高填方减载式刚性涵洞受力特性模型试验研究

为了研究高填方减载式刚性涵洞结构的减载效果,利用模型试验分别对减载式刚性涵洞、采用一般减载方法的涵洞和未减载涵洞的涵顶垂直土压力和侧墙水平土压力进行对比分析。在此基础之上,建立了减载式刚性涵洞涵顶垂直土压力理论模型,推得了减载式刚性涵洞涵顶垂直土压力计算式,并将模型试验结果与理论分析结果进行了对比分析。研究结果表明,减载式刚性涵洞不仅能够有效缓解涵顶应力集中,而且与一般减载涵洞相比还能有效减小涵洞侧墙水平土压力;对于减载式涵洞涵顶垂直土压力,理论计算结果与模型试验结果一致且两者相差较小,从而验证了理论模型的适用性和正确性。

Model test on mechanical behavior of rigid load shedding culvert under high fill

For investigating the performance of load shedding culvert (LSC), model tests were conducted first. The performance of LSC was compared with those of imperfect-trench-installation culvert (ITC) and embankment-installation culvert (EC). Vertical earth pressure and horizontal earth pressure were measured in the model tests. Then, a theoretical model was established, and the formula for calculating the vertical earth pressure on the top slab of LSC was deduced. The proposed theoretical model was validated by comparing the results with those from model test. Research results illustrate that the LSC, compared EC, can effectively reduce the vertical earth pressure on the top slab. Comparing with ITC, LSC can not only improve the load reduction effect on the top slab but also reduce the horizontal earth pressure on the culvert sidewall. Theoretical results of the vertical earth pressure on the LSC top slab were consistent with the model test results, which indicate that the proposed theoretical model is correct and applicative.