不同填土管涵土压力模型试验和数值模拟研究

管涵土压力作为管涵结构设计中的主要恒定荷载,其作用模式的确定是研究的重点。通过开展三种不同填土工况(碎石、粉土、黏土)下的管土相互作用足尺物理模型试验,得到不同填土工况下马蹄形管涵土压力的作用模式,并对比填土类型对管涵土压力的影响。结果表明:试验条件下,粉土工况的管顶土压力集中效应表现最强,黏土工况最弱,碎石工况介于中间。同时采取有限元软件对模型试验进行模拟分析,与试验结果较为吻合,从而为管涵土压力的进一步研究提供科学依据。

Model test and numerical simulation of earth pressure on culvert under different earth backfill conditions

Earth pressure on the culvert is the main constant load for structure design.The distribution model of earth pressure is the focus of the study.To describe earth pressure on the horseshoe culvert,full-scale physical model tests of soil-culvert interaction were performed under three different backfill conditions and were compared.The results show that the concentration phenomenon of earth pressure on top of the stiff culvert with silt backfill becomes the most significant and it is the weakest with clay backfill under the experimental conditions.The concentration effect of gravel backfill is in the middle of the three backfill conditions.At the same time,finite element calculation was carried out to simulate the model tests.