移动荷载下复合夹层用于PCC+AC路面防裂效果分析

Analysis on Crack Control Effects of Composite Interlayer for PCC and AC Pavement under Moving Load

ISAC用来防治复合式路面反射裂缝虽具有一定效果,但在应对现今车辆严重超载加速路面开裂方面仍显不足,特在其中嵌入合金弹簧来增强复合夹层的防裂能力。运用三维有限元软件模拟车辆移动荷载,对路面设置复合夹层前后的动力响应特性进行比较,分析了夹层在抵抗变形和消减应力方面的效能。结果显示,复合夹层能有效的减小裂缝处沥青层底的错动程度和剪应力峰值,消散该区域应力高度集中;不同轴重时,裂缝处应力和变形峰值都与轴重基本呈线性关系,设置复合夹层后,超载对变形和受力的不利影响降低。

It has some effect to prevent reflection cracks when using ISAC for PCC and AC pavement,but it still appears insufficient in face of speeding up the pavement cracking under serious overloading of vehicles nowadays,so the alloy spring is embedded in ISAC to enhance its ability to prevent cracking.By using 3D FEM software to simulate the vehicle moving load,the dynamic response characteristics before and after setting the composite interlayer for the pavement are compared,and the performance of the interlayer in aspect of resisting deformation and reducing stress is analyzed.The results show that the composite interlayer could effectively reduce the dislocation and shear stress peak round cracks at the bottom of asphalt layer,and dissipate the high degree of stress concentration at this region;when axle load is different,the stress and deformation peak round cracks would have the linear relationship with the axle load approximately,after setting the composite interlayer,the adverse effects for overloading to deformation and force would be reduced.