图珲公路高填方涵洞竖向荷载分布试验研究

为了研究高填方涵洞顶部土压力随填土高度变化的规律以及拱效应,依据相似原理设计了宽坦沟谷沟心设涵边界条件的涵洞室内模型试验,测得不同填土高的涵洞顶部土压力和涵台外侧土压力;选取图们—珲春高速公路桩号为RK392+640处高填方涵洞作为试验涵洞,在涵顶埋设土压力盒测量不同填土高度的涵顶竖向土压力;按照《公路桥涵设计通用规范(JTG D60-2004)》计算土压力,比较并分析计算值与实测值的误差。结果表明,涵顶土压力随着填土的增加而增加,当填土达到一定高度后,高填方涵洞上方将产生拱效应,由于涵顶路基填料的特点,拱效应具有不稳定性,从而使土压力的增加幅度变小,涵顶土压力也随填土高度呈现非线性规律变化。

Experimental Study on Vertical Load Distribution of High-Stacked Culverts at Tumen-Hunchun Highway

Based on the similarity principle, for the boundary conditions of culvert located in wide valley, the laboratory model tests on culvert were designed to measure the earth pressure on culvert and culvert pier under different fill heights to find the improvement of fill on the earth pressure of high-stacked culvert and arching action. The earth pressure cells were buried on the top of high-stacked test culvert located at pile RK392+640 of Tumen-Hunchun highway to measure the vertical earth pressure under different fill heights. Meanwhile the calculations of earth pressure according to the General Code for Design of Highway Bridges and Culverts (JTG D60-2004) were obtained. The errors between the calculation results from Code and the measured results were analyzed. The results show that the earth pressure on culvert increases with the increasing of fill height, as the earth embankment is filled higher, the arching action will take place above the culvert. Because the fill is different from the rock, the arching action is unstable. The growth of the earth pressure reduces gradually and the earth pressure varies non-linearly.