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Preparation and Analysis of Carbon Fiber-Silicon Carbide Thermally Conductive Asphalt Concrete
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作者 Zhiyong Yang Enjie Hu +3 位作者 Lei Xi Zhi Chen Feng Xiong Chuanhai Zhan 《Fluid Dynamics & Materials Processing》 EI 2024年第4期705-723,共19页
An experimental investigation into the thermal conductivity of CF-SiC two-phase composite asphalt concrete is presented.The main objective of this study was to verify the possibility of using SiC powder instead of min... An experimental investigation into the thermal conductivity of CF-SiC two-phase composite asphalt concrete is presented.The main objective of this study was to verify the possibility of using SiC powder instead of mineral powder as the thermal conductive filler to prepare a new type of asphalt concrete and improve the efficiency of electrothermal snow and ice melting systems accordingly.The thermal conductivity of asphalt concrete prepared with different thermally conductive fillers was tested by a transient plane source method,and the related performances were measured.Then the temperature rise rate and surface temperature were studied through field heating tests.Finally,the actual ice melting efficiency of the thermally conductive asphalt concrete was evaluated using an effective electrothermal system.As shown by the experimental results,the composite made of SiC powder and carbon fiber has a high thermal conductivity.When SiC replaces mineral powder,the thermal conductivity of the asphalt mixture increases first and then decreases with the increase of carbon fiber content.In the present study,in particular,the thermal conductivity attained a peak when the carbon fiber content was 0.2%of the aggregate mass. 展开更多
关键词 Carbon fiber silicon carbide thermally conductive asphalt concrete road performance electrothermal snow melting
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Viscoelastic micromechanical model for dynamic modulus prediction of asphalt concrete with interface effects 被引量:3
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作者 董满生 高仰明 +2 位作者 李凌林 王利娜 孙志彬 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第4期926-933,共8页
A viscoelastic micromechanical model is presented to predict the dynamic modulus of asphalt concrete (AC) and investigate the effect of imperfect interface between asphalt mastic and aggregates on the overall viscoe... A viscoelastic micromechanical model is presented to predict the dynamic modulus of asphalt concrete (AC) and investigate the effect of imperfect interface between asphalt mastic and aggregates on the overall viscoelastic characteristics of AC. The linear spring layer model is introduced to simulate the interface imperfection. Based on the effective medium theory, the viscoelastic micromechanical model is developed by two equivalence processes. The present prediction is compared with available experimental data to verify the developed framework. It is found that the proposed model has the capability to predict the dynamic modulus of AC. Interface effect on the dynamic modulus of AC is discussed using the developed model. It is shown that the interfacial bonding strength has a significant influence on the global mechanical performance of AC, and that continued improvement in surface fimctionalization is necessary to realize the full potential of aggregates reinforcement. 展开更多
关键词 asphalt concrete imperfect interface rheological properties MICROMECHANICS
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Water Stability Improvement of Acid Fine Aggregate-Based Asphalt Concrete
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作者 Yihan Sun Lihua Chu +3 位作者 Yudong Cheng Fengxia Chi Chenchen Zhang Pengcheng Sun 《Fluid Dynamics & Materials Processing》 EI 2023年第8期2171-2180,共10页
In general,acid aggregates are not used in combination with asphalt concrete because of their poor compatibility with the asphalt binder,which typically results in a scarce water stability of the concrete.In the prese... In general,acid aggregates are not used in combination with asphalt concrete because of their poor compatibility with the asphalt binder,which typically results in a scarce water stability of the concrete.In the present study,the feasibility of a new approach based on the combination of acid granite fine aggregate with alkaline limestone coarse aggregate and Portland cement filler has been assessed.The mineral and chemical compositions of these three materials have first been analyzed and compared.Then,the effect of different amounts of Portland cement(0%,25%,50%,75%and 100%of the total filler by weight)on the mechanical performance and water stability of the asphalt concrete has been considered.Asphalt concrete has been designed by using the Marshall method,and the mechanical performance indexes of this material,including the Marshall stability and indirect tensile strength(ITS),have been measured together with the related water stability indexes(namely the Marshall stability(RMS)and tensile strength ratio(TSR)).The results indicate that the alkaline limestone coarse aggregate and Portland cement filler can balance the drawback caused by the acid granite fine aggregate.The asphalt concrete has good mechanical performances and water stability when the amount of common limestone powder filler replaced by cement is not less than 75%. 展开更多
关键词 LIMESTONE GRANITE portland cement asphalt concrete mechanical performance water stability
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Modeling the Impact of Testing Mode on the Viscoelastic Behavior of Asphalt Concrete
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作者 Saad Issa Sarsam 《Journal of Smart Buildings and Construction Technology》 2023年第1期16-23,共8页
The variations in the viscoelastic characteristics of asphalt concrete due to testing mode are assessed and modeled in the present investigation.Asphalt concrete mixture was prepared at its optimum asphalt binder requ... The variations in the viscoelastic characteristics of asphalt concrete due to testing mode are assessed and modeled in the present investigation.Asphalt concrete mixture was prepared at its optimum asphalt binder requirement and compacted in slab mold with the aid of roller compaction.Beam specimens of 6.2 cm width,5.6 cm depth,and 40 cm length,were obtained from the slab samples with the aid of a diamond saw,and tested using controlled stress and strain techniques under dynamic flexural stresses.The viscoelastic properties such as the phase angle,cumulative dissipated energy,permanent deformation,flexural stiffness,and micro strain were monitored and modeled among the two testing techniques.It was noticed that higher micro strain and permanent deformation are detected when testing the asphalt concrete specimens under constant strain mode.However,higher phase angle,flexural stiffness,and energy dissipation could be observed under the constant stress mode of the test. 展开更多
关键词 Stress asphalt concrete Constant strain Phase angle Cumulative dissipated energy Flexural stiffness DEFORMATION
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Performance Characterization of CR/PU Asphalt for Potential Application in Assembled Fast-Repairing Engineering
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作者 Hong Pang Ao Lu +4 位作者 Ming Xiong Chen Chen Xian Cao Xiong Xu Jing Wang 《Fluid Dynamics & Materials Processing》 EI 2024年第5期1063-1074,共12页
Conventional repairing methods for asphalt pavement have some inconveniences,such as insufficient strength,and are typically time-consuming.To address these issues,this study proposes a new technological method to des... Conventional repairing methods for asphalt pavement have some inconveniences,such as insufficient strength,and are typically time-consuming.To address these issues,this study proposes a new technological method to design and prepare a high-performance assembled asphalt concrete block for fast repair of the potholes.A series of composite modified asphalt binders with 10%crumb rubber(CR)and different dosages(0%,1%,3%,5%)of polyurethane(PU)are examined to determine the optimized binder.Subsequently,the corresponding asphalt mixtures are prepared for further comparison and assessment of engineering properties,such as moistureinduced damage,high-temperature deformation,and low-temperature cracking characteristics.The test results show that PU can significantly improve the high-temperature performance and hardness of(crumb rubber modified asphalt)CRMA binder;3%PU contributes allowing the resistance of CRMA mixture to moisture-induced damage at higher levels,particularly under water whole immersion;as 3%PU is added,the high-temperature rutting deformation resistance of the CRMA mixture increases significantly,and the low-temperature anti-cracking properties are also improved slightly.Therefore,the innovatively designed high-quality assembled fast-repairing asphalt concrete block is recommended as an appropriate option for highway maintenance. 展开更多
关键词 Composite modified asphalt crumb rubber POLYURETHANE assembled fast-repairing asphalt concrete maintenance engineering
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Bio-based rejuvenators in asphalt pavements:A comprehensive review and analytical study
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作者 Maria Chiara Cavalli Wangjie Wu Lily Poulikakos 《Journal of Road Engineering》 2024年第3期282-291,共10页
The pressing demand for sustainable advancements in road infrastructure has catalyzed extensive research into environmentally conscious alternatives for the maintenance and restoration of asphalt concrete pavements.Th... The pressing demand for sustainable advancements in road infrastructure has catalyzed extensive research into environmentally conscious alternatives for the maintenance and restoration of asphalt concrete pavements.This paper offers a comprehensive review and analysis of bio-based rejuvenators as a promising avenue for enhancing the longevity and sustainability of asphalt.Through a multifaceted exploration,it delves into various aspects of this innovative approach.Providing a thorough overview of bio-based rejuvenators,the study highlights their renewable and environmentally friendly characteristics.It conducts an in-depth examination of a wide spectrum of bio-derived materials,including vegetable oils,waste-derived bio-products,and biopolymers,through a comprehensive survey.The paper evaluates how bio-based rejuvenators enhance aged asphalt binders and mixes,effectively mitigating the adverse impacts of aging.Furthermore,it investigates how these rejuvenators address environmental concerns by identifying compatibility issues,assessing long-term performance,and evaluating economic feasibility.Finally,the paper outlines potential advancements and research pathways aimed at optimizing the utilization of bio-based rejuvenators in asphalt concrete,thereby contributing to the sustainable evolution of road infrastructure. 展开更多
关键词 Bio-based rejuvenator Bio-based asphalt concrete Bio-based asphalt mechanical performance Environmental benefit Optimized utilization of bio-based rejuvenator
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A full-section asphalt concrete waterproof sealing structure for the high-speed railway subgrade
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作者 Qinghong Fu 《Railway Sciences》 2022年第2期193-209,共17页
Purpose–This study aims to investigate the service performances of a new full-section asphalt concrete waterproof sealing structure(FSACWSS)for the high-speed railway subgrade through on-site tracking,monitoring and ... Purpose–This study aims to investigate the service performances of a new full-section asphalt concrete waterproof sealing structure(FSACWSS)for the high-speed railway subgrade through on-site tracking,monitoring and post-construction investigation.Design/methodology/approach–Based on the working state of the waterproof sealing structure,the main functional characteristics were analyzed,and a kind of roller-compacted high elastic modulus asphalt concrete(HEMAC)was designed and evaluated by several groups of laboratory tests.It is applied to an engineering test section,and the long-term performance monitoring and subgrade dynamic performance testing system were installed to track and monitor working performances of the test section and the adjacent contrast section with fiber-reinforced concrete.Findings–Results show that both the dynamic performance of the track structure and the subgrade in the test section meet the requirements of the specification limits.The water content in the subgrade of the test section is maintained at 8–18%,which is less affected by the weather.However,the water content in the subgrade bed of the contrast section is 10–35%,which fluctuates significantly with the weather.The heat absorption effect of asphalt concrete in the test section makes the temperature of the subgrade at the shoulder larger than that in the contrastive section.The monitoring value of the subgrade vertical deformation in the test section is slightly larger than that in the contrastive section,but all of them meet the limit requirements.The asphalt concrete in the test section is in good contact with the base,and there are no diseases such as looseness or spalling.Only a number of cracks are found at the joints of the base plates.However,there are more longitudinal and lateral cracks in the contrastive section,which seriously affects the waterproof and sealing effects.Besides,the asphalt concrete is easier to repair,featuring good maintainability.Originality/value–This research can provide a basis for popularization and application of the asphalt concrete waterproof sealing structure in high-speed railways. 展开更多
关键词 High-speed railway SUBGRADE asphalt concrete Waterproof sealing structure Service performance
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Numerical study of fatigue damage of asphalt concrete using cohesive zone model 被引量:5
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作者 金光来 黄晓明 +1 位作者 张苏龙 梁彦龙 《Journal of Southeast University(English Edition)》 EI CAS 2013年第4期431-435,共5页
In order to investigate the fatigue behavior of asphalt concrete, a new numerical approach based on a bi-linear cohesive zone model (CZM) is developed. Integrated with the CZM, a fatigue damage evolution model is es... In order to investigate the fatigue behavior of asphalt concrete, a new numerical approach based on a bi-linear cohesive zone model (CZM) is developed. Integrated with the CZM, a fatigue damage evolution model is established to indicate the gradual degradation of cohesive properties of asphalt concrete under cyclic loading. Then the model is implemented in the finite element software ABAQUS through a user-defined subroutine. Based on the proposed model, an indirect tensile fatigue test is finally simulated. The fatigue lives obtained through numerical analysis show good agreement with laboratory results. Fatigue damage accumulates in a nonlinear manner during the cyclic loading process and damage initiation phase is the major part of fatigue failure. As the stress ratio increases, the time of the steady damage growth stage decreases significantly. It is found that the proposed fatigue damage evolution model can serve as an accurate and efficient tool for the prediction of fatigue damage of asphalt concrete. 展开更多
关键词 fatigue damage indirect tensile fatigue test asphalt concrete cohesive zone model numerical simulation finite element method
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Effects of freeze-thaw cycles on fracture behavior of epoxy asphalt concrete 被引量:4
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作者 张勐 钱振东 《Journal of Southeast University(English Edition)》 EI CAS 2017年第1期96-100,共5页
According to the winter temperature of Peking,the freeze-thaw(FT) condition in laboratory was determined.Seven groups of epoxy asphalt concrete(EAC) specimen were exposed to different FT cycles.The flexural modulu... According to the winter temperature of Peking,the freeze-thaw(FT) condition in laboratory was determined.Seven groups of epoxy asphalt concrete(EAC) specimen were exposed to different FT cycles.The flexural modulus and fracture energy(G_F) of EAC exposed to different FT cycles were obtained through the 3-point bending test.Meanwhile,the plane strain fracture toughness(K_(IC)) of EAC was obtained through numerical simulation.The results show that the flexural modulus of the FT conditioned EAC samples decreases with the increase of FT cycles.The FT damage of flexural modulus is 60%after 30 FT cycles.Nevertheless,with the increase of FT cycles,the G_F and K_(IC) of EAC decrease first and then increase after 15 FT cycles. 展开更多
关键词 freeze-thaw cycle epoxy asphalt concrete flexural modulus fracture energy plane strain fracture toughness
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Performance evaluation of open-graded epoxy asphalt concrete with two nominal maximum aggregate sizes 被引量:6
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作者 罗桑 钱振东 薛永超 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第11期4483-4489,共7页
Open-graded friction course(OGFC) is applied to pavement surfaces to increase driving safety under wet conditions, and recently, to reduce tire/pavement noise. The durability of OGFC, however, has been a concern since... Open-graded friction course(OGFC) is applied to pavement surfaces to increase driving safety under wet conditions, and recently, to reduce tire/pavement noise. The durability of OGFC, however, has been a concern since conventional OGFC mixes last typically less than ten years before major maintenance or rehabilitation is needed. This work investigates a new open-graded asphalt mixture that uses epoxy asphalt as binder to improve mix durability. One type of epoxy asphalt that has been successfully applied to dense-graded asphalt concrete for bridge deck paving was selected. A procedure of compacting the mix into slab specimens was developed and a series of laboratory tests were conducted to evaluate the performance of the new mix, including Cantabro loss, permeability, friction, shear strength, and wheel rutting tests. Results show superior overall performance of the open-graded epoxy asphalt mix compared to conventional open-graded asphalt mix. There are also preliminary indications that the OGFC mix with 4.75-mm NMAS gradation can improve the resistance performance to raveling, while the OGFC mix with 9.5-mm NMAS gradation can improve the performance of surface friction at a high slip speed. 展开更多
关键词 open-graded concrete epoxy asphalt concrete nomina
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Self-monitoring Application of Asphalt Concrete Containing Graphite and Carbon Fibers 被引量:5
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作者 LIU Xiaoming WU Shaopeng +1 位作者 LI Ning GAO Bo 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2008年第2期268-271,共4页
The self-monitoring application of asphalt concrete containing graphite and carbon fibers using indirect tensile test and wheel rolling test were introduced. The experiment results indicate that this kind of pitch-bas... The self-monitoring application of asphalt concrete containing graphite and carbon fibers using indirect tensile test and wheel rolling test were introduced. The experiment results indicate that this kind of pitch-based composite is effective for strain/stress self-monitoring. In the indirect tensile test, for a completely conductive asphalt concrete specimen, the piezoresistivity was very weak and slightly positive, which meant the resistivity increase with the increment of tensile strain at all stress/strain amplitudes, with the gage factor as high as 6. The strain self-sensing ability was superior in the case of higher graphite content. However, when the conductive concrete was embedded into common asphalt concrete specimen as a partial structure function, the piezoresistivity was positive at all stress/strain amplitudes and with the gage factor of 13, which was much higher than that of completely conductive specimen. Thus, the strain self-sensing ability was superior when conductive asphalt concrete was taken in as a partial structure function. In the wheel-rolling test, the piezoresistivity was highly positive. At any stress amplitude, the piezoresistivity was strong, with the gage factor as high as 100, which was higher for a stress amplitude of 0.7 MPa than that of 0.5 MPa. 展开更多
关键词 asphalt concrete GRAPHITE carbon fibers SELF-MONITORING PIEZORESISTIVITY
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Discrete Element Modeling of Asphalt Concrete Cracking Using a User-def ined Three-dimensional Micromechanical Approach 被引量:6
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作者 陈俊 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2011年第6期1215-1221,共7页
We established a user-defined micromechanical model using discrete element method (DEM) to investigate the cracking behavior of asphalt concrete (AC). Using the "Fish" language provided in the particle flow code... We established a user-defined micromechanical model using discrete element method (DEM) to investigate the cracking behavior of asphalt concrete (AC). Using the "Fish" language provided in the particle flow code in 3-Demensions (PFC3D), the air voids and mastics in asphalt concrete were realistically built as two distinct phases. With the irregular shape of individual aggregate particles modeled using a clump of spheres of different sizes, the three-dimensional (3D) discrete element model was able to account for aggregate gradation and fraction. Laboratory uniaxial complex modulus test and indirect tensile strength test were performed to obtain input material parameters for the numerical simulation. A set of the indirect tensile test were simulated to study the cracking behavior of AC at two levels of temperature, i e, -10 ℃ and 15 ℃. The predicted results of the numerical simulation were compared with laboratory experimental measurements. Results show that the 3D DEM model is able to predict accurately the fracture pattern of different asphalt mixtures. Based on the DEM model, the effects of air void content and aggregate volumetric fraction on the cracking behavior of asphalt concrete were evaluated. 展开更多
关键词 discrete element method asphalt concrete cracking behavior three-dimensional simulation MICROMECHANICS
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Predicting the Dynamic Behavior of Asphalt Concrete Using Three-dimensional Discrete Element Method 被引量:4
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作者 陈俊 PAN Tongyan +2 位作者 CHEN Jingya HUANG Xiaoming LU Yang 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2012年第2期382-388,共7页
A user-defined three-dimensional (3D) discrete element model was presented to predict the dynamic modulus and phase angle of asphalt concrete (AC). The 3D discrete element method (DEM) model of AC was constructe... A user-defined three-dimensional (3D) discrete element model was presented to predict the dynamic modulus and phase angle of asphalt concrete (AC). The 3D discrete element method (DEM) model of AC was constructed employing a user-defined computer program developed using the "Fish" language in PFC3D. Important microstructural features of AC were modeled, including aggregate gradation, air voids and mastic. The irregular shape of aggregate particle was modeled using a clump of spheres. The developed model was validated through comparing with experimental measurements and then used to simulate the cyclic uniaxial compression test, based on which the dynamic modulus and phase angle were calculated from the output stress- strain relationship. The effects of air void content, aggregate stiffness and volumetric fraction on AC modulus were further investigated. The experimental results show that the 3D DEM model is able to accurately predict both dynamic modulus and phase angle of AC across a range of temperature and loading frequencies. The user- defined 3D model also demonstrated significant improvement over the general existing two-dimensional models. 展开更多
关键词 asphalt concrete dynamic modulus MICROMECHANICS discrete element method three-dimensional model uniaxial compression test
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Simulation and analysis of two-point bending fatigue test of asphalt concrete based on discrete element model 被引量:3
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作者 Cao Qingqing Liu Xiuyu +1 位作者 Wang Hao Huang Xiaoming 《Journal of Southeast University(English Edition)》 EI CAS 2017年第3期286-292,共7页
In order to investigate the fatigue performance of French high modulus asphalt concrete and the correlation between Burger's parameters and fatigue life, the virtual model of asphalt mixture trapezoidal specimen i... In order to investigate the fatigue performance of French high modulus asphalt concrete and the correlation between Burger's parameters and fatigue life, the virtual model of asphalt mixture trapezoidal specimen in the two-point bending fatigue test was constructed in discrement element software PFC3D. The initial stiffness and the maximum stress when the specimen reached fatigue were calculated. Through the comparison between virtual and single field fatigue test curves, the credibility of simulation in DEMwas verified.Then, the impacts of top controlled displacement and Burger's parameters( E_1,E_2,η_1,η_2) on the fatigue life of the specimen were explored. The simulation results indicate that the maximum stress increases with the increase in the top controlled displacement. With the increase of E_1 and the decrease of E_2 in Burger's model, the modulus of the asphalt binder increases, and the fatigue performance of the asphalt mixture enhances. η_1 and η_2 have limited influence on fatigue life compared with E_1 and E_2. 展开更多
关键词 high MODULUS asphalt concrete numericalsimulation Burger's parameters FATIGUE LIFE
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Percolation Model of Graphite-modified Asphalt Concrete 被引量:2
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作者 磨炼同 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2005年第1期111-113,共3页
The addition of graphite powder in conventional asphalt mixture can produced asp halt concrete with excellent electrical performance. Percolation theor y was employed to discuss the relation between the conductivity a... The addition of graphite powder in conventional asphalt mixture can produced asp halt concrete with excellent electrical performance. Percolation theor y was employed to discuss the relation between the conductivity and graphite con tent of graphite-modified asphalt concrete. It was found that the results of pe rcolation model are consistent with experimental values. The percolation thresho ld of graphite-modified asphalt concrete is 10.94% graphite content account for the total volume of the binder phase consisting of asphalt and graphite. The cr itical exponent is 3.16, beyond the range of 1.6-2.1 for the standard lattice c ontinuous percolation problem. Its reason is that the tunnel conduction mec hanism originates near the critical percent content, which causes this system to be not universal. Tunnel mechanism is demonstrated by the nonlinear voltage-cu rrent characteristic near percolation threshold.The percolation model is able to well predict the formation and development of conductive network in graphite- modified asphalt concrete. 展开更多
关键词 asphalt concrete electrical conduction GRAPHITE percolation model
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Micromechanical modeling of asphalt concrete fracture using a user-defined three-dimensional discrete element method 被引量:4
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作者 陈俊 汪林兵 黄晓明 《Journal of Central South University》 SCIE EI CAS 2012年第12期3595-3602,共8页
A user-defined micromechanical model was developed to investigate the fracture mechanism of asphalt concrete (AC) using the discrete element method (DEM). A three-dimensional (3D) AC beam was built using the "F... A user-defined micromechanical model was developed to investigate the fracture mechanism of asphalt concrete (AC) using the discrete element method (DEM). A three-dimensional (3D) AC beam was built using the "Fish" language provided by PFC3D and was employed to simulate the three-point bending beam test at two temperature levels: -10 ℃ and 15℃. The AC beam was modeled with the consideration of the microstructural features of asphalt mixtures. Uniaxial complex modulus test and indirect tensile strength test were conducted to obtain material input parameters for numerical modeling. The 3D predictions were validated using laboratory experimental measurements of AC beams prepared by the same mixture design. Effects of mastic stiffness, cohesive and adhesive strength on AC fracture behavior were investigated using the DEM model. The results show that the 3D DEM fracture model can accurately predict the fracture patterns of asphalt concrete. The ratio of stress at interfaces to the stress in mastics increases as the mastic stiffness decreases; however, the increase in the cohesive strength or adhesive strength shows no significant influence on the tensile strength. 展开更多
关键词 asphalt concrete fracture behavior MICROMECHANICS discrete element method three-dimensional simulation
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An Improvement in Electrical Properties of Asphalt Concrete 被引量:2
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作者 吴少鹏 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2002年第4期69-72,共4页
Materials such as Koch AH-70,basalt aggregate,limestone powder and graphite particles were used to prepare conductive asphalt concrete,which is a new type of multifunctional concrete.The mix proportion by weight was s... Materials such as Koch AH-70,basalt aggregate,limestone powder and graphite particles were used to prepare conductive asphalt concrete,which is a new type of multifunctional concrete.The mix proportion by weight was shown as follows.Fine aggregates (2.36-4.75 mm)∶fine aggregates (<2.36mm)∶limestone powder∶asphalt=120∶240∶14∶30.The content of added graphite particles ranged from 0% to 20%(by the weight of asphalt concrete).A conductive asphalt concrete with a resistivity around 10-10 3Ω·m was obtained.Special attention was paid to the effects of graphite content,graphite physical-chemical properties,asphalt content and temperature on the resistivity.Furthermore,an attempt was made to develop an electrically conductive model for asphalt concrete. 展开更多
关键词 conductive asphalt concrete electrical properties RESISTIVITY electrically conductive model
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Resistivity measurement of conductive asphalt concrete based on two-electrode method 被引量:3
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作者 杨群 李旭 王屏 《Journal of Central South University》 SCIE EI CAS 2013年第9期2599-2604,共6页
The objective of this work is to develop a novel methodology for determining real resistivity of conductive asphalt concrete based on two-electrode method.Due to an influence of contact resistance,the measured resisti... The objective of this work is to develop a novel methodology for determining real resistivity of conductive asphalt concrete based on two-electrode method.Due to an influence of contact resistance,the measured resistivity is always not equal to the real resistivity.To determine the real resistivity,a linear relationship of the measured resistivity,contact resistance and the real resistivity was established.Then experiments for six specimens with varying graphite contents were designed and performed to validate the formulation.Results of experiments demonstrate that the slope of the line represents contact resistance,and the intercept indicates the real resistivity.The effects of graphite content on contact resistance and real resistivity are also revealed.Finally,results show that the influence of contact resistance on accuracy of resisitvity measurement becomes more serious if graphite content is beyond 3%.Hence,it is the time to choose this novel methodology to determine the real resistivity of asphalt concrete by taking account of contact resistance. 展开更多
关键词 conductive asphalt concrete two-electrode method measured resistivity real resistivity contact resistance linear relationship
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Finite element analysis of road structure containing top-down crack within asphalt concrete layer 被引量:2
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作者 PIRMOHAMMAD Sadjad MAJD-SHOKORLOU Yousef 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第1期242-255,共14页
In this paper, a four-layered road structure containing a top-down crack is investigated by performing finite element analyses in ABAQUS. In this study, in addition to the vertical load of a vehicle wheel, the horizon... In this paper, a four-layered road structure containing a top-down crack is investigated by performing finite element analyses in ABAQUS. In this study, in addition to the vertical load of a vehicle wheel, the horizontal load as well as its position with respect to the crack is also considered in the analyses, and the crack tip parameters including stress intensity factors(SIFs) and T-stress are then calculated. Moreover, influence of elastic modulus and thickness of the pavement layers on the crack tip parameters is studied. Results show that the horizontal and vertical loads along with their position with respect to the crack, elastic modulus and thickness of the road layers influence the crack tip parameters(KⅠ, KⅡ and T-stress) significantly. It was also found that for the cases that the vehicle wheel is positioned near the crack plane, only the shear deformation mode is observed at the crack tip;while, for the vehicle wheel positions far from the crack, only the opening mode is observed, and between these positions, both the opening and shear deformation modes(i.e., mixed mode Ⅰ/Ⅱ) are observed at the crack tip. 展开更多
关键词 asphalt concrete top-down crack stress intensity factors T-STRESS horizontal load vertical load
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Microstructural Characteristics of Asphalt Concrete with Different Gradations by X-ray CT 被引量:5
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作者 胡靖 钱振东 +1 位作者 LIU Yang XUE Yongchao 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2017年第3期625-632,共8页
The main objective of this paper is to evaluate the effects of asphalt concrete types on the microstructural characteristics at high-temperature. Suspend-dense structure and Skeleton-dense structure were selected to i... The main objective of this paper is to evaluate the effects of asphalt concrete types on the microstructural characteristics at high-temperature. Suspend-dense structure and Skeleton-dense structure were selected to investigate the deformation of pavement at meso-scale. The internal microstructures of typical asphalt concretes, AC, SUP and SMA, were scanned by X-ray CT device, and microstructural changes before and after high-temperature damage were researched by digital image processing. Adaptive threshold segmentation algorithm(ATSA) based on image radius was developed and utilized to obtain the binary images of aggregates, air-voids and asphalt mastic. Then the shape and distribution of air-voids and aggregates were analyzed. The results show that the ATSA can distinguish the target and background effectively. Gradation and coarse aggregate size of asphalt mixtures have an obvious influence on the distribution of air-voids. The movements of aggregate particles are complex and aggregates with elliptic sharp show great rotation. The effect of gradation on microstructure during high-temperature damage promotes the research about the failure mechanism of asphalt concrete pavement. 展开更多
关键词 asphalt concrete microstructure gradation types X-ray CT digital image processing high-temperature deformation
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