预应力矩形支护桩弯矩反算方法

INVERSION METHOD FOR CALCULATING BENDING MOMENT OF RECTANGULAR PRESTRESSED SUPPORTING PILE

预应力矩形支护桩是一种钢筋混凝土预制桩,作为新型支护桩已经在基坑工程中得到了一定的应用。为了确保深基坑的安全,需要对支护桩的弯矩承载力发挥程度有清晰了解。但由于矩形支护桩是预制桩,无法对其桩身内力进行监测,根据基坑监测所得的测斜数据进行最小二乘法曲线拟合求得支护桩变形曲线,然后通过变形曲线二次求导后反算出基坑开挖过程中支护桩的实际弯矩。在获得了支护桩弯矩承载力发挥程度的基础上,对矩形支护桩的安全状态进行评估,验证了矩形支护桩应用于基坑支护的安全性。

As a new type of supporting pile,rectangular prestressed supporting pile has been used to a certain degree in foundation pit.In order to ensure the safety of the deep foundation pit,it is necessary to get the bending moment capacity of the piles.Rectangular prestressed supporting pile is prefabricated pile,so its internal force cannot be got through the foundation pit monitoring.In this article,the actual bending moment of piles in the process of foundation excavation is estimated through fitting a curve to the inclinometer data with least square method.Moreover,based on the bending moment data,it is estimated the stability of the rectangular supporting pile and verified the security of the rectangular supporting pile applied in deep foundation pit.