深厚软弱土中钢管斜撑支护基坑的一种改进设计方法

An Improved Design Method for Deep Excavation in Soft Soil by Steep Pipe Raking Supports

对于大面积且开挖深度较浅软弱土基坑工程,传统的支护形式在施工空间上受到限制时常采用竖向斜撑支护体系,将结构底板作为可靠的支撑受力点,在优先考虑节约工期前提下,通过设置附加承台传递斜撑轴力的改进设计方法,结合工程案例,利用解析法进行桩身位移内力求解与理正深基坑设计软件、现场监测数据对比分析,结果表明,三种方法得出桩身位移、内力基本吻合,传力可靠,改进方法具有一定理论及工程实用性,建议工期紧张类似工程,优先采用。

In the deep excavations with very large area,if the depth of excavation is not excessive,the common excavation support method is the raking support utilizing the bottom structure as supporting points.An improved supporting method by using the additional platform without compromise the construction schedule is proposed to resist the axial force of the raking supports.The improved supporting method was verified by the analytical design method for the axial force,commercial excavation design software,and the monitoring results.It is concluded that the stress and strain in the pile are similar with three different method.