基于SMW工法的基坑围护结构安全性分析

目的分析基于SMW工法的基坑围护结构的安全性,控制围护墙体变形不致超出墙体承载能力范围.方法根据深基坑工程中常规监测所得的围护墙体测斜变形曲线,首先,通过多项式拟合的测斜曲线方程求解变形曲率,再将其带入材料力学纯弯曲梁弯矩计算公式求得型钢弯矩.其次,根据型钢材料与型号,计算型钢最大容许弯矩.最后利用反算得到的弯矩值与型钢设计容许弯矩值相比较.结果得到型钢抗弯曲承载力的发挥程度,从而判断SMW工法基坑围护结构的强度安全状态.结论该方法应用简便,能够使工程管理者及时了解基坑围护结构内力的发展情况,以便于为提前采取有效措施,避免工程事故的发生,提供有效帮助.

Security Analysis of SMW Retaining Wall in a Pit Excavation

In order to analyze the remaining bearing capacity of SMW retaining wall,control its lateral deformation within the range of bearing capacity,the relation between the bending moment of SMW retaining wall and the field survey results of lateral deformation can be established through the relative relation between bending moment and distortion.The details of the steps to calculate bending moment are introduced: First,the curvatures of the lateral deformation curves are obtained by derivation polynomial fitting equations.Then,the bending moment of the shaped steel is figured out according to the pure bending beam theory of material mechanics.Finally,the remaining bearing capacity of SMW shaped steel is known through calculating bending moment divided by its allowable moment.With this method,in deep foundation pits,the engineers will learn the surplus bending moment capability in time during the pit excavation and take action to avoid the SMW retaining walls destruction before the bending moments achieve their limit.