温度变化对地铁深基坑支护体系的影响研究

济南地铁烈士陵园站深基坑支撑轴力监测数据表明,支撑轴力变化随大气温度变化十分明显。为深入研究温度变化对地铁深基坑支护体系的影响,运用有限元计算分析地下连续墙厚度、刚度及支撑刚度在不同温度应力下对地下连续墙水平位移和支撑轴力的影响规律。计算结果表明,连续墙墙顶水平位移和支撑轴力随温度变化呈线性变化,随着温度升高,第1道支撑轴力逐渐减小,第2道和第3道支撑逐渐增大,第3道支撑轴力增幅更大;支撑刚度对支撑轴力的影响最为显著,地下连续墙刚度对墙顶水平位移的影响最为显著,地下连续墙厚度对墙体最大水平位移影响最为显著;温度变化20℃支撑轴力的变化幅度为13%~26%。

Study on impact of temperature change on support system of metro deep foundation pit

The monitoring data of supporting axial force of deep foundation pit of Martyr Cemetery Station of Jinan metro show that the change of supporting axial force is very obvious with the change of atmospheric temperature.In order to study the impact of temperature change on the supporting system of deep foundation pit of subway,this paper analyzes the influences of the thickness,rigidity and supporting rigidity of diaphragm wall on the horizontal displacement and axial force of diaphragm wall under different temperature stress by using the finite element method.The calculation results show that the horizontal displacement and axial force of the continuous wall top change linearly with the temperature.The first axial force decreases,the second and third supports increase gradually with the temperature,and the third axial force increases more.The influence of the support stiffness on the axial force of the support is the most significant,the influence of the continuous wall stiffness on the horizontal displacement of the wall top is the most significant,and the thickness of the continuous wall on the horizontal displacement of the wall top is the most significant,while the influence of the maximum horizontal displacement of the wall is the most signifi cant.The change range of the supporting axial force is 13%-26%when the temperature changes 20℃.