拉力型土工布加筋复合锚杆锚固界面应力传递试验分析

土工布复合锚杆是一种可应用于松散地层锚固工程的新型锚锭结构。以某滑坡治理工程为平台,开展了拉力型土工布加筋复合锚杆锚固体与破碎岩土体界面间应力传递规律的实测研究。现场试验结果表明,土工布的加筋鼓胀作用调整了锚固体与破碎岩土体接触界面的应力分布,土工布加筋复合锚杆锚固段近端存在稍长的应力协调缓冲段,随着荷载增大,黏结应力峰值向锚固段深部转移的现象不明显;实测破碎岩土体中拉力型土工布加筋复合锚杆主要抗力区域分布在3.0~13.0 m之间,即有效锚固体长度以不超过15 m为宜,过长的锚固长度对提高锚杆抗拔力意义不大;在松散破碎岩土体中应用土工布加筋复合锚杆技术能起到提高锚固力与节约成本的双重作用。

THE EXPERIMENT ANALYSIS OF STRESS TRANSFER INTO ANCHORAGE INTERFACE OF THETENSION GEOTEXTILE-COMPOSITE BOLT

Geotextile-composite bolt is a new anchor reinforcement structure used in loose strata anchor projects. A landslide control project was used as a platform to carry out pull-out test for stress transfer into anchorage interface of the tension geotextile-composite bolt. Field test results show that the geotextile reinforced ballooning effect could adjust the contact interface stress distribution between the anchor solid and broken rock mass. There exists a little long stress coordination buffer period in proximal anchoring section of geotextile-composite bolt,and the phenomenon of bond stress peak shifted to the anchoring depth is not obvious with increasing the load. Measured main resistance area of the tension geotextile-composite bolt in broken rock massis distributed between 3. 0 m to 13. 0 m. Hencl it is advisable that the effective length of anchor should be no more than 15 m,for it makes little sense to improve bolt pulling force of longer anchorage length. The application of geotextile reinforced composite bolt in broken rock mass can play a dual role of improving the anchoring force and cost-savings