坑底局部超挖对复合土钉受力性状的影响研究

为研究基坑底部局部超挖对复合土钉结构受力性状的影响，以深圳市某基坑工程为例，运用ABAQUS分析了不同超挖深度下复合结构的受力状态，并研究了桩身嵌固深度及桩径变化对结构受力性状的影响。研究结果表明:随着超挖深度的加大，桩身及土钉受力明显恶化；桩身嵌固深度存在临界值；适当增大桩径，能减小桩身的拉应力。

Studies on the Effect of Composite Soil-nailing Force Character by Partial Overexcavation on the Pit Bottom

Taking an excavation engineering in Shenzhen as an example to study the effect of local overexcavation at the bottom of the foundation pit on the stress property of composite soil nail, the paper applied ABAQUS to analyze the stress state of this composite structure in different depth of overexcavation, furthermore, studied how the embedded depth and diameter of pile affect the stress behavior thereof. The result shows that, as the overexcavation depth increases, the stress on the pile and soil nail go worse greatly; the embedded depth of pile has critical value; and appropriate increase of pile diameter may reduce the tensile stress on the pile.