桩锚支护体系侧壁土压力分布规律

Distribution regularity of earth pressure on side wall of pile-anchor supporting system

为研究作用在基坑工程桩锚支护体系上的土压力,结合郑州某快速通道工程现场实测数据,分别计算主动、被动、静止土压力和4种非极限状态下土压力模型的结果,再与实测土压力对比,讨论各种模型的适用性.研究结果表明:当准主动位移很小时,宰金珉、徐日庆和陈页开模型的结果与静止土压力基本相等,卢国胜模型结果偏小,实测土压力介于静止和主动土压力之间;当准被动位移很小时,徐日庆和陈页开模型的结果与静止土压力基本相等,宰金珉模型结果约为静止土压力的1.3倍,卢国胜模型结果偏大;对于地质条件较好的实际工程,桩锚支护体系支护桩水平位移值小于3 mm时,在设计施工中,土压力值可按静止土压力考虑.

In order to investigate the distribution regularity of the earth pressure in pile-anchor supporting system of foundation pit engineering,the field measured data of an express way project in Zhengzhou was employed to calculate respectively the active,passive,static earth pressure and the results determined by earth pressure model under four nonlimit states compare them to their actually measured data,and the applicability of various models was discussed.The result showed that when the quasi-active displacement was small,the results of Zai Jinmin model,Xu Riqing model and Chen Yekai model would be approximately equal to the static earth pressure while the result of Lu Guosheng model would be small and the actually measured value would be between the static earth pressure and the active earth pressure.When the quasi-passive displacement was small,the results of Xu Riqing model and Chen Yekai model would be almost equal to the static earth pressure.The result of Zai Jinmin model would be approximately 1.3 times of the static earth pressure.The result of Lu Guosheng model would be relatively larger.For a practical project with sound geological condition and 3 mm less horizontal displacement of supporting pile in pile-anchor supporting system,the static earth pressure could be taken as the earth pressure in design and construction of the pile-anchor supporting system.