连续配筋水泥混凝土路面裂缝传荷系数三维有限元分析

3-D Finite Element Analysis of the Load Transfer Coefficient of Cracks in Continuously Reinforced Concrete Pavement

基于ABAQUS有限元软件,采用梁单元模拟纵向钢筋,根据Timoshenko梁理论,确定支撑反力的作用长度。采用三向弹簧单元模拟钢筋和混凝土界面联结,竖向(z方向)弹簧单元模拟混凝土对钢筋的支撑;刚度分配按照"贡献面积"的原则,通过在相邻混凝土面层板侧面对应结点设置三向弹簧单元,模拟集料嵌锁的传荷作用;建立并验证考虑裂缝传荷系数的CRCP三维有限元模型。利用该模型分析标准轮载作用下路面结构参数对混凝土面层板在裂缝附近的力学响应和裂缝传荷系数的影响。结果表明,增大混凝土板厚度,板边应力和裂缝传荷系数均明显减小;增大基层厚度和土基强度,板边应力和裂缝传荷系数略有减小;增大裂缝刚度,可提高裂缝的传荷系数,减小裂缝处混凝土面层板的受力。

Based on ABAQUS finite element software, beam elements is used to simulate longitudinal reinforcement and the action length of supporting counterforce is determined according to Timoshenko beam theory. Three-way spring unit is used to simulate joining between reinforcement and concrete, and vertical （z direction） spring unit to simulate concrete supporting for reinforcement; For rigidity distribution, according to ＂contribution area＂ principle, three-way spring units are set up at nodes corresponding to the side of adjacent concrete pavement, to simulate load transfer effect in aggregate interlock; CRCP 3D finite element model considering crack load transfer capability is built and verified. The model is used to analyze the effects of pavement structural parameters under standard axle load on the mechanical response and crack load transfer coefficient of concrete slabs near the crack. The results show that, an increased concrete slab thickness will obviously reduce the slab side stress and crack load transfer capability;An increased base course thickness will slightly reduce the soil base strength, slab side stress and crack load transfer capability;And an increased crack rigidity can improve crack load transfer capability and reduce the load bearing of the concrete slab at crack.