基于旧路面破碎效果的加铺层结构荷载适应性研究

Study on Load Adaptability of Overlay Structure Based on Crushing Effect of Existing Pavement

为了探索旧水泥混凝土板破碎后的模量变异性对路面加铺结构承载力的影响规律,构建了路面加铺层结构及水泥混凝土路面破碎层和基层的有限元数值模型,分析了旧水泥路面不同破碎效果下加铺层结构路面弯沉、层底拉应力和面层最大剪应力的变化规律。结果表明:破碎混凝土板顶面回弹模量大于250 MPa时加铺层厚度可适当减小,破碎混凝土板顶面回弹模量在170~250 MPa之间时应增大加铺层厚度,破碎混凝土板顶面回弹模量小于170 MPa时应增加基层厚度,提高加铺层承载力。

In order to explore the influence of modulus variability of existing cement concrete slabs on the bearing capacity of pavement overlay structure,the finite element model of the overlay structure and the broken layer and base of cement concrete pavement was constructed,and the deflection and tensile stress of overlay structure under different crushing effect of existing cement pavement were analyzed.And the variation law of maximum shear stress in surface layer was also studied.The results show that the thickness of overlay can be reduced appropriately when the modulus of resilience of broken concrete slab is greater than 250 MPa;the thickness of overlay should be increased when the modulus of resilience of broken concrete slab is between 170 MPa and 250 MPa;and the thickness of base should be increased when the modulus of resilience of broken concrete slab is less than 170 MPa,so as to increase the bearing capacity of the overlay.