拉力型锚索各锚筋受力不均匀现象试验研究

付文光; 周凯; 卓志飞

doi:10.11779/CJGE201810009

拉力型锚索各锚筋受力不均匀现象试验研究 English Version

1. 深圳市工勘岩土集团有限公司,广东深圳 518054;
2. 深圳市冶建岩土工程有限公司,广东深圳 518054

详细信息

作者简介:
付文光(1970- ),男,深圳人,教授级高级工程师,主要从事岩土工程设计咨询、工程实践、试验研究等工作。E-mail: zgjy1992@126.com。

中图分类号: TU470
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出版历程
- 收稿日期: 2017-03-23
- 发布日期: 2018-10-24

Experimental study on uneven load phenomenon of tendons of tensile anchors

1. Shenzhen GongKan Geotechnical Group Co., Ltd., Shenzhen 518054, China;
2. Shenzhen YeJian Geotechnical Engineering Co., Ltd., Shenzhen 518054, China

摘要

摘要: 采用同步张拉、单拉及整体张拉法,在3个场地的基坑工程进行了65组土层拉力型锚索试验,结果表明,锚索整拉时：①锚筋数量较少或黏结长度较短时,锚筋实际抗拉力或浆筋极限黏结力偏低是受力不均匀的重要原因;②锚索在正常使用及承载能力极限状态下,均普遍存在着受力严重不均匀现象,明显降低了锚筋极限承载能力。锚筋受力变异系数0.15,或相对极差30%且偏离度20%,可作为判断严重不均匀程度的定量指标;③锚筋刚度系数具有很大的随机性及不确定性,大体上随着筋体自由长度的减短或受力的增加而增加;④锚筋随着受力增加,受力不均匀程度普遍增加,但严重程度下降;⑤锚筋数量越多,受力越均匀;⑥锚筋极限抗拉力可取标准值的0.8倍;⑦预张拉及提高预紧力不能改善锚筋受力不均匀程度,同步张拉是最佳改善方法。
- 同步张拉 /
- 锚筋 /
- 受力不均匀 /
- 抗拉力 /
- 极限黏结力 /
- 偏离度 /
- 刚度系数 /
- 预紧力
Abstract: Under integral tensioning of anchors, the results of 65 tensile anchor tests in 3 foundation pit projects with different tensile methods such as synchronous tension, separate tension and integral tension show that: (1) The real tensile resistance or ultimate bonding resistance is low if the number of tendons is less or the bonding length between tendon and grouting is short, and they are the important reasons for uneven loads on tendons. (2) The serious uneven load phenomenon of tendons is general under the serviceability limit state and ultimate limit state, and the ultimate load capacity of the anchor is reduced obviously. The variable coefficient 0.15, relative range 30% and deviation degree 20% can be used as the quantitative indice for estimating the severity. (3) The stiffness coefficient of tendons has much randomness and uncertainty, and it decreases along with the free length of tendons and increases along with the loads on tendons in general. (4) The degree of uneven load increases but serious degree decreases along with the loads on tendons in general. (5) The more the number of anchors, the more the uniform loads. (6) The ultimate tensile resistance of tendons can get 0.8 times the characteristic value. (7) Pretensioning and high pretension loads can not improve the unevenness degree of the tendons, while the synchronous tension method can improve it.
- synchronous tension /
- tendon /
- uneven load /
- tensile resistance /
- ultimate bonding resistance /
- deviation degree /
- stiffness coefficient /
- pretightening load

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参考文献(11)

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施引文献(3)

期刊类型引用(2)

1.	潘锐，王雷，王凤云，黄厚旭，蔡毅，蒋振华，张朋. 破碎围岩下注浆锚索锚固性能及参数试验研究. 采矿与安全工程学报. 2022(06): 1108-1115 . 百度学术
2.	付文光，邹俊峰，黄凯. 可回收锚杆技术研究综述. 地下空间与工程学报. 2021(S1): 512-522+528 . 百度学术