深基坑内撑式支护结构计算的综合刚度和双参数法

将吴恒立提出的用于合理计算桩顶作用水平集中荷载的推力桩的综合刚度原理和双参数法，延伸应用于作用有水平分布荷载（土压力）的深基坑围护结构上，提出其杆系有限元数值解法，对一深基坑内支撑式支护结构实例的开挖和支护过程中的各个工况进行了数值模拟分析，由实测位移试算反分析得到了合理的墙-土的综合刚度和地基土抗力双参数，与现有方法计算结果对比表明，该方法能使所得结果更接近实测值。从而说明，综合刚度原理和双参数法的杆系有限元数值解能更为可靠的计算深基坑内支撑式支护结构，具有参考应用价值。

Composite stiffness and biparameter method for analyzing retaining structures of deep foundation pits with internal braces

Composite stiffness principle with biparameter method applied to reasonable calculation of piles subjected to laterally concentrated loads on the top of piles brought forward by Wu Heng-li, is extended to be applied to retaining structures of deep foundation pits subjected to laterally distributed loads (earth pressure). Numerical method of link finite elements is brought forward. Then an engineering example of the construction process of excavation and retaining structures of a deep foundation pit with internal braces is simulated. Reasonable wall-soil composite stiffness and subgrade reaction biparameter are back-analyzed by displacement measurements. Compared with the existing methods, the results obtained by this method are closer to the measurements. So it is shown that numerical solutions of link finite elements based on composite stiffness and biparameter method can be more reliable to calculate retaining structures of deep foundation pits with internal braces; and it has the reference value for applications.