 4 Contributo in Atti di Convegno (Proceeding)
Abstract: Thick asphalt pavements with open-graded friction course (OGFC) are subjected to top-down cracking (TDC), a distress consisting of cracks that initiate on the pavement surface close to the wheelpath and propagate downwards. However, road agencies do not yet have adequate tools to predict TDC. The objective of this study was to develop a practical and reliable model to predict TDC depth evolution in such pavements. The proposed model provides a maximum TDC depth that can potentially occur in a pavement characterized by certain mechanical properties and traffic at the time of interest. The model was calibrated and validated considering several Italian motorway pavements affected by TDC based on limited data, therefore more data should be collected in the future. This model can be used in a pavement management system (PMS) to plan timely surface maintenance against TDC.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/325613

Prediction of the Long-Term Performance of an Existing Warm Recycled Motorway Pavement
MATERIALS
Autore/i: Ingrassia, L. P.; Spadoni, S.; Ferrotti, G.; Virgili, A.; Canestrari, F.
Classificazione: 1 Contributo su Rivista
Abstract: Warm mix asphalt (WMA) technologies allow the production, lay-down and compaction of asphalt mixtures at reduced temperatures and the use of higher amounts of reclaimed asphalt pavement (RAP) with respect to conventional hot mix asphalt (HMA), leading to significant environmental benefits and energy savings. However, limited data is available on the long-term performance of such pavements. The objective of this study was to predict the long-term performance of an existing warm recycled motorway pavement (made with WMA mixtures containing RAP) constructed in 2016 in central Italy, along with the corresponding hot recycled pavement (made with HMA mixtures containing RAP). For this purpose, cores were taken from the pavements in 2022 to investigate the binder and base courses through dynamic modulus and cyclic fatigue tests, according to the simplified viscoelastic continuum damage (S-VECD) testing approach. The results of the tests were used to predict the service life of the pavements using two pieces of software, KENPAVE and FlexPAVE, based respectively on the elastic design method and the viscoelastic design method in the presence of damage. The FlexPAVE results indicated that the expected service life of the WMA pavement is much longer than that of the HMA pavement, mainly because the WMA mixtures have better damage properties than the HMA mixtures. Conversely, the KENPAVE simulations predicted a similar service life for the two pavements, highlighting the impossibility of the elastic method to catch the actual contribution of high-performance non-standard materials. The promising outcomes of the FlexPAVE simulations further encourage the application of warm recycled pavements.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/311529

Evaluation of complex modulus and fatigue properties of cold recycled material mixtures using small-scale specimens
ROAD MATERIALS AND PAVEMENT DESIGN
Autore/i: Grilli, V; Virgili, A; Graziani, A
Classificazione: 1 Contributo su Rivista
Abstract: The laboratory mechanical characterisation of cold recycled materials mixtures is necessary to develop mechanistic-empirical design methods for cold recycled pavements. The present paper describes a laboratory experiment where small-scale specimens were used to characterise the complex modulus and fatigue properties of cement bitumen treated materials (CBTM) manufactured with bitumen emulsion and cement. In particular, CBTM specimens with diameter of 38 mm were tested and compared with two group of specimens with diameters of 100 and 75 mm. The complex modulus was measured by means of cyclic compression tests and then rheological modelling was applied. Fatigue tests were carried out in direct tension mode of loading. All tests were carried out at long-term curing conditions. Results and statistical analysis showed that the complex modulus values measured on large specimens (diameter of 100 and 75 mm), were not significantly different. On the other hand, the stiffness modulus values measured on small specimens (diameter of 38) were about 15% lower.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/325617

On the densification of cold recycled asphalt mixtures
JOURNAL OF TESTING AND EVALUATION
Autore/i: Mignini, C.; Virgili, A.; Graziani, A.
Classificazione: 1 Contributo su Rivista
Abstract: The mechanical behavior of cold recycled asphalt mixtures (CRAMs) is directly connected to their volumetric properties. Therefore, the objective of the present research was to investigate the effect of different composition factors on the densification of CRAMs. To this aim, a new empirical modeling approach for characterizing and comparing the densification of CRAMs using the gyratory compactor was proposed. The methodology was then applied to CRAMs produced using four gradations, two asphalt emulsions, two cements, various water contents, and several superplasticizer dosages. The densification curves were analyzed using three parameters representing the self-densification, the compactability, and the compaction energy. These parameters were linked using a mathematical model, which was represented using three interrelated pairwise relationships. The results showed that the grading distribution of the CRAMs was the main parameter controlling their densification behavior, whereas the water content and other composition factors played a minor role.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/292744

A semi-empirical model for top-down cracking depth evolution in thick asphalt pavements with open-graded friction courses
JOURNAL OF TRAFFIC AND TRANSPORTATION ENGINEERING
Autore/i: Canestrari, F.; Ingrassia, L. P.; Virgili, A.
Classificazione: 1 Contributo su Rivista
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/311531

Influence of geocomposite properties on the crack propagation and interlayer bonding of asphalt pavements
MATERIALS
Autore/i: Spadoni, S.; Ingrassia, L. P.; Paoloni, G.; Virgili, A.; Canestrari, F.
Classificazione: 1 Contributo su Rivista
Abstract: The application of geocomposites as reinforcement in asphalt pavements is a promising solution for the maintenance/rehabilitation of existing pavements and for the construction of new pavements, whose effectiveness strongly depends on the physical and mechanical properties of the geocomposite. This study aims at assessing the influence of four different geocomposites, obtained by combining a reinforcing geosynthetic with a bituminous membrane, on the crack propagation and interlayer bonding of asphalt pavements. First, a laboratory investigation was carried out on double-layered asphalt specimens. The crack propagation resistance under static and dynamic loads was investigated through three-point bending tests (carried out on specimens with and without notch) and reflective cracking tests respectively, whereas the interlayer shear strength was evaluated through Leutner tests. Then, a trial section was constructed along an Italian motorway and a Falling Weight Deflectometer (FWD) testing campaign was carried out. The laboratory investigation highlighted that—as compared to the unreinforced system—the geocomposites increased the crack propagation energy in the layer above the reinforcement from five to ten times, indicating that they can significantly extend the service life of the pavement by delaying bottom-up and reflective cracking. However, they also worsened the interlayer bonding between the asphalt layers (de-bonding effect). The field investigation indicated that all geocomposites decreased the stiffness of the asphalt layers with respect to the unreinforced pavement as a consequence of the de-bonding effect, thus corroborating the laboratory results. Based on the results obtained, it is desirable that the geocomposite possess a high energy dissipation capability and an upper coating ensuring good adhesion between the asphalt layers. The monitoring of the existing trial section in the future will provide useful data on the long-term field performance of reinforced pavements subjected to actual motorway traffic.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/295113

Mechanical Characterization and Chemical Identification of Clear Binders for Road Surface Courses
ADVANCES IN MATERIALS SCIENCE AND ENGINEERING
Autore/i: Grilli, A.; Bocci, M.; Virgili, A.; Conti, C.
Classificazione: 1 Contributo su Rivista
Abstract: The development of non-black asphalt mixtures for surface courses may play a significant role to improve functional, aesthetic and environmental issues of road pavements. Nowadays, the development of clear binders as substitutes for traditional bitumen in asphalt mixtures, which combine durability and mechanical properties, exalting the color of pavements for a better integration of road networks in urban and environmentally sensitive areas, is undoubtedly a timing challenge. However, the selection and classification of clear binders are often based only on color and standard requirements referred to traditional bitumen that do not describe consistently the binder behavior. A better understanding on clear binder properties is required to guide the aggregate selection and the mix design for surface layer, merging safety, aesthetical and environmental benefits into long lasting pavement. This paper presents a comprehensive experimental program, including empirical tests, infrared spectrum analysis, and rheological testing over a wide range of temperature and frequency, to determine the overall mechanical behavior of three clear binders. Results highlighted that the selected clear binders differ from traditional bitumen in terms of mechanical behavior. Different composition or origin can induce to completely different performance. Moreover, the combination of several testing procedures allowed suggesting specific application methods and uses for the three clear binders.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/288101

Effect of geocomposite reinforcement on the performance of thin asphalt pavements: Accelerated pavement testing and laboratory analysis
CASE STUDIES IN CONSTRUCTION MATERIALS
Autore/i: Ingrassia, L. P.; Virgili, A.; Canestrari, F.
Classificazione: 1 Contributo su Rivista
Abstract: The objective of this study is to assess the effect of geocomposite reinforcement on fatigue cracking, reflective cracking and permanent deformation accumulation of thin asphalt pavements. For this purpose, a full-scale trial section was constructed with different interfaces: unreinforced (reference) and reinforced with three types of geocomposites, formed by the combination of a bituminous membrane with a fabric or grid. The experimental program included accelerated pavement testing (APT) carried out by means of Fast Falling Weight Deflectometer (FastFWD) and laboratory tests (three point bending tests) on samples taken from the trial section. After APT, significant permanent deflections were observed, likely due to the plastic yielding of the unbound layers. Nevertheless, all the geocomposites improved the permanent deformation resistance as compared to the unreinforced pavement by reducing the vertical strain at the top of the subgrade. Moreover, the geocomposites increased the energy necessary for the crack propagation by three to eight times with respect to the unreinforced pavement. Overall, these findings indicate that the use of geocomposites can extend the service life of thin asphalt pavements in terms of both cracking and permanent deformation accumulation.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/276997

Sustainable Engineering for Resilient Built and Natural Environments
The First Outstanding 50 Years of “Università Politecnica delle Marche”
Autore/i: Alici, Antonello; Bocci, Maurizio; Bonvini, Paolo; Brocchini, Maurizio; Calamai, Alessandro; Canestrari, Francesco; Capozucca, Roberto; Carbonari, Alessandro; Carbonari, Sandro; Cardone, Fabrizio; Clementi, Francesco; Clini, Paolo; Cocchi, Giammichele; Corvaro, Sara; Darvini, Giovanna; Davì, Fabrizio; Dezi, Luigino; Di Giuseppe, Elisa; D’Orazio, Marco; Ferretti, Maddalena; Ferrotti, Gilda; Gara, Fabrizio; Giretti, Alberto; Graziani, Andrea; Lancioni, Giovanni; Lemma, Massimo; Lenci, Stefano; Lorenzoni, Carlo; Malinverni, Eva Savina; Mancinelli, Alessandro; Mariano, Fabio; Mentrasti, Lando; Mondaini, Gianluigi; Montecchiari, Piero; Munafò, Placido; Naticchia, Berardo; Postacchini, Matteo; Quagliarini, Enrico; Quattrini, Ramona; Ragni, Laura; Serpilli, Michele; Soldini, Luciano; Virgili, Amedeo; Zampini, Giovanni
Editore: Springer
Classificazione: 2 Contributo in Volume
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/272866

Research and Engineering for Resilient Infrastructures and Environment Protection
The First Outstanding 50 Years of “Università Politecnica delle Marche”
Autore/i: Bocci, Maurizio; Brocchini, Maurizio; Canestrari, Francesco; Cardone, Fabrizio; Corvaro, Sara; Darvini, Giovanna; Ferrotti, Gilda; Graziani, Andrea; Lorenzoni, Carlo; Mancinelli, Alessandro; Postacchini, Matteo; Soldini, Luciano; Virgili, Amedeo
Classificazione: 2 Contributo in Volume
Abstract: We discuss the contribution of the research groups that work at UNIVPM in the field of infrastructure engineering to the design of resilient hydraulic and transportation infrastructures and related solutions for the protection of the environment. After recalling the long history of research and engineering intervention of the groups of Hydraulics and Transportation Infrastructures of UNIVPM, we show how the activities of such groups are becoming of increasing importance in response to the growing request of innovative solutions for resilient infrastructures (e.g. coastal protection and maritime structures, road and airport pavements) and environment protection (e.g. coastal and river flood, air pollution, waste recycling and materials reuse). Such activities have been recently boosted by the resources made available to the two groups through the “Dipartimenti di Eccellenza” award, which largely focuses on the issue of engineering for resilient built and natural environments. A projection in the future of the activities of above is also proposed.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/273420

Influence of different fillers and SBS modified bituminous blends on fatigue, self-healing and thixotropic performance of mastics
ROAD MATERIALS AND PAVEMENT DESIGN
Autore/i: Mazzoni, G.; Virgili, A.; Canestrari, F.
Classificazione: 1 Contributo su Rivista
Abstract: The prediction of asphalt pavement performance is closely linked to the behaviour of mastic, consisting of filler and bitumen, which can be modelled as viscoelastic material. The purpose of this study is to investigate the effect of different fillers and bituminous blends on mastic fatigue response, considering recoverable phenomena in viscoelastic materials (thixotropy and self-healing) that concurrently occur. Three fillers (limestone, basalt and Portland cement) and three aged polymer modified bitumen contents (0%, 45% and 100%) were blended with a virgin polymer modified bitumen obtaining nine mastics characterised in terms of fatigue, self-healing and thixotropy using a Dynamic Shear Rheometer. Data obtained are analysed through a model previously adopted for polymer modified bitumens and mastics, allowing the determination of the fatigue endurance limit. Results show that the presence of filler with increasing particle density and/or Rigden voids causes a higher mastic stiffness without a clear trend on fatigue performance. In fact, great attention should be put on filler-bitumen interactions based on the physicochemical nature of filler. Moreover, whatever the filler considered, an enhancement in the fatigue endurance limit is detected in the mastics blended with a percentage of aged polymer modified bitumen (up to 45%), promoting the addition of Reclaimed Asphalt to obtain more performing and sustainable recycled mixtures.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/258328

Linear viscoelastic characterisation of bituminous mixtures using random stress excitations
ROAD MATERIALS AND PAVEMENT DESIGN
Autore/i: Graziani, A.; Cardone, F.; Virgili, A.; Canestrari, F.
Classificazione: 1 Contributo su Rivista
Abstract: The three-dimensional linear viscoelastic characterisation of bituminous mixtures can be performed with the concurrent measurement of the complex Young’s modulus and the complex Poisson’s ratio. This normally requires the application of sinusoidal excitations leading to small strain amplitudes. Since in the linear domain the effects of sinusoidal excitations are independent of each other, the material behaviour can also be obtained using a broad-band multi-frequency excitation. In this study, the complex Young’s modulus and Poisson’s ratio of a bituminous mixture was obtained by applying a random wave axial stress to cylindrical specimens and measuring their strain response in the axial and transverse direction. The frequency response functions representing the Young’s modulus and Poisson’s ratio were calculated using a conventional spectral analysis approach. Sinusoidal tests at different strain levels were also carried out as a reference. Applying random waves at 10, 20 and 30°C provided results with a high signal-to-noise ratio at frequencies between 0.1 Hz and 40 Hz for the Young’s modulus and between 1 and 90 Hz for Poisson’s ratio. For both functions the results validate the time-temperature superposition principle. The direct comparison with the results of sinusoidal testing confirms the accuracy of the frequency response functions measured with the random wave approach and shows their potential
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/267167

Testing the bond strength between cold bitumen emulsion composites and aggregate substrate
MATERIALS AND STRUCTURES
Autore/i: Graziani, Andrea; Virgili, Amedeo; Cardone, Fabrizio
Classificazione: 1 Contributo su Rivista
Abstract: Bitumen emulsion mixtures derive their mechanical properties from the cohesion provided by the bituminous mastic formed by bitumen and filler, and from its adhesion to the aggregate particles. In cold bitumen emulsion mixtures, the mastic film is produced upon emulsion breaking and the bond strength between mastic and aggregate must be evaluated considering the evolutive nature of the material, and thus the curing process. In this study, the binder bond strength (BBS) test was used to evaluate the bond strength between a bitumen emulsion, a cold mastic prepared using limestone filler and two aggregate substrates (limestone and basalt). A 2k factorial experiment was conducted also considering the influence of substrate moisture (dry and wet), curing time (24 and 72 h), curing temperature (25 and 40 °C) and moisture damage on the bond strength. The results demonstrated that, although both emulsion and mastic showed good affinity with the aggregate substrates, the adhesion bond between emulsion and basalt substrate was the most durable and that the use of a limestone filler penalised the moisture sensitivity of the systems. The BBS test was also able to show the positive effect of curing time and temperature on the bond strength.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/252906

Evaluation of bonding between reclaimed asphalt aggregate and bitumen emulsion composites
CONSTRUCTION AND BUILDING MATERIALS
Autore/i: Cardone, F.; Virgili, A.; Graziani, A.
Classificazione: 1 Contributo su Rivista
Abstract: The bond strength between bituminous binder and aggregate is fundamental to evaluate the performance and durability of cold bitumen emulsion mixtures (CBEM). The interaction developed at binder-aggregate interface is strongly dependent on the properties of aggregate, residual bitumen and emulsifiers, as well as on the environmental conditions affecting emulsion breaking. When reclaimed asphalt (RA) aggregate is used in the production of CBEM, the adhesion issue becomes more complex because the residual bitumen interacts with the aged bitumen film coating the RA aggregate surface. In this research, the binder bond strength (BBS) test was performed to evaluate the bonding between a bitumen emulsion, a cold mastic prepared using limestone filler and artificial RA substrates produced using two aggregate sources. The moisture sensitivity along with the effect of curing temperature and time on the bond strength development were also evaluated. The results showed good affinity between both cold bitumen emulsion composites and the aged bitumen film coating the RA substrate, also highlighting a reduced moisture sensitivity for most of the tested systems. Moreover, the BBS results allowed to properly discriminate the effect of curing temperature and time on bond strength between the artificial RA aggregate and the cold bitumen emulsion composites.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/259249

Estimation of low-temperature performance of recycled asphalt mixtures through relaxation modulus analysis
COLD REGIONS SCIENCE AND TECHNOLOGY
Autore/i: Stimilli, Arianna; Virgili, Amedeo; Canestrari, Francesco; Bahia, Hussain U.
Classificazione: 1 Contributo su Rivista
Abstract: In cold climates, pavements undergo extreme thermal conditions which cause premature cracking and failure. The inclusion of Reclaimed Asphalt Pavement (RAP) could worsen this tendency due to the reclaimed bitumen stiffening effects. However, nowadays strict economic and environmental sustainability requirements strongly encourage the use of high RAP content in asphalt mixes. In this context, this paper discusses the low temperature performance of mixtures designed with 40% RAP according to the Bailey method. Different bitumen contents and polymer modification levels were employed. A mixture with 25% of unfractioned RAP was employed as the reference mixture. Laboratory tests were performed through Asphalt Thermal Cracking Analyzer (ATCA) by applying thermal loadings on restrained and unrestrained asphalt beams. Based on experimental data the relaxation modulus was evaluated to rank the materials. Its accurate determination is fundamental for designing long lasting pavements with proper performance at low temperature. The analysis was performed through a new analytical methodology for obtaining the relaxation modulus master curve by measuring thermally induced stress and strain. The solution, based on Boltzmann's equation and pseudo-variables concepts, accounts for time and temperature dependency of bituminous materials, avoiding complex integral transformations. The proposed solution successfully integrates the current ATCA analysis providing reliable estimations of relaxation properties fundamental in modelling of pavement behavior. Mixtures containing 40% RAP demonstrated enhanced relaxation capabilities at low temperature showing significant improved behaviours than the reference mixture. Although high amount of reclaimed material, proper selection of RAP and type and quantity of virgin bitumen can improve low temperature performance.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/245769

Performance assessment of in plant produced warm recycled mixtures for open-graded wearing courses
TRANSPORTATION RESEARCH RECORD
Autore/i: Frigio, Francesca; Stimilli, Arianna; Virgili, Amedeo; Canestrari, Francesco
Classificazione: 1 Contributo su Rivista
Abstract: Sustainable solutions, such as the combination of reclaimed asphalt pavement (RAP) as a partial substitution of virgin materials and warm-mix asphalt (WMA) additives to decrease production temperatures, represent the new research frontier in the asphalt industry. Specific investigations must evaluate the consequences of recycled WMA performance, especially in the case of open-graded (OG) mixtures, given that lower production temperatures can affect the adhesion properties and durability of those materials. This paper describes an experimental effort that involved OG mixtures produced in plant at warm temperatures (130çC) with two WMA chemical additives characterized by different compositions. In addition, an equivalent mixture (used as a control for comparison purposes) was produced at standard temperatures. Each material was prepared with a polymer-modified binder and 15% RAP. The main objective of the study was to characterize volumetric and mechanical properties of the investigated mixtures with particular attention paid to compactability aptitude and durability. To this end, gyratory-compacted specimens were subjected to several laboratory tests after dry and wet conditioning (i.e., indirect tensile strength, Cantabro test, semicircular bending, and repeated indirect tensile loading). Moreover, plant production of the investigated mixtures made it possible to evaluate the feasibility of large-scale processes. The WMA mixtures showed significant water susceptibility, although they guaranteed good compactability and satisfied mechanical acceptance requirements and international recommendations for raveling resistance in dry conditions. The chemical composition of the WMA additives was found essential to reduce the water damage. Surfactants and adhesion enhancers included within one of the investigated WMA additives ensured better water resistance than the other additive classified as a viscous regulator.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/245782

Mix design validation through performance-related analysis of in plant asphalt mixtures containing high RAP content
INTERNATIONAL JOURNAL OF PAVEMENT RESEARCH AND TECHNOLOGY
Autore/i: Stimilli, Arianna; Virgili, Amedeo; Giuliani, Felice; Canestrari, Francesco
Classificazione: 1 Contributo su Rivista
Abstract: Producing new asphalt mixtures with high content of Reclaimed Asphalt Pavement (RAP) is a major challenge in road construction for economic and environmental reasons. Although many laboratory studies addressed this issue, concerns related to the number of variables involved in the plant production process still limit hot recycling, especially when Styrene–Butadiene–Styrene (SBS) modified bitumens are used. In this sense, plant produced mixtures should be directly investigated to obtain reliable performance evaluations. Given this background, the paper proposes the mechanical characterization of dense-graded mixtures with 40% RAP produced at the asphalt plant as part of rehabilitation activities of an in-service motorway. The Bailey Method was applied to optimize the mix design. Mixtures were prepared by using two polymer modified bitumens (with high and low SBS polymer content) and selected RAP fractions composed only of asphalt layers including SBS modified bitumen itself. An additional mixture prepared according to the current practice for binder layers of motorway pavements was produced for comparison purposes. Advanced laboratory tests allowed the determination of the main material properties (i.e. compactability, cracking and rutting aptitude, indirect tensile strength, fatigue and self-healing). Results showed that mixtures with 40% RAP had performance comparable or even enhanced than the reference mixture especially when prepared with low modified bitumens. Consequently, this study shows that an accurate mix design and the selection of adequate bitumens overcome the potential drawbacks related to the use of high RAP percentage given the possibility to produce suitable recycled mixtures.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/245770

Warm recycling of flexible pavements: Effectiveness of Warm Mix Asphalt additives on modified bitumen and mixture performance
JOURNAL OF CLEANER PRODUCTION
Autore/i: Stimilli, Arianna; Virgili, Amedeo; Canestrari, Francesco
Classificazione: 1 Contributo su Rivista
Abstract: In pavement industry, environmental and economical sustainability stimulates technical solutions able to drastically decrease pollutants and energy costs caused by high production temperatures. In this sense, recent research efforts focused on innovative technologies able to significantly reduce mixing and compaction temperature. The so called Warm Mix Asphalts (WMA) are bituminous mixtures produced at reduced temperatures through specific additives based on different mechanisms. The novelty of WMA technologies determines a lack of experience about their effectiveness, which requires dedicated research activities, especially when polymer modified bitumens and Reclaimed Asphalt Pavement (RAP) are used. Given this context, the present study proposes a comprehensive laboratory investigation on dense-graded mixtures produced through different WMA additives representative of the main categories currently available on the market (i.e. chemical, organic and water-based). Mixtures were prepared including Styrene-Butadiene-Styrene polymer modified bitumen and 25% of RAP to evaluate potential benefits deriving from the combination of warm and recycling techniques. For a complete understanding of WMA additive effects, mechanical tests (i.e. compactability, stiffness, fatigue) carried out on mixtures in a broad range of loading configurations were integrated by rheological analyses on bitumens. Results indicate that lower production temperatures allowed a significant decrease in stiffness, effectively balancing the inclusion of RAP material without penalizing mixture performance. Compactability, volumetric and fracture properties indicate the possibility to produce suitable recycled warm mixtures when the appropriate WMA additive is selected. The chemical additive appeared able to provide overall improved performance, whereas the organic additive made the mixture brittle and susceptible to permanent cracking.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/250298

Characterization of the three-dimensional linear viscoelastic behavior of asphalt concrete mixtures
CONSTRUCTION AND BUILDING MATERIALS
Autore/i: Graziani, Andrea; Cardone, Fabrizio; Virgili, Amedeo
Classificazione: 1 Contributo su Rivista
Abstract: Mechanistic-empirical pavement design methods typically require the identification of the complex Young’s modulus and Poisson’s ratio for the characterization of bituminous layers. However, since in small deformation the frequency-dependent shear and bulk responses of an isotropic body are decoupled, the complex shear and bulk moduli are generally considered fundamental response functions. The objective of this study was to perform the experimental characterization of the three-dimensional response of asphalt mixtures in the linear viscoelastic domain, through the simultaneous measurement of the complex moduli E⁄, K⁄ and G⁄ and the complex Poisson’s ratio m⁄. The testing program consisted of cyclic compression and cyclic tension–compression uniaxial tests on cylindrical specimen, with the measurement of both axial and transverse strain. In particular, frequency sweeps were carried out at temperatures between 0, and 40 C and at axial strain levels between 15 and 60 le. Experimental results highlighted that, for the tested mixture, the time–temperature superposition principle was applicable to both the bulk and shear response, and consequently to the axial response. E⁄ and G⁄ showed very similar trends in terms of both stiffness moduli and loss angle, whereas K⁄ values highlighted smaller frequency dependence. The time–temperature superposition principle was also applicable to m⁄ whose master curves can be qualitatively described using the local approximation to the Kramers–Kronig relations. Results suggest that the simultaneous assessment of bulk and shear response may be a useful tool for the performance characterization of asphalt mixtures.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/229800

In plant production of hot recycled mixtures with high reclaimed asphalt pavement content: A performance evaluation
8th RILEM International Symposium on Testing and Characterization of Sustainable and Innovative Bituminous Materials
Autore/i: Stimilli, Arianna; Virgili, Amedeo; Giuliani, Felice; Canestrari, Francesco
Editore: Kluwer Academic Publishers
Classificazione: 4 Contributo in Atti di Convegno (Proceeding)
Abstract: Nevertheless hot recycling process is nowadays a widespread technique, many doubts related to the in plant recycling process effects on the performance of recycled mixtures still exist and limit the maximum allowable amount of Reclaimed Asphalt Pavement (RAP). Therefore, the feasibility of an efficient production of plant hot recycled mixtures characterized by high RAP content and suitable performance should be properly addressed. To this aim, the overall performance of hot recycled asphalt mixtures produced in asphalt plant and containing high RAP content were assessed in this study. The mixtures were prepared with two different bitumens (high and low content of SBS polymer modifier) and 40 % of RAP only deriving from asphalt layers containing polymer modified bitumens. The aggregate grading curve was previously optimized through a specific laboratory study by applying the Bailey Method and using selected RAP. A third mixture, currently used for binder layers in motorway pavements, was also studied for comparative purposes. Compactability, stiffness, cracking and rutting resistance and fatigue behavior were investigated. Results of the mechanical tests suggest that mixtures containing 40 % RAP are suitable for the production of new asphalt pavements, especially when low modified bitumens are used. In fact, the performance of such mixtures were comparable or even higher than those of the reference mixture. In particular, the specific and accurate mix design allowed the potential drawbacks due to higher RAP content to be balanced.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/232974

Modern electronic devices: An increasingly common cause of skin disorders in consumers
DERMATITIS
Autore/i: Corazza, M.; Minghetti, S.; Bertoldi, A. M.; Martina, E.; Virgili, A.; Borghi, A.
Classificazione: 1 Contributo su Rivista
Abstract: The modern conveniences and enjoyment brought about by electronic devices bring with them some health concerns. In particular, personal electronic devices are responsible for rising cases of several skin disorders, including pressure, friction, contact dermatitis, and other physical dermatitis. The universal use of such devices, either for work or recreational purposes, will probably increase the occurrence of polymorphous skin manifestations over time. It is important for clinicians to consider electronics as potential sources of dermatological ailments, for proper patient management. We performed a literature review on skin disorders associated with the personal use of modern technology, including personal computers and laptops, personal computer accessories, mobile phones, tablets, video games, and consoles.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/301421

Modeling and assessment of self-healing and thixotropy properties for SBS modified binders
INTERNATIONAL JOURNAL OF FATIGUE
Autore/i: Canestrari, Francesco; Virgili, Amedeo; Graziani, Andrea; Stimilli, Arianna
Classificazione: 1 Contributo su Rivista
Abstract: The fatigue endurance limit of binders is the results of more phenomena (e.g. viscoelasticity, damage, healing, thixotropy, steric hardening) that interact simultaneously making the mechanisms behind the fatigue behavior not properly understood. Currently, there is no consolidated analytical approach inclusive of such phenomena to characterize fatigue performance. This research proposes a criterion to determine the fatigue resistance of binders subjected to monotonous cyclic loading with multiple rest periods. The main rheological properties are measured during each stage using a Dynamic Shear Rheometer and the modeling of their evolution is proposed. The experimental program includes different binders in order to investigate the effects of SBS modification levels and aged binder contents on self-healing potential and fatigue behavior. The proposed criterion enables to identify fundamental contributions leading to a comprehensive fatigue endurance limit. This approach allows different binders to be distinguished taking into account their self-healing capacity and can help to establish a better correlation with in-service performance of mixtures. Moreover, a comparison with a previous analytical approach based on the same kind of test (time sweep) with only one rest period is proposed in order to evaluate the effectiveness and reliability of the proposed criterion. Results show that multiple rest periods are needed in order to fully understand the self-healing and fatigue behavior of bituminous binders and to quantify the contributions given by thixotropy. © 2014 Elsevier Ltd. All rights reserved.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/224126

New method to estimate the “re-activated” binder amount in recycled hot-mix asphalt
ROAD MATERIALS AND PAVEMENT DESIGN
Autore/i: Stimilli, Arianna; Virgili, Amedeo; Canestrari, Francesco
Classificazione: 1 Contributo su Rivista
Abstract: The magnitude of the binder re-activation within the reclaimed asphalt pavement (RAP) fraction is a major concern when recycled hot-mix asphalt (HMA) is produced, since it directly affects the final performance of the mix. Currently, no reliable methods to predict the RAP binder re-activation are available and the lack of such information prevents the quantification of the proper amount of virgin binder to be added to the recycled HMA.This study proposes a new method to estimate the re-activated binder amount based on the surface area (SA) of RAP aggregates. Laboratory results demonstrated the effectiveness of the SA approach in the case of RAP amounts typically used for hot-recycled HMA. Moreover, the experimental investigation suggested that revised coefficients are needed for the evaluation of the SA to account for the presence of clumps when high amounts of fine RAP aggregates are used.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/232925

Pseudo-variables method to calculate HMA relaxation modulus through low-temperature induced stress and strain
MATERIALS & DESIGN
Autore/i: Canestrari, Francesco; Stimilli, Arianna; Bahia, Hussain U.; Virgili, Amedeo
Classificazione: 1 Contributo su Rivista
Abstract: Thermal cracking is a critical failure mode for asphalt pavements. Relaxation modulus is the major viscoelastic property that controls the development of thermally induced tensile stresses. Therefore, accurate determination of the relaxation modulus is fundamental for designing long lasting pavements. This paper proposes a reliable analytical solution for constructing the relaxation modulus master curve by measuring stress and strain thermally induced in asphalt mixtures. The solution, based on Boltzmann's Superposition Principle and pseudo-variables concepts, accounts for time and temperature dependency of bituminous materials modulus, avoiding complex integral transformations. The applicability of the solution is demonstrated by testing a reference mixture using the Asphalt Thermal Cracking Analyzer (ATCA) device. By applying thermal loadings on restrained and unrestrained asphalt beams, ATCA allows the determination of several parameters, but is still unable to provide reliable estimations of relaxation properties. Without them the measurements from ATCA cannot be used in modeling of pavement behavior. Thus, the proposed solution successfully integrates ATCA experimental data. The same methodology can be applied to all test methods that concurrently measure stress and strain. The statistical parameters used to evaluate the goodness of fit show optimum correlation between theoretical and experimental results, demonstrating the accuracy of this mathematical approach.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/225311

Structural response of grid-reinforced bituminous pavements
MATERIALS AND STRUCTURES
Autore/i: Graziani, Andrea; Emiliano, Pasquini; Ferrotti, Gilda; Virgili, Amedeo; Canestrari, Francesco
Classificazione: 1 Contributo su Rivista
Abstract: Grid reinforcement is becoming a standard construction and rehabilitation technique to improve the performance of bituminous pavements. Currently, selection of the appropriate grid type and position is based on empirical criteria or derived from the results of laboratory tests which consider a single aspect of the mechanical behavior of the grid-reinforced systems. An improvement in the existing design and testing approaches could be obtained considering the actual response of grid-reinforced systems under vehicular loads. An instrumented pavement section was constructed to achieve this objective by installing a glass fiber polymer grid (FP) and a carbon fiber/glass fiber grid (CF) inside a double-layered asphalt surfacing along an in-service road. This pavement is part of a wider project which also involves a RILEM inter-laboratory test on the same reinforced systems. The pavement response to falling weight deflectometer (FWD) and real-scale truck loads was measured using pressure cells and asphalt strain gauges installed inside the pavement. A layered elastic theory (LET) model was adopted to perform both back-calculation of layer moduli and forward-calculation (simulation) of pavement stress and strain. The FWD and the real-scale tests yielded congruent results highlighting that the strain field inside the double-layered surfacing was considerably reduced by the installation of the CF/glass fiber grid whereas the glass FP grid was probably too stiff, potentially leading to interface debonding. The LET model proved to be a simple and effective tool for a first-approach analysis of the reinforcement pavement response.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/150303

Original Approach to Predict Fatigue Endurance Limit of Asphalt Binders Considering Healing Capacity
Rheology and processing of construction materials
Autore/i: Canestrari, Francesco; Graziani, Andrea; Virgili, Amedeo; Stimilli, Arianna
Editore: Nicolas Roussel and Hela Bessaies-Bey
Classificazione: 4 Contributo in Atti di Convegno (Proceeding)
Abstract: More phenomena interact (e.g. viscoelasticity, damage, healing) contributing to the overall behavior of binders in terms of fatigue endurance limit. However, currently there is no consolidated analytical approach inclusive of strength recovery during rest periods to characterize fatigue performance. This research proposes a criterion to determine the resistance of binders subjected to monotonous cyclic loading with multiple rest times by using a Dynamic Shear Rheometer. Main rheological properties are measured and the modeling of their evolution during each stage is proposed. The experimental program includes different binders in order to investigate the effects of SBS modification levels and aged binder contents on healing potential. Beyond the classical component related to damage analysis, the proposed criterion enables to identify other fundamental contributions, leading to a comprehensive fatigue endurance limit. This approach allows distinguishing binders taking into account their healing capacity and should provide a better correlation with in-service performance of mixtures.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/115070

An experimental approach to the rheological characterization of bituminous mixture based on pseudo-random stress excitations
Rheology and Processing of Construction Materials
Autore/i: Virgili, Amedeo; Canestrari, Francesco; Graziani, Andrea
Editore: Nicolas Roussel and Hela Bessaies-Bey
Classificazione: 4 Contributo in Atti di Convegno (Proceeding)
Abstract: Rheological behavior of bituminous mixtures in the small strain domain is effectively described by the Linear Visco-­‐Elasticity (LVE) theory. Since the response of LVE materials is equivalent to that of Linear Time-­‐Invariant (LTI) systems, material functions that are used to characterize LVE behavior in the frequency domain can be considered as Frequency Response Functions (FRF) of a LTI system. In this experimental research a pseudo-­‐random stress excitation, comprising a broad band of harmonic components, is used to estimate the LVE response function of a bituminous mixture using signals and systems oriented techniques. Cylindrical specimens were tested in tension-compressions configuration, both excitation (stress) and response (strain) signals were analyzed using a spectral analysis. The FRF estimated using pseudo-­random experiments is compared with conventional harmonic analysis results. Advantages and limitations of the proposed approach are highlighted, paying particular attention to the possible effects of non-­‐linearity and viscoplastic deformations.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/115071

Experimental Study on Shear Fatigue Behavior and Stiffness Performance of Warm Mix Asphalt by adding Synthetic Wax
CONSTRUCTION AND BUILDING MATERIALS
Autore/i: Petit, C.; Millien, A.; Canestrari, Francesco; Pannunzio, V.; Virgili, Amedeo
Classificazione: 1 Contributo su Rivista
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/71053

Characterisation of permanent deformation behaviour of unbound granular materials under repeated triaxial loading
CONSTRUCTION AND BUILDING MATERIALS
Autore/i: Cerni, G.; Cardone, Fabrizio; Virgili, Amedeo; Camilli, S.
Classificazione: 1 Contributo su Rivista
Abstract: The present paper reports the results of a laboratory experiment that aimed to investigate the permanent deformation behaviour of two unbound granular materials for road subbase layers under repeated triaxial loading. In the first part of research the shakedown concept was used to classify the mechanical response of the granular mixtures. The obtained results confirmed the potential usefulness of this theoretical approach for ranking granular materials with regard to their rutting potential. The second part was entirely dedicated to the development of an analytical model to describe the long-term permanent deformation behaviour of these materials. The proposed model allowed permanent strain accumulation as function of the number of load applications and applied stress level to be described. The results, besides being consistent with the shakedown concept, showed the ability of the model to reflect the change in mechanical behaviour due to the different nature of materials, under specific stress and moisture condition. In addition, the model allowed the permanent deformation accumulation resistance of the material to be properly investigated through specific strain rate envelope curves defined on a Mohr–Coulomb diagram. Therefore, this study could propose an innovative and practical design approach for permanent deformation behaviour assessment of unbound granular material and consequently for evaluating its suitability in the pavement in order to avoid undesirable response.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/66287

Experimental evaluation of the influence of surface coating on fiberglass geogrid performance in asphalt pavements
GEOTEXTILES AND GEOMEMBRANES
Autore/i: Ferrotti, Gilda; Canestrari, Francesco; Pasquini, Emiliano; Virgili, Amedeo
Classificazione: 1 Contributo su Rivista
Abstract: In road infrastructures, the maintenance of existing pavements is one of the most important issues to deal with. In order to optimize rehabilitation costs and increase pavement service life, innovative technical solutions have been developed. One of the most widespread techniques introduced for this scope, consists in the application of geogrids at the interface between different layers of pavement structures. Geogrids provide different performance depending on their characteristics, such as constituent materials, surface coating, mesh geometry and dimensions, and on their position in the pavement structure. In fact, these materials can be placed between different layers (bounded and/or unbounded) carrying out different functions. In this survey, the reinforcement of asphalt concrete layers was studied in laboratory, paying particular attention to the effects that different surface coatings, consisting in different treatments of the surface of the mesh elements of the geogrid, produce on the performance of fiberglass reinforced asphalt concrete specimens. The experimental analysis was carried out in two different stages. During the first stage, the coatings themselves were investigated, studying their adhesion properties with a conventional asphalt binder, in order to check their capability to adhere to the constitutive material of an asphalt concrete. During the second stage, a specific testing protocol was followed in order to investigate the performance of double-layered asphalt concrete specimens by means of interlayer shear tests and four-point bending tests. The results showed that the testing protocol used is suitable for studying, in laboratory, the performance of reinforced pavements, that could be influenced, both in terms of interlayer bonding between asphalt concrete layers and four-point bending test characteristics, by the application of a coating on the surface of the geogrids.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/71051

Clear Asphalt Mixture for Wearing Course in Tunnels: Experimental Application in the Province of Bolzano
PROCEDIA: SOCIAL & BEHAVIORAL SCIENCES
Autore/i: Bocci, Maurizio; Grilli, A.; Cardone, Fabrizio; Virgili, Amedeo
Classificazione: 1 Contributo su Rivista
Abstract: A new technical and political awareness on safety driving and reduction of environmental impact have increased the use of coloured asphalt pavements in road construction. A clear asphalt mixture (CAM) for wearing courses, designed and laid down during the rehabilitation of an Italian tunnel, was subjected to the acceptance inspection, mechanical characterization and determination of photometric properties. Traditional and performance-based tests were carried out to determine the failure resistance, compactability, stiffness, abrasion resistance and water sensitivity of the CAM. Luminance and reflection properties of CAM were measured and compared with those of HMA in order to assess possible lighting benefits.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/82372

INSTRUMENTED TEST SECTION FOR THE EVALUATION OF GEOGRIDS IN ASPHALT PAVEMENTS
CONFERENCE PROCEEDINGS 5th INTERNATIONAL CONFERENCE BITUMINOUS MIXTURES AND PAVEMENTS
Autore/i: Graziani, Andrea; Virgili, Amedeo; Belogi, Leonello
Classificazione: 4 Contributo in Atti di Convegno (Proceeding)
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/56208

A strategic laboratory approach for the performance investigation of geogrids in flexible pavements
CONSTRUCTION AND BUILDING MATERIALS
Autore/i: Ferrotti, Gilda; Canestrari, Francesco; Virgili, Amedeo; Grilli, A.
Classificazione: 1 Contributo su Rivista
Abstract: ABSTRACT: Nowadays, the increasing request in terms of road transport makes maintenance and rehabilitation of road infrastructures key tasks for road engineering. In recent years, numerous products/materials have been introduced on the market and can be used in combination or singly in order to extend pavement life and guarantee high performance. Among them, geosynthetics can play different roles in pavement structures, such as draining, reinforcement, filtering, separation, protection, and proofing. This research focuses on the validation of a strategic laboratory approach for the study of the mechanical performance of reinforced systems used in flexible pavements, combining repeated loading cycles in a four-point bending configuration with interlayer shear tests. This method can be used in further research analysis to compare unreinforced and reinforced double-layered systems. The results obtained in this investigation showed that the fiberglass grid used provides a relevant contribution to the performance of the asphalt concrete system studied.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/71045

Analysis of Water and Thermal Sensitivity of Open Graded Asphalt Rubber Mixtures
CONSTRUCTION AND BUILDING MATERIALS
Autore/i: Partl, M. N.; Pasquini, Emiliano; Canestrari, Francesco; Virgili, Amedeo
Classificazione: 1 Contributo su Rivista
Abstract: This research investigates the water and thermal sensitivity of two open graded mixtures prepared with asphalt rubber binder, one mixture containing lightweight aggregates (expanded clay) replacing a part of coarse fraction. Fatigue tests using the CoAxial Shear Test (CAST) apparatus were performed in both dry and wet conditions with and without temperature cycles. Results showed that fatigue resistance of the studied materials was only little affected by water and temperature cycles and superior to traditional open graded mixtures produced with SBS modified bitumen only. The results were also validated and modelled by means of an elasticity-based damage model.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/30483

An Evaluation of Use of Synthetic Waxes in Warm Mix Asphalt
Advanced Testing and Characterization of Bituminous Materials
Autore/i: Cardone, Fabrizio; Pannunzio, V; Virgili, Amedeo; Barbati, S.
Editore: CRC PRESS - Taylor & Francis Group
Classificazione: 4 Contributo in Atti di Convegno (Proceeding)
Abstract: The preservation and protection of both natural and workspace environment are two of the main objectives that also concern the field of road engineering. As such, there is an ever increasing use of new pro-environmental techniques and materials. One of these innovative processes includes warm mix asphalt (WMA). Such asphalt mixtures, compared with traditional hot mix asphalt (HMA), need lower mixing and compaction temperatures, allowing lower CO2 and fume emission, reducing energy consumption and operative benefits. In this context the present experimental study was conducted to evaluate the workability and mechanical performance of WMA by adding synthetic waxes. Three different asphalt mixtures were selected, the first was a traditional mix, as reference material, while the other were two mixes modified with synthetic long carbon chain wax. The experimental investigation consisted of a compaction grade study by different laboratory compaction techniques and of dynamic tests to evaluate the mechanical response of WMA compared to HMA.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/53756

Repeated load test on bituminous systems reinforced by geosynthetics
GEOTEXTILES AND GEOMEMBRANES
Autore/i: Virgili, Amedeo; Canestrari, Francesco; Grilli, Andrea; Santagata, Felice Ausilio
Classificazione: 1 Contributo su Rivista
Abstract: This paper focuses on a better understanding of the influence of geosynthetic reinforcement materials on the flexural behaviour of bi-layer bituminous systems, and evaluates the effects of these materials on bituminous system resistance to repeated loading cycles. In this research project, three different bi-layer reinforced systems were investigated and compared with a non-treated bi-layer system and a bi-layer system with tack coat. In particular, three different geosynthetics were used: a Glass fiber Geogrid, a Polyester Geogrid and a Geomembrane. All bi-layer bituminous systems were tested by means of a four-point bending test under repeated loading cycles. The failure criterion was defined as the number of loading cycles corresponding to the flex point of the permanent deformation evolution, i.e., where the permanent deformation evolution inverts its trend (from decreasing to increasing rate). In order to precisely determine the number of loading cycles corresponding to the flex point of a permanent deformation evolution curve, a descriptive model, based on a classic power law, is presented. The proposed model precisely simulates the mechanical behaviour of bituminous mixtures and allows a reliable comparison amongst the different bituminous systems tested.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/51378

Damage model for environmental conditioned fatigue test with CAST
FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES
Autore/i: Virgili, Amedeo; M. N., Partl; A., Grilli; Santagata, Felice Ausilio
Editore: editori indicati: Kluwer Academic Publishers, Sijthoff, Noordhoff , Nijhoff Luoghi Dordrecht, The Hague
Classificazione: 1 Contributo su Rivista
Abstract: The aim of this paper is to suggest a unified test method that allows investigation into the different effects and contribution of water damage and temperature cycles on fatigue performance of asphalt mixtures by means of a CoAxial Shear Test (CAST). A continuum damage approach, based on the elasticity theory, is chosen to determine the damage level of each tested specimen. The proposed mathematical model allows the simulation of the modulus evolution in the fatigue test and takes into account the temperature cycles. In this way, a unique scalar damage factor determines the damage process severity in each specimen and allows a rational comparison between each different condition.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/25595

Correlation between binder and bituminous mixture fatigue behaviour
Proceedings of the 4° International Congress SIIV “Advances in Transport Infrastructures and Stakeholders Expectations”
Autore/i: Cardone, Fabrizio; Cerni, G; Colagrande, S; Virgili, Amedeo
Classificazione: 4 Contributo in Atti di Convegno (Proceeding)
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/52587

Experimental analysis of the potentialities and limits of asphalt mixtures by adding zeolite
4° International SIIV congress
Autore/i: Bocci, Maurizio; Virgili, Amedeo; A., Grilli; V., Pannunzio
Classificazione: 4 Contributo in Atti di Convegno (Proceeding)
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/53220

Influence of reinforcement geosynthetics on flexion behaviour of double-layer bituminous systems
Proceedings, International Conference: Advanced Characterization of Pavement and Soil Engineering Materials
Autore/i: Bocci, Maurizio; A., Grilli; Santagata, Felice Ausilio; Virgili, Amedeo
Classificazione: 4 Contributo in Atti di Convegno (Proceeding)
Abstract: ABSTRACT: High performance materials, like geosynthetics, have to be analysed in order to determine whether these products act as reinforcement and enable longer pavement durability. A new research project on fatigue investigations of reinforced asphalt pavement is in progress at the Università Politecnica delle Marche (Italy) and the results presented in this paper are part of the overall experimental program. In particular, the purpose of the present work is to compare three reinforcement systems and to understand the corresponding fatigue behaviour under controlled deflection and controlled load modes. To this end, double layered prismatic specimens have been used to perform four point bending fatigue tests. Test results have been elaborated considering the following approaches: − dissipated energy for controlled deflection mode; − number of cycles of applied load to failure for controlled load mode. Both test methods have shown improved fatigue life for reinforced systems compared with the unreinforced one.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/53487

Interlayer Shear Effects of Grid Reinforcements
10th INTERNATINAL CONFERENCE ON ASPHALT PAVEMENTS
Autore/i: Canestrari, Francesco; A., Grilli; F. A., Santagata; Virgili, Amedeo
Editore: International Society for Asphalt Pavements
Classificazione: 4 Contributo in Atti di Convegno (Proceeding)
Abstract: It is well known that cracking in asphalt pavements and its related degradation processes can be caused by traffic loading and temperature variations. Moreover, the increasing traffic, higher axle loads and reduced road maintenance budget, force engineers to seek alternative materials and/or working methods for the design and rehabilitation of asphalt pavements. In this context there is an increasing interest in the use of reinforcement systems to provide higher durability of asphalt pavements. In fact, they could extend service life preventing pavement cracking with a reduction in maintenance costs. In order to improve our knowledge of pavement reinforcement applications, the present study focuses on the analysis of bonding at the interface between asphalt concrete layers and reinforcements. In fact, geosynthetics could not act as a reinforcement product if they are a cause of separation between the layers at the interface. The aim of this study concerns a better understanding of reinforcement systems behaviour and their effects on mechanical properties of the interface. To this purpose the interlayer direct shear test ASTRA (Ancona Shear Testing Research and Analysis) is used to provide more details regarding the comprehension of the interlayer shear resistance. In particular, this paper presents the results obtained using four types of reinforcements at the interface, with both conventional and porous wearing course for the upper layer of laboratory samples. Our experimental program considers the effects of various test parameters, among which temperature and normal stress, in order to investigate the influence of the reinforcement properties (stiffness, geometry, size, coating, etc.) on the interlayer shear strength and stiffness.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/52326

Proposta di catalogo di pavimentazioni stradali in cubetti di pietra in ambito urbano
Atti del 16° Convegno Nazionale SIIV “Manutenzione ed adeguamento delle strade esistenti”
Autore/i: G., Cerni; S., Colagrande; Cardone, Fabrizio; Virgili, Amedeo
Classificazione: 4 Contributo in Atti di Convegno (Proceeding)
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/52061

THE USE OF FOAMED BITUMEN IN THE COLD RECYCLING OF ROAD PAVEMENTS
5TH INTERNATIONAL CONGRESS VALORISATION AND RECYCLING OF INDUSTRIAL WASTE
Autore/i: Bocci, Maurizio; Cerni, G.; Colagrande, S.; Virgili, Amedeo
Classificazione: 4 Contributo in Atti di Convegno (Proceeding)
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/44611

Performance analysis of mixtures produced using foamed bitumen
3rd SIIV International Conference
Autore/i: Bocci, Maurizio; Cardone, Fabrizio; G., Cerni; Virgili, Amedeo
Classificazione: 4 Contributo in Atti di Convegno (Proceeding)
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/53815

The Use of Residual Muds Obtained by the Production of Tiles in Road Embankments
Atti del 4° International Congress VARIREI “Valorization and recycling of industrial waste”
Autore/i: Cardone, Fabrizio; G., Cerni; S., Colagrande; Virgili, Amedeo
Classificazione: 4 Contributo in Atti di Convegno (Proceeding)
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/47964

L’impiego del Bitume Schiumato nel Riciclaggio a Freddo delle Pavimentazioni Stradali
VARIREI 2005 V° International Congress on Valorisation and Recycling of Industrial Waste, L'Aquila (Italy)
Autore/i: Bocci, Maurizio; G., Cerni; S., Colagrande; Virgili, Amedeo
Classificazione: 4 Contributo in Atti di Convegno (Proceeding)
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/44240

Caratterizzazione dei bitumi stradali alle basse temperature con il Direct Tension Device
STRADE & AUTOSTRADE
Autore/i: Canestrari, Francesco; Cardone, Fabrizio; E., Santagata; F. A., Santagata; Virgili, Amedeo
Classificazione: 1 Contributo su Rivista
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/51346

La tecnica della simulazione statistica applicata allo studio teorico ed alla progettazione delle intersezioni stradali
Autore/i: Virgili, Amedeo; G., Cerni; Cardone, Fabrizio; Graziani, Andrea
Classificazione: 5 Altro
Abstract: Atti del CIRS, Centro Sperimentale Interuniversitario di Ricerca Stradale, Gennaio 2003.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/71099

Applicazione di un modello di simulazione alla progettazione della corsia di accelerazione
Atti del CIRS, Centro Sperimentale Interuniversitario di Ricerca Stradale
Autore/i: Baglieri, O; Graziani, Andrea; Toraldo, E; Virgili, Amedeo
Classificazione: 5 Altro
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/49512

Formulazione generale dei raccordi plano-altimetrici definiti sulla base del comportamento dell’utente
Atti del XII Convegno Internazionale SIIV
Autore/i: Canestrari, Francesco; Graziani, Andrea; Virgili, Amedeo
Classificazione: 4 Contributo in Atti di Convegno (Proceeding)
Abstract: SIIV - XII Convegno Internazionale: Riqualificazione funzionale e sicurezza del sistema viario. Universita' degli studi di Parma
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/53399

A study on the mechanical characteristics of cold recycled bituminous concretes
4th European Symposium on "Performance of Bituminous and Hydraulic Materials in Pavements", Nottingham (U.K.), April 11÷12, 2002
Autore/i: Bocci, Maurizio; Virgili, Amedeo; S., Colagrande
Classificazione: 4 Contributo in Atti di Convegno (Proceeding)
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/70905

INDAGINE SULLE CARATTERISTICHE MECCANICHE DEI CONGLOMERATI BITUMINOSI RICICLATI A FREDDO
BITMAT IV SIMPOSIO EUROPEO - NOTTINGHAM
Autore/i: Bocci, Maurizio; Virgili, Amedeo; Colagrande, S.
Classificazione: 4 Contributo in Atti di Convegno (Proceeding)
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/43750

Indagine sull'influenza delle proprietà reologiche del legante sul comportamento meccanico del conglomerato bituminoso
XI Convegno Nazionale SIIV, Verona 28÷30 Novembre 2001
Autore/i: Cerni, G.; Virgili, Amedeo
Classificazione: 4 Contributo in Atti di Convegno (Proceeding)
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/40448

Realizzazione di una apparecchiatura monoassiale per prove di fatica e di creep dinamico sui conglomerati bituminosi: descrizione del software di controllo
Autore/i: Virgili, Amedeo
Classificazione: 5 Altro
Abstract: Atti del CIRS, Centro Sperimentale Interuniversitario di Ricerca Stradale, Gennaio 2001
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/70909

Determinazione reologica della suscettività all'acqua delle terre fini
XI Convegno Nazionale SIIV, Verona 28÷30 Novembre 2001
Autore/i: G., Cerni; Virgili, Amedeo
Classificazione: 4 Contributo in Atti di Convegno (Proceeding)
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/70908

Influenza dell’attivante d’adesione sul comportamento reologico del conglomerato bituminoso
X Convegno Nazionale SIIV
Autore/i: Bocci, Maurizio; Cerni, G.; Fiorentino, M.; Virgili, Amedeo
Classificazione: 4 Contributo in Atti di Convegno (Proceeding)
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/40450

Realizzazione di una apparecchiatura monoassiale per prove di fatica e di creep dinamico sui conglomerati bituminosi: descrizione del prototipo
Autore/i: Virgili, Amedeo
Classificazione: 5 Altro
Abstract: Atti del CIRS, Centro Sperimentale Interuniversitario di Ricerca Stradale, Gennaio 2000
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/70910

Bozza di nuova normativa CNR sulla determinazione della deformabilità a carico costante di miscele bituminose e calcolo del modulo complesso
Autore/i: F. A., Santagata; Virgili, Amedeo
Classificazione: 5 Altro
Abstract: Atti del CIRS, Centro Sperimentale Interuniversitario di Ricerca Stradale, Gennaio 1999
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/70911

Analisi dei risultati di uno studio multicentrico italiano su efficacia e tollerabilità di fluconazolo 100/mg die nel trattamento delle micosi cutanee.
GIORNALE ITALIANO DI DERMATOLOGIA E VENEREOLOGIA
Autore/i: Bossi, Guido; Cecchini, F; Bonci, Andrea; LICASTRO CICERO, R; Cainelli, T; Rozzoni, M; Cervetti, O; Forte, M; MARCHI R, De; Bossi, Guido; Offidani, Annamaria; Cellini, A; Simonetti, Oriana; Rebora, A; Guarrera, M; RON GIOLETTI, F; Santoianni, P; Scalvenzi, M; Califano, A; Virgili, Amedeo
Classificazione: 1 Contributo su Rivista
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/34597

Alcune relazioni tra grandezze volumetriche e meccaniche di conglomerati bituminosi
XXIII Convegno Nazionale Stradale
Autore/i: Bocci, Maurizio; Cerni, G.; Virgili, Amedeo
Classificazione: 4 Contributo in Atti di Convegno (Proceeding)
Abstract: Verona
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/40452

Considerazioni sulla corretta valutazione del modulo complesso dei conglomerati bituminosi mediante prove di creep dinamico
VII Convegno Nazionale SIIV, Pisa 29÷30 Ottobre 1997
Autore/i: Virgili, Amedeo; F. A., Santagata
Classificazione: 4 Contributo in Atti di Convegno (Proceeding)
Abstract: VII Convegno Nazionale SIIV, Pisa 29÷30 Ottobre 1997
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/70912

Proposta di revisione della normativa CNR sulla determinazione della deformabilità a carico costante di miscele bituminose e calcolo del modulo complesso
VII Convegno Nazionale SIIV, Pisa 29÷30 Ottobre 1997
Autore/i: F. A., Santagata; Virgili, Amedeo
Classificazione: 4 Contributo in Atti di Convegno (Proceeding)
Abstract: VII Convegno Nazionale SIIV, Pisa 29÷30 Ottobre 1997
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/70913

Analysis of the viscoelastoplastic behaviour of bituminous mixes for the definition of a generalized rheological model
5th International Rilem Symposium
Autore/i: Santagata, F. A.; Virgili, Amedeo
Classificazione: 4 Contributo in Atti di Convegno (Proceeding)
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/40451

Indagine sperimentale sulla trazione diretta nei conglomerati bituminosi
VI Convegno Nazionale SIIV, Ancona 14÷16 Ottobre 1996
Autore/i: Bocci, Maurizio; G., Cerni; Virgili, Amedeo
Classificazione: 4 Contributo in Atti di Convegno (Proceeding)
Abstract: VI Convegno Nazionale SIIV, Ancona 14÷16 Ottobre 1996
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/44355

La determinazione della massa volumica e dei vuoti nei conglomerati bituminosi aperti
VI Convegno Nazionale SIIV, Ancona 14÷16 Ottobre 1996
Autore/i: A., Montepara; Virgili, Amedeo
Classificazione: 4 Contributo in Atti di Convegno (Proceeding)
Abstract: VI Convegno Nazionale SIIV, Ancona 14÷16 Ottobre 1996
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/70915

Formulazione teorica per il calcolo del modulo complesso dei conglomerati bituminosi
Congresso Nazionale SIIV, Ancona
Autore/i: Bocci, Maurizio; Capiluppi, G.; Virgili, Amedeo
Classificazione: 4 Contributo in Atti di Convegno (Proceeding)
Abstract: VI Convegno Nazionale SIIV, Ancona 14÷16 Ottobre 1996
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/44549

Analisi del comportamento viscoelastoplastico dei conglomerati bituminosi per la definizione di un modello reologico generalizzato
VI Convegno Nazionale SIIV, Ancona 14÷16 Ottobre 1996
Autore/i: F. A., Santagata; Virgili, Amedeo
Classificazione: 4 Contributo in Atti di Convegno (Proceeding)
Abstract: VI Convegno Nazionale SIIV, Ancona 14÷16 Ottobre 1996
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/70914

Il rilievo dell’aderenza con lo skid tester: influenza delle condizioni di prova
LE STRADE
Autore/i: Bocci, Maurizio; G., Cerni; Virgili, Amedeo
Editore: Milano: Casa editrice la fiaccola srl I 20123 Milano precedente: Milan: Touring Club Italiano Soci http://www.touringclub.it/,
Classificazione: 1 Contributo su Rivista
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/71098

Progetto e controllo delle caratteristiche di aderenza mediante la teoria dei frattali
LE STRADE
Autore/i: Canestrari, Francesco; Virgili, Amedeo
Editore: Milano: Casa editrice la fiaccola srl I 20123 Milano precedente: Milan: Touring Club Italiano Soci http://www.touringclub.it/,
Classificazione: 1 Contributo su Rivista
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/31072

Comportamento deformativo dei conglomerati bituminosi
Autore/i: Virgili, Amedeo
Classificazione: 5 Altro
Abstract: Corso sulle Pavimentazioni Stradali - Istituto di Strade e Trasporti - Facoltà di Ingegneria Ancona 22 novembre ÷13 dicembre 1994.
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/70904

La resistenza ultima delle barriere antisvio ancorate
LE STRADE
Autore/i: Bocci, Maurizio; G., Capiluppi; S., Colagrande; Virgili, Amedeo
Classificazione: 1 Contributo su Rivista
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/70903

Lo spogliamento degli aggregati nei conglomerati bituminosi: proposta di una nuova metodologia di prova
LE STRADE
Autore/i: Bocci, Maurizio; S., Colagrande; Virgili, Amedeo
Classificazione: 1 Contributo su Rivista
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/70902

LO SPOGLIAMENTO DEI BITUMI NEI CONGLOMERATI BITUMINOSI PROPOSTA DI UNA NUOVA METODOLOGIA
LE STRADE
Autore/i: Bocci, Maurizio; Colagrande, S.; Virgili, Amedeo
Editore: Milano: Casa editrice la fiaccola srl I 20123 Milano precedente: Milan: Touring Club Italiano Soci http://www.touringclub.it/,
Classificazione: 1 Contributo su Rivista
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/28784

Il metodo dinamico applicato alla progettazione integrata plano-altimetrica dei raccordi viari
LE STRADE
Autore/i: Virgili, Amedeo
Editore: Milano: Casa editrice la fiaccola srl I 20123 Milano precedente: Milan: Touring Club Italiano Soci http://www.touringclub.it/,
Classificazione: 1 Contributo su Rivista
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/25594

Le curve di frenatura a variazione continua del contraccolpo (FCP ed FCS) in relazione alla curva di frenatura di Nemesdy
LE STRADE
Autore/i: Montepara, A; Virgili, Amedeo
Editore: Milano: Casa editrice la fiaccola srl I 20123 Milano precedente: Milan: Touring Club Italiano Soci http://www.touringclub.it/,
Classificazione: 1 Contributo su Rivista
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/25593

Una curva di frenatura per infrastrutture viarie con variazione continua del contraccolpo con legge sinusoidale (FCS). Possibile utilizzazione nel campo ferroviario
INGEGNERIA FERROVIARIA
Autore/i: F. A., Santagata; A., Montepara; Virgili, Amedeo
Classificazione: 1 Contributo su Rivista
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/70901

L'assorbimento di bitume negli aggregati dei conglomerati bituminosi
LE STRADE
Autore/i: Montepara, A.; Virgili, Amedeo
Editore: Milano: Casa editrice la fiaccola srl I 20123 Milano precedente: Milan: Touring Club Italiano Soci http://www.touringclub.it/,
Classificazione: 1 Contributo su Rivista
Abstract: Dicembre
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/25591

Definizione di un modello di comportamento teorico per il calcolo delle barriere antisvio mediante analisi limite
INDUSTRIA ITALIANA DEL CEMENTO
Autore/i: Montepara, A.; Virgili, Amedeo
Editore: Pubblicemento Srl:Piazza G Marconi 25, I 00144 Rome Italy:011 39 06 54210237, EMAIL: iic@aitecweb.com, Fax: 011 39 06 5915408
Classificazione: 1 Contributo su Rivista
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/25590

Analisi di stabilità dei muri di sostegno in fase sismica: I'equilibrio limite allo schiacciamento
Autore/i: Agostinacchio, M.; Montepara, A.; Virgili, Amedeo
Classificazione: 5 Altro
Abstract: XXI Convegno Nazionale Stradale, Trieste 11÷15 Giugno 1990
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/70896

Influenza della scelta del rapporto di Poisson nella valutazione dello stato tensionale e deformativo di un multistrato
Autore/i: A., Montepara; Virgili, Amedeo
Classificazione: 5 Altro
Abstract: XXI Convegno Nazionale Stradale, Trieste 11÷15 Giugno 1990
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/70898

FCP - Una nuova curva di frenatura stradale a variazione continua del contraccolpo (legge parabolica)
Autore/i: F. A., Santagata; A., Montepara; Virgili, Amedeo
Classificazione: 5 Altro
Abstract: Giornate di Studi Superiori riguardanti l'organizzazione dei trasporti nell'integrazione economica europea. XXXI Convegno Internazionale - Trieste, 11÷19 Settembre 1990
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/70899

Formulazione di elemento finito per lo studio del multistrato in campo elastico non lineare e mezzo trasversalmente isotropo
LE STRADE
Autore/i: A., Montepara; Virgili, Amedeo
Classificazione: 1 Contributo su Rivista
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/70900

Modello di comportamento teorico delle barriere antisvio ancorate mediante analisi limite
XXI Convegno Nazionale Stradale, Trieste 11÷15 Giugno
Autore/i: Santagata, F. A.; Montepara, A.; Virgili, Amedeo
Classificazione: 4 Contributo in Atti di Convegno (Proceeding)
Scheda della pubblicazione: https://iris.univpm.it/handle/11566/40728