沛屯地区静力触探确定预制管桩竖向承载力的方法探讨

目前多家勘察单位在江苏徐州沛屯地区进行岩土工程勘察时,按《建筑桩基技术规范》(JGJ 94-2008)中静力触探法估算的桩基竖向极限承载力与静载荷试验结果相差较大,这给工程设计和施工带来极大的困难,影响了工程的安全性和经济性。本文通过收集区内有代表性的工程的勘察报告及其桩基静载试验资料,研究比较静力触探法计算值与静载试桩值的关系,探讨了造成承载力计算误差较大的原因,然后对规范中静力触探法的计算公式进行了修正,得出了沛屯地区确定管桩承载力的经验公式,研究结果对区内实际工程具有一定的指导意义和实用价值。

Study on determination of bearing capacity of prestressed concrete pile by cone penetration test in Peitun area

The pile ultimate bearing capacity is always estimated according to technical code for building pile foundations （JGJ 94-2008 ） in the geotechnical investigation in Peitun area in Xuzhou, Jiangsu Province. The estimated capacity is quite different from the static loading test result. The matter brings many difficulties to design and construction, and has risk on Safety and economy. The calculation discrepancy causes are discussed by comparing the theoretical value and pile loading test results of the typical projects by collecting investigation and testing data. The capacity calculation formula by cone penetration test is amended and an empirical formula to determine pile bearing capacity in Peitun area is obtained. The study would be significant for the local projects.