介绍了新型的预制装配式盖板涵施工工法,通过选取两个典型断面开展了现场试验,研究了预制装配式盖板涵台背及涵顶土压力的分布规律和土压力随填土荷载的增长规律.对涵洞盖板和侧墙的位移进行了测试,分析了盖板和侧墙构件的挠曲变形规律,并将测试所得的土压力和构件变形结果与数值模拟结果进行了对比.结果表明,预制装配式涵洞侧墙和盖板的挠度均较小,涵周土压力分布和变化规律均呈现明显的非线性,与现行《公路桥涵设计通用规范》中线性土压力理论存在较大的差异.盖板上垂直土压力中间较小,两侧支撑处较大,近似呈“U”形分布.侧墙水平土压力近似呈“3”形分布,最大土压力位于台帽与涵墙搭接处.所得结果为预制装配式涵洞构件的设计计算及搭接强度的确定提供了依据.
The new construction method of a culvert with prefabricated and assembled structural components was introduced. Two typical sections were selected for field test, the variations of the distributions of the earth pressures on the slab and the lateral earth pressures on the lateral walls were investigated, and the growth laws of the earth pressures were also obtained though the test. The displacements and deformations of the prefabricated slab and lateral walls were also explored. In addition, the calculated results of the earth pressures and the deformations from the numerical simulation were compared with that obtained form the field test. The results showed that, the deflections of the lateral walls and the slab were relatively small, the variations of the distribution and growth of the earth pressures were significantly nonlinear, which were very different from the results obtained from the linear earth pressure theory proposed by the current "General code for design of highway bridges and culverts". The vertical pressure was much smaller on the middle part than that on both sides of the slab, and its distribution was approximately shaped as "U". The distribution of the lateral earth pressures on the lateral walls was approximately shaped as "3". The maximum earth pressure locates at the junction of the cap and the lateral wall. The results of the field test can provide premise and basis for the calculations of the components and the strength in the junctions of the prefabricated culverts.