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为研究路面结构在交通荷载作用下的动态响应,应用ABAQUS软件建立路面的三维有限元模型。探讨了3种路面结构在交通荷载作用下的动压应力和拉应力、水平剪应力和竖向位移等指标。研究结果表明:(1)3种路面结构的最大压应力随着深度的增加逐渐减小,且都在深度0.30m附近出现显著变化;随着所受轴载的增加,结构层面层承受的压应力也随之增大,并向深处扩散;当车载为150kN时,面层所受的压应力为0.15~0.25MPa,而车载为450kN时,基层内的压应力以达到0.15~0.25MPa;在正常行驶情况下,行驶速度为100km/h时,荷载经过时,最大压应力显著变化范围位于0~0.3m深度处;(2)3种路面结构所受的剪应力相对于压应力和拉应力来说较大,这说明汽车在行驶过程中对路面结构的剪切破坏更为明显;(3)前两种路面结构型式中的拉应力整体上呈现先增后减的变化,且都在路面面层出现较大的拉应力,第3种路面结构型式的拉应力基本上呈递增型式,但在0.3m深度以下增长缓慢,路面底基层仍然承受一定的拉应力;(4)通过将试验数据和模拟数值进行对比分析,模拟数据基本与试验实测数据一致,说明建模时所选取的参数能够较好的模拟移动行车荷载对路面的影响;将路面结构所用材料的抗折强度与无侧限抗压强度同模型的模拟值进行对比,得知不同中方案中路面的材料强度储备充分,能满足行车荷载所产生的压应力和拉应力,路面结构设计满足要求。
In order to study the dynamic response of pavement structure under traffic load, a three-dimensional finite element model of pavement is established by using ABAQUS software. The dynamic pressure stress and tensile stress, horizontal shear stress and vertical displacement of three kinds of pavement structures under traffic load are discussed. The results show that: (1) The maximum compressive stress of the three kinds of pavement structures decreases with the increase of depth, and both of them have significant changes near the depth of 0.30m. With the increase of axial load, The stress is also increased, and to the depths of diffusion; when the car is 150kN, the surface compressive stress is 0.15 ~ 0.25MPa, while the car is 450kN, the grassroots compressive stress to reach 0.15 ~ 0.25MPa; Under normal driving conditions, when the driving speed is 100km / h, the maximum range of the maximum compressive stress is located at the depth of 0 ~ 0.3m when the load passes through. (2) The shear stress of the three kinds of pavement structures is higher than the compressive stress and tension The stress is larger, which shows that the car in the process of traveling on the pavement structure of the shear damage is more obvious; (3) the first two types of pavement tensile stress in the overall increase and then decrease, and are The tensile stress of pavement layer is larger than that of the third pavement structure. The tensile stress of the pavement structure of the third pavement is basically in an increasing pattern, but it grows slowly below the depth of 0.3 m, and the pavement base layer still suffers a certain tensile stress. (4) Data and simulation values were compared and analyzed, the basic simulation data and experimental measurements The results show that the parameters selected in the modeling can better simulate the influence of moving driving load on the pavement; compare the flexural strength and unconfined compressive strength of the pavement structure with the simulation value of the model, In the program, the material strength of the pavement is well-stocked and can meet the compressive stress and tensile stress caused by traffic load. The pavement structure design meets the requirements.