改进的基于p-y曲线的基坑围护结构计算方法

Improved calculation method of foundation pit enclosure structure based on p-y curve

基于p-y曲线(p为土水平抗力,y为侧向位移)的基坑围护结构计算方法虽然考虑了基坑内侧土体可能进入塑性状态的实际情况,但未考虑内支撑架设时围护墙已发生一定侧向位移、内支撑是在围护墙已发生初始位移后才开始工作的工程实际。针对上述不足,提出一种基于p-y曲线的、考虑内支撑架设时支撑处围护墙初始位移的基坑围护结构计算模型,建立了围护墙侧向位移计算的有限差分方程和方法,通过工程实例验证了方法的合理性。理论分析与工程实例计算结果均表明,文中提出的基于p-y曲线的基坑围护结构计算方法是合理的。

In current researches, although the calculation method of the foundation pit enclosure structure based on p-y curve has considered the actual situation for which the inside soil of the foundation pit may enter into the plastic state, it has not considered the lateral displacement of the retaining wall when the internal bracing is erected, which starts working after the retaining wall has occurred the initial displacement. In view of the above-mentioned shortcomings, this paper presents a calculation model of the foundation pit enclosure structure based on p-y curve, considering the initial displacement of the retaining wall where the internal bracings erect at the time of bracing. The finite difference equations and methods for lateral displacement calculation of enclosure wall are established; and then the rationality of the proposed method is verified by case studies. Theoretical analysis and case studies are all shown that the calculation method of the foundation pit enclosure structure based on p-y curve is reasonable.