温度与荷载耦合下农村公路混凝土路面板结构尺寸优化

SLAB-SIZE OPTIMIZATION OF RURAL ROAD CONCRETE PAVEMENT CONSIDERING THE COMBINED EFFECT OF TEMPERATURE GRADIENT AND TRAFFIC LOAD

为优化农村公路混凝土路面板结构设计以减小路面板厚度和节约成本,对板尺寸和板厚进行研究,分析正负温度梯度下交通荷载的最不利位置,建立文克尔地基上的板模型进行计算。研究结果表明:相比于板厚,板平面尺寸对板中最大拉应力的影响更大,因此可通过减小板尺寸来减小板厚;将只承受轮载作用的板称为小尺寸板,其临界板尺寸为2.0 m×2.0 m;路基反应模量对小尺寸路面板的板中最大拉应力影响不大;考虑疲劳损伤的小尺寸板在正、负温度梯度(15℃和-15℃)下的临界板厚分别为19 cm和16 cm。研究结果可以为节约成本为目的农村公路路面板结构尺寸优化设计提供参考。

For the purposes of rural road concrete pavement slab size optimization, the reduction of slab thickness has the advantage of lowering construction cost. This paper studied the slab size and thickness under positive and negative temperature gradients, and the most adverse locations in slabs where the traffic load is applied. This study conducted the finite element analysis for slabs on Winkler foundation. The research results show that： the slab size influences the maximum tensile stress developed in the slabs more than the thickness, and the thickness can be reduced by decreasing the slab size; small-bay slabs are those slabs that are only subject to the wheel loads, and the critical size of small-bay slab is 2.0 mx2.0 m; the modulus of subgrade reaction has minor impact on the maximum tensile stress of the small-bay slab; for the small-bay slab, when fatigue damage is considered, the critical thickness is 19 cm and 16 cm under positive and negative temperature gradients （15℃and -15 ℃）, respectively. The results may provide a reference to the rural road pavement structure optimization design, which leads to cost saving.