采动区设缝沥青路面结构力学性能研究

A study on the mechanical property of asphalt pavement with deformation joints in subsidence area

穿越煤矿采动区的公路,由于地下采煤的影响,地面将不均匀沉降,路面结构产生附加应力,其值有可能超过道路允许应力使路面结构破坏,但传统沥青路面设计一般不考虑地基不均匀变形的影响,其抗变形能力有限。提出一种抗变形路面结构——设变形缝沥青路面结构。采用弹性力学理论推导地表不均匀变形引起沥青路面结构附加应力的解析表达式;通过室内足尺寸试验模拟,得出在相同曲率变形条件下,设缝模型比不设缝模型不均匀变形量和附加应力有显著降低,说明设缝沥青路面结构可以减小路面破坏几率;建立路面结构与地基相互作用的有限元模型,分析路面结构在地基不均匀沉降下的受力性能,给出变形缝的合理宽度和一些设计设缝沥青路面结构的建议。

The road across coal mining area may experience differential subsidence due to underground mining, and thus lead to additional stress to the pavement structure. When the addition stress is larger than the strength of the pavement structure, damage occurs. In traditional design method, differential settlement of subgrade is ignored, and pavement structure has little anti-deformation capacity. A new pavement Structure, asphalt pavement with deformation joints, is presented. Based on elasticity theory, a mathematical expression for calculating additional stress due to differential settlement is presented. Model experiment finds out that differential settlement and additional stress in the pavement structure with deformation joints would be more significantly reduced than those without deformation joints subjected the same deformation. Pavement structure with deformation joints has low damage probability than that without joints. Based on ANSYS, a FEM model on the interaction of pavement structure with joints and subgrade is established and the mechanical response of pavement structure to different settlement is analyzed. Suggestions on rational width of joints and on the design of asphalt pavement structure with joints are presented.