高灵敏度淤泥质土水平支撑对钢板桩基坑稳定性影响研究

THE STABILITY STUDY OF THE STEEL SHEET PILE FOUNDATION PIT WITH THE HORIZONTAL BRACE

以灌云四队102.5 MW陆上风电场项目为研究对象,通过实测及数值模拟,研究水平支撑对钢板桩基坑稳定性的影响。结果表明,对于高灵敏度淤泥质土,当仅设置钢板桩作为基坑围护方案时,钢板桩顶部变形及弯矩均较大,桩身进入塑性,无法保证基坑的稳定性。而当钢板桩顶部设置水平腰梁及斜撑后,钢板桩顶部变形及桩身变形均较小,钢板桩处于弹性阶段,基坑处于稳定状态。说明对于高灵敏度淤泥质软土地区,设置水平支撑可保证钢板桩基坑的稳定性。将有限元计算结果与实测桩顶变形值相对比,发现有限元结果比实测结果约偏大10%。

In this paper,the 102.5 MW onshore wind farm project of Guanyun fourth-team was studied.The numerical simulation and the testing were used to analyze the influence of horizontal brace on the stability of steel sheet pile foundation pit.The results showed that for highly sensitive muddy soil,without the horizontal waist beam and diagonal brace,the top deformation and bending moment of steel sheet piles were huge,and the foundation pit was instability.Fortunately,with the setting of the horizontal waist beam and diagonal brace,the deformation of the top of the steel sheet pile and the pile shaft were small,the pile was in the elastic stage,and the foundation pit was in a stable state.It showed that the steel sheet piles with horizontal supports was useful in the highly sensitive muddy soft soil area.The finite element results were increased by 10%than the testing values.