灰岩地区承台式群锚桩基础上拔试验研究

Research on Uplift Test of Group Anchor Piles with Bearing Platform in Iimestone Area

针对灰岩地区岩石地基设计单锚桩和承台式群锚桩岩石基础,对基础进行真型上拔试验,得出单锚桩的上拔极限承载力、等代极限剪切强度和承台式群锚桩基础的上拔极限承载力;通过理论推导承台式群锚桩基础上拔极限承载力计算公式,利用反算的等代剪切强度计算出基础上拔极限承载力理论值,同时说明了其与试验值差异。试验表明承台式群锚桩基础安全可靠、经济环保,充分发挥了原状岩体力学性能,基础具有良好的抗拔性能,可用于裸露或浅埋微、中风化硬质岩石地基的输电线路工程中。

Designing the single anchor piles and group anchor piles with bearing platform in the rock ground of limestone area aimed to do true-size uplift test.It comes the ultimate uplift bearing capacity and ultimate shear strength of the single piles,and the ultimate uplift bearing capacity of group anchor piles.The paper theoretically deduces the calculation formula of ultimate uplift bearing capacity on group anchor piles with bearing platform,calculates the theoretical ultimate uplift bearing capacity by the ultimate shear strength and illustrates the difference between the theoretical values and the experimental values.The test shows group anchor piles with bearing platform is safe and reliable,economic and environmental protection,make full use of mechanics capability of undisturbed rock,have good uplift bearing capacity,therefore,the foundation can be used to the weak and medium weathered rock ground with bare or shallow buried hard rock in transmission line.