竖向管式格栅加筋碎石桩承载力计算方法

Calculation method of ultimate bearing capacity of gravel pile reinforced with tube-geogrids

为了研究竖向管式格栅加筋碎石桩承载力的计算方法,根据其受力特性,提出可能发生破坏的3种模式:桩顶鼓出破坏、格栅套筒下方碎石桩鼓出破坏和桩端刺入破坏。基于Brauns的计算方法,给出了桩顶鼓出破坏模式的承载力计算公式,推导出了格栅套筒下方碎石桩鼓出破坏模式的单桩极限承载力的理论计算方法,给出了根据格栅抗拉强度来判断破坏模式的计算公式。对现场试验的算例进行了复核验算,将计算结果与现场静载荷实验结果进行了比较,两者吻合较好。

According to mechanical characteristics,the three failure modes that may occur includes pile head bellying,bellying failure of gravel below tube-geogrids and penetration failure of pile bottom.Based on the method of Brauns,the bearing capacity formula of pile head bellying mode was put forward.In addition,the bearing capacity calculation method of the mode of bellying failure of gravel below tube-geogrids was also deduced.The calculational formula to estimate the failure mode by tensile strength of geogrids was put forward.The conclusion is proved by the results of the field experiment.