This page has only limited features, please log in for full access.
A method was developed for solving the relaxation modulus of high viscosity asphalt sand (HVAS) based on the three-point bending creep test, and was verified by comparison with experimental results. In this method, firstly, a transcendental equation was obtained by the convolution, and then equations were obtained by Taylor’s formula, which were solved by Mathmatica to obtain the relaxation modulus by Newton’s method. Subsequently, the laboratory investigations of the viscoelastic parameters of the Burgers model for the HVAS by three-point bending creep tests were carried out. In addition, the method was verified by comparing the relaxation moduli with the indoor relaxation experiments. Results showed that the numerical calculation and the test data were in good agreement, and the relaxation characteristics of the HVAS were reflected more accurately. The method can be used to study the relaxation characteristics of the asphalt mixtures effectively. In addition, this study provides a research basis for road crack prevention.
Yazhen Sun; Zhangyi Gu; Jinchang Wang; Xuezhong Yuan. Research of Method for Solving Relaxation Modulus Based on Three-Point Bending Creep Test. Materials 2019, 12, 2021 .
AMA StyleYazhen Sun, Zhangyi Gu, Jinchang Wang, Xuezhong Yuan. Research of Method for Solving Relaxation Modulus Based on Three-Point Bending Creep Test. Materials. 2019; 12 (12):2021.
Chicago/Turabian StyleYazhen Sun; Zhangyi Gu; Jinchang Wang; Xuezhong Yuan. 2019. "Research of Method for Solving Relaxation Modulus Based on Three-Point Bending Creep Test." Materials 12, no. 12: 2021.
To study the dynamic response of saturated asphalt pavement under moving load and temperature load, 3-D finite element models for asphalt pavements with hydro-mechanical coupling and thermal-hydro-mechanical coupling were built based on the porous media theory and Biot theory. First, the asphalt pavement structure was considered as an ideal saturated fluid⁻solid biphasic porous medium. Following this, the spatial distribution and the change law of the pore-water pressure with time, the transverse stress, and the vertical displacement response of the asphalt pavement under different speeds, loading times, and temperatures were investigated. The simulation results show that both the curves of the effective stress and the pore-water pressure versus the external loads have similar patterns. The damage of the asphalt membrane is mainly caused by the cyclic effect of positive and negative pore-water pressure. Moreover, the peak value of pore-water pressure is affected by the loading rate and the loading time, and both have positive exponential effects on the pore-water pressure. In addition, the transverse stress of the upper layer pavement is deeply affected by the temperature load, which is more likely to cause as transverse crack in the pavement, resulting in the formation of temperature cracks on the road surface. The vertical stress at the middle point in the upper layer of the saturated asphalt pavement, under the action of the temperature load and the driving load, shows a single peak.
Yazhen Sun; Rui Guo; Lin Gao; Jinchang Wang; Xiaochen Wang; Xuezhong Yuan. Study on Dynamic Response Characteristics of Saturated Asphalt Pavement under Multi-Field Coupling. Materials 2019, 12, 959 .
AMA StyleYazhen Sun, Rui Guo, Lin Gao, Jinchang Wang, Xiaochen Wang, Xuezhong Yuan. Study on Dynamic Response Characteristics of Saturated Asphalt Pavement under Multi-Field Coupling. Materials. 2019; 12 (6):959.
Chicago/Turabian StyleYazhen Sun; Rui Guo; Lin Gao; Jinchang Wang; Xiaochen Wang; Xuezhong Yuan. 2019. "Study on Dynamic Response Characteristics of Saturated Asphalt Pavement under Multi-Field Coupling." Materials 12, no. 6: 959.
In order to represent the mechanical response laws of high-modulus asphalt pavement (HMAP) faithfully and objectively, the viscoelasticity of high-modulus asphalt mixture (HMAM) was considered, and the viscoelastic mechanical responses were calculated systematically based on moving load by numerical simulations. The performances of the HMAP in resistance to the deformation and the cracking at the bottom layer were compared with the ordinary asphalt pavement. Firstly, Lubao and Honeywell 7686 (H7686) were selected as the high modulus modifiers. The laboratory investigations of Asphalt mix-70 penetration, Asphalt mix-SBS (styrene-butadiene-styrene), HMAM-Lubao and HMAM-H7686 were carried out by dynamic modulus tests and wheel tracking tests. The conventional performances related to the purpose of using the HMAM were indicated. The master curves of the storage moduli were obtained and the viscoelastic parameters were fitted based on viscoelastic theories. Secondly, 3D pavement models based on moving loads for the viscoelastic structures were built using the non-linear finite element software ABAQUS. The wheel path was discretized in time and space to apply the Haversine wave load, and then the mechanical responses of four kinds of asphalt pavement were calculated. Finally, the sensitivity analysis was carried out. The results showed that the addition of the high modulus modifiers can improve the resistance to high-temperature rutting of the pavements. Except for the tensile strain and stress at the bottom of the underlayer, other responses decreased with the increases of the dynamic moduli and the change laws of the tensile strain and stress were affected by the range of the dynamic modulus. The tensile stress at the bottom of the asphalt layer would be too large if the modulus of the layer were too large, and a larger tensile strain would result. Therefore, the range of the modulus must be restricted to avoid the cracking due to excessive tension when using the HMAM. The resistance of the HMAP to deformation was better and the HMAP was less sensitive to load changes and could better withstand the adverse effects inflicted by heavy loads.
Yazhen Sun; Bincheng Gu; Lin Gao; Linjiang Li; Rui Guo; Qingqing Yue; Jinchang Wang. Viscoelastic Mechanical Responses of HMAP under Moving Load. Materials 2018, 11, 2490 .
AMA StyleYazhen Sun, Bincheng Gu, Lin Gao, Linjiang Li, Rui Guo, Qingqing Yue, Jinchang Wang. Viscoelastic Mechanical Responses of HMAP under Moving Load. Materials. 2018; 11 (12):2490.
Chicago/Turabian StyleYazhen Sun; Bincheng Gu; Lin Gao; Linjiang Li; Rui Guo; Qingqing Yue; Jinchang Wang. 2018. "Viscoelastic Mechanical Responses of HMAP under Moving Load." Materials 11, no. 12: 2490.
The stress-absorption layer in cement concrete pavement delays the development of reflection cracks and is good at fatigue resistance. Laboratory investigations of the anti-crack performance of the high viscous asphalt sand stress-absorption layer (HVASAL) and rubber asphalt stress-absorption layer (RASAL) were carried out by force-controlled fatigue crack propagation tests, for which three types of overlay structures with three types of pre-crack (i.e., the middle crack, the side crack, and the 45° inclined crack) were designed. A probability model was established to describe the propagation of the fatigue cracks. The fatigue crack propagation, the fatigue life, the crack propagation rate, and the crack propagation mechanism of the three types of overlay structure were compared and analyzed. The results show that the stress-absorption layers have good anti-crack fatigue performance, and that the RASAL is better than the HVASAL. The crack propagation patterns of the three types of overlay structure were found. In the double logarithmic coordinate, the curves of the three types of cracks are straight lines with different intercepts and slopes. The probability model quantifies the relationship between the crack propagation rate and ∆K. The influences of the three types of crack on the fatigue properties of the asphalt overlays are different.
Yazhen Sun; Ting Yan; Changyu Wu; Xiaofang Sun; Jinchang Wang; Xuezhong Yuan. Analysis of the Fatigue Crack Propagation Process of the Stress-Absorption Layer of Composite Pavement Based on Reliability. Applied Sciences 2018, 8, 2093 .
AMA StyleYazhen Sun, Ting Yan, Changyu Wu, Xiaofang Sun, Jinchang Wang, Xuezhong Yuan. Analysis of the Fatigue Crack Propagation Process of the Stress-Absorption Layer of Composite Pavement Based on Reliability. Applied Sciences. 2018; 8 (11):2093.
Chicago/Turabian StyleYazhen Sun; Ting Yan; Changyu Wu; Xiaofang Sun; Jinchang Wang; Xuezhong Yuan. 2018. "Analysis of the Fatigue Crack Propagation Process of the Stress-Absorption Layer of Composite Pavement Based on Reliability." Applied Sciences 8, no. 11: 2093.
The three-point bending fatigue tests were carried out in order to accurately predict the fatigue life of an asphalt mixture based on the plateau value (PV) of the dissipated strain energy ratio (DSER). The relations of the dissipated strain energy (DSE) to the stress-strength ratio, temperature and loading rate were studied, and the constructions of the mathematical models of DSE and DSER were completed based on the change laws of the DSE. The relation of the fatigue life to the PV was determined based on the analysis of damage evolution, based on which the fatigue equation was established and used to predict the fatigue life. The results show that the change laws of DSE and DSER can be well described by the proposed mathematical models. The PV is defined as the average value of the DSER in the second stage and the fatigue life decreases in power function with the increase of PV, based on which the fatigue equation of Nf = A(PV)B was established, and the established fatigue equation is very close to that is used in the MEPDG. The fatigue equation can well predict the fatigue life asphalt mixture.
Yazhen Sun; Chenze Fang; Jinchang Wang; Zuoxin Ma; YouLin Ye. Energy-Based Approach to Predict Fatigue Life of Asphalt Mixture Using Three-Point Bending Fatigue Test. Materials 2018, 11, 1696 .
AMA StyleYazhen Sun, Chenze Fang, Jinchang Wang, Zuoxin Ma, YouLin Ye. Energy-Based Approach to Predict Fatigue Life of Asphalt Mixture Using Three-Point Bending Fatigue Test. Materials. 2018; 11 (9):1696.
Chicago/Turabian StyleYazhen Sun; Chenze Fang; Jinchang Wang; Zuoxin Ma; YouLin Ye. 2018. "Energy-Based Approach to Predict Fatigue Life of Asphalt Mixture Using Three-Point Bending Fatigue Test." Materials 11, no. 9: 1696.
Laboratory predictions for the fatigue life of an asphalt mixture under cyclic loading based on the plateau value (PV) of the permanent deformation ratio (PDR) were carried out by three-point bending fatigue tests. The influence of test conditions on the recovery ratio of elastic deformation (RRED), the permanent deformation (PD) and PDR, and the trends of RRED, PD, and PDR were studied. The damage variable was defined by using PDR, and the relation of the fatigue life to PDR was determined by analyzing the damage evolution process. The fatigue equation was established based on the PV of PDR and the fatigue life was predicted by analyzing the relation of the fatigue life to the PV. The results show that the RRED decreases with the increase of the number of loading cycles, and the elastic recovery ability of the asphalt mixture gradually decreases. The two mathematical models proposed are based on the change laws of the RRED, and the PD can well describe the change laws. The RRED or the PD cannot well predict the fatigue life because they do not change monotonously with the fatigue life, and one part of the deformation causes the damage and the other part causes the viscoelastic deformation. The fatigue life decreases with the increase of the PDR. The average PDR in the second stage is taken as the PV, and the fatigue life decreases in a power law with the increase of the PV. The average relative error of the fatigue life predicted by the fatigue equation to the test fatigue life is 5.77%. The fatigue equation based on PV can well predict the fatigue life.
Yazhen Sun; Chenze Fang; Jinchang Wang; Xuezhong Yuan; Dong Fan. Method of Fatigue-Life Prediction for an Asphalt Mixture Based on the Plateau Value of Permanent Deformation Ratio. Materials 2018, 11, 722 .
AMA StyleYazhen Sun, Chenze Fang, Jinchang Wang, Xuezhong Yuan, Dong Fan. Method of Fatigue-Life Prediction for an Asphalt Mixture Based on the Plateau Value of Permanent Deformation Ratio. Materials. 2018; 11 (5):722.
Chicago/Turabian StyleYazhen Sun; Chenze Fang; Jinchang Wang; Xuezhong Yuan; Dong Fan. 2018. "Method of Fatigue-Life Prediction for an Asphalt Mixture Based on the Plateau Value of Permanent Deformation Ratio." Materials 11, no. 5: 722.