【目的】研究沥青路面表面裂缝在动荷载作用下的扩展行为,分析完整沥青路面结构和含表面裂缝结构的负荷响应,探讨应力强度因子K2随着荷载变化的规律,以及表面裂缝在扩展过程中K2的敏感性,为公路工程中路面结构抗裂设计提供一定理论依据。【方法】应用有限元软件ABAQUS建立沥青路面表面裂缝结构模型,基于动力学理论对交通荷载作用下沥青路面结构进行数值计算。【结果】动荷载作用下,完整沥青路面的表面弯沉较静态荷载有所减小,随着裂缝扩展深度的增大,弯沉值会逐渐增大; 动应力强度因子K2的变化曲线较荷载变化曲线具有一定的滞后性,且最大值大于静态荷载下K2的值; 表面裂缝向下扩展过程中,K2在扩展前期增长速率较快,扩展至面板厚度一半后,K2的增长速率逐渐放缓; 减小面层模量、增大基层模量和厚度,能够较好地抑制表面裂缝的扩展,其余参数则影响较小; K2随着行车荷载的增大呈线性增长趋势,裂缝扩展越深K2增加越显著。【结论】延长含表面裂缝的沥青路面结构的使用寿命,较好的方法是减小面层动态模量,适当增大基层的动态模量以及增大基层的厚度。
Abstract
【Objective】This study is aimed at exploring behavior of the asphalt-paved surface crack propagation under dynamic loads and providing fundamental theory for the crack propagation estimation. The loading response of the asphalt pavement and asphalt pavement structure with surface crack were investigated. The stress intensity factor K2 along with the change of load and the sensitivity in the course of surface crack propagation was examined.【Method】Using ABAQUS software, the finite element model for the asphalt pavement surface crack was established. Based on the dynamics theory, the structure of vehicle loads acting on the asphalt pavement was analyzed by using the finite element method. 【Result】Under the dynamic loads,the perfect asphalt pavement structure has less deflection than that under static loads and the pavement deflection increases with the propagation of crack depth. The variation curve of the dynamical stress intensity factor K2 lags behind the variation curve of vehicle loads and the maximum value is greater than K2 under static loads. During the development of the surface crack, the propagation rate of K2 increases rapidly initially, and then gradually slows down after the crack is deeper than the half of the thickness. It can inhibit the development of the surface crack by increasing the modulus and thickness of the foundation and decrease the modulus of surface layer. In addition to the effect of the modulus, the other parameters slightly affect the crack propagation. K2 increases linearly as the increase in dynamic loads, and K2 increases significantly with the development of cracks.【Conclusion】In order to prolong the life of asphalt pavement with surface cracks, it is suggested to decrease the dynamic modulus of surface layer, and appropriately increase the dynamic modulus and thickness of the foundation.
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参考文献
[1] 沈金安. 沥青及沥青混合料路用性能[M]. 北京:人民交通出版社,2001.
[2] SVASDISANT T, SCHORSCH M, BALADI G, et al. Mechanistic analysis of top-down cracks in asphalt pavements[J].Transportation Research Record Journal of the Transportation Research Board, 2002, 1809(1):126-136.
[3] 朱登元, 姚占勇. 含裂缝沥青路面结构轮载响应分析[J].山东大学学报(工学版), 2013, 43(4): 74-79. ZHU D Y, YAO Z Y. Mechanical responses of asphalt pavement structure with a crack under wheel load[J]. Journal of Shandong University(Engineering Science), 2013, 43(4): 74-79.
[4] 罗睿, 黄晓明. 沥青路面表面裂缝应力强度因 子计算方法研究[J]. 公路交通科技, 2002,19(1): 12-15. LUO R, HUANG X M. Research on the method to calculate the stress intensity factor of asphalt pavement’s edge crack[J]. Journal of Highway and Transportation Research and Development, 2002,19(1): 12-15.
[5] 王宏畅, 李国芬, 黄晓明. 高等级沥青路面表面裂缝扩展规律及寿命研究[J]. 公路交通科技, 2007,24(7): 10-14. WANG H C, LI G F, HUANG X M. Research on Propagation and fatigue life of asphalt pavement surface crack[J]. Journal of Highway and Transportation Research and Development, 2007,24(7): 10-14.
[6] 王金昌, 朱向荣, 叶俊能, 等. 动荷载作用下含裂缝公路结构体的应力强度因子[J]. 振动工程学报, 2003,16(1): 114-118. WANG J C, ZHU X R, YE J N, et al. SIF of Pavements with cracks under dynamic loading[J]. Journal of Vibration Engineering, 2003,16(1): 114-118.
[7] 张珊珊. 沥青路面Top-Down裂缝开裂机理研究[D]. 西安: 长安大学, 2012.
[8] 段雨芬. 裂缝深度对沥青路面动力响应的影响[J]. 石油沥青, 2014, 28(4): 33-37. DUAN Y F.Influence of crack depth on dynamic response of asphalt pavement[J]. Petroleum Asphalt, 2014, 28(4): 33-37.
[9] 钟阳, 李超. 表面裂缝对沥青路面结构的影响分析[J]. 山西建筑, 2010, 36(34): 271-272. ZONG Y, LI C. Analysis of the effect of surface crack on asphalt pavement structure[J]. Shanxi Architecture, 2010, 36(34): 271-272.
[10] CLYNE T R, LI X, MARASTEANU M O, et al. Dynamic and resilient modulus of Mn/Dot asphalt Mixtures[R]. Minneapolis:University of Minnesota, 2003.
[11] 程箭, 许志鸿, 李淑明, 等. 水泥稳定碎石静态模量与动态模量比较[J]. 建筑材料学报, 2010, 12(1): 63-66. CHENG J, XU Z H, LI S M, et al. Comparison of compressive resilient modulus and dynamic modulus of cement-stabilized Macadam[J]. Journal of Building Materials, 2010, 12(1): 63-66.
[12] 王宏畅, 黄晓明. 级配碎石沥青路面反射裂缝扩展及寿命研究[J]. 武汉理工大学报, 2010, 32(7): 65-68. WANG H C, HUANG X M.Research on crack propagation and fatigue life of granular base asphalt pavement[J]. Journal of WuHan University of Technology, 2010, 32(7): 65-68.
[13] 李超. 交通荷载作用下沥青路面开裂的有限元分析[D]. 大连:大连理工大学, 2010. LI C. Analysis using finite element method for cracking in asphalt pavement under traffic load[D]. Dalian: Dalian University of Technology,2010.
[14] 黄仰贤. 路面分析与设计[M]. 北京:人民交通 出版社, 1998.
[15] 郦正能. 应用断裂力学[M]. 北京: 北京航空航天出版社, 2012.
[16] 廖公云, 黄晓明. ABAQUS有限元软件在道路工程中的应用[M]. 南京: 东南大学出版社, 2008.
基金
基金项目:江苏省普通高校学术学位研究生科研创新计划(KYLX_0884)
第一作者:葛辉(419314401@qq.com)。*通信作者:王宏畅(seuwhc@163.com),副教授,博士。
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