岩土力学 ›› 2020, Vol. 41 ›› Issue (10): 3317-3325.doi: 10.16285/j.rsm.2020.0050

• 基础理论与实验研究 • 上一篇    下一篇

自由段先注浆对预应力锚索抗拔试验结果影响研究

杨庆光,柳 雄,刘杰,何杰,梁凌川,陈斌   

  1. 湖南工业大学 土木工程学院,湖南 株洲 412007
  • 收稿日期:2020-01-14 修回日期:2020-06-06 出版日期:2020-10-12 发布日期:2020-11-07
  • 作者简介:杨庆光,男,1979年生,博士,副教授,主要从事桩土相互作用理论等方面的教学与研究工作。
  • 基金资助:
    国家自然科学基金(No. 51978260);湖南省自然科学基金(No. 2020JJ6080,No.2020JJ6007,No.2019JJ60051)。

Influence of the pre-grouting in free segment on the pullout test of prestressed anchor cable

YANG Qing-guang, LIU Xiong, LIU Jie, HE Jie, LIANG Ling-chuan, CHEN Bin   

  1. College of Civil Engineering, Hunan University of Technology, Zhuzhou, Hunan 412007, China
  • Received:2020-01-14 Revised:2020-06-06 Online:2020-10-12 Published:2020-11-07
  • Supported by:
    This work was supported by the National Natural Science Foundation of China (51978260) and the Natural Science Foundation of Hunan Province (2020JJ6080, 2020JJ6007, 2019JJ60051).

摘要: 为了解决无法采用已注浆锚索进行抗拔试验问题,基于界面脱黏剪切模型,利用荷载传递和弹性变形理论,考虑锚索锚固段与自由段长度比Lb /La的影响,建立了采用自由段已注浆锚索抗拔试验结果评价锚索抗拔性能的方法。结果表明:自由段注浆对锚索抗拔力有较大幅度的提高,尤其是当界面剪切阶段由弹性向脱黏过渡时,提高比例快速增加,并在脱黏后逐渐趋于稳定。其次,锚索自由段与锚固段交界面处剪切位移和轴力最大,并向两端逐渐降低。随着拉拔力的提高,界面剪切位移和轴力都不断增大,同时向锚索两端的衰减速度也加快。此外,弹性阶段时剪应力曲线为山峰型,而脱黏阶段为马鞍型,并随抗拔力的提高,马鞍开口逐渐扩大。最后,锚固段与自由段长度比Lb /La对锚索极限抗拔力的影响较小,其极限抗拔力折减系数?Q取值介于0.81~0.83之间,且Lb /La =2.5时,?Q计算值仅比实测结果小6.02%,验证了本文方法的可行性。

关键词: 预应力锚索, 自由段先注浆, 界面脱黏, 抗拔特性, 荷载传递

Abstract: To overcome the drawback that the ultimate pullout resistance of prestressed anchor cable cannot be directly obtained by the pullout test, this study proposes a pullout resistance performance evaluation method of pre-stressed anchor cable based on the pullout tests on prestressed anchor cable with pre-grounting in the free segment. Based on the interfacial debonding shear model and the theories of load transfer and elastic deformation, the length ratio of the anchor segment to the free segment was considered in the evaluation method. The results indicate that pre-grouting in free segment can significantly improve the pullout resistance capability of anchor cable. When the interfacial deformation behavior transfers from an elastic manner to debonding stage, the improvement of the pullout resistance will be more pronounced, which will tend to be stable after debonding. The shear displacement and axial force at the interface of the free segment and grouting segment is the highest. With increasing the pullout force, both the shear displacement and axial force increase but the increment declines to the two ends of anchor cable. The shear stress curve is one peak type in the elastic stage and then becomes a saddle type in the debonding stage. The opening of the saddle type curve becomes larger with the improvement of the pullout resistance. Finally, the length ratio of anchoring and free segment has insignificant effects to the ultimate pullout resistance. The reduction coefficient ?Q of the ultimate pullout resistance of pre-grouting anchor cable is in the range from 0.81 to 0.83. The empirical method in paper is feasible due to the fact that merely 6.02% error is existed between the measured ultimate pullout resistance and calculation result when Lb /La is 2.5.

Key words: prestressed anchor cable, pre-grouting in free segment, interfacial debonding, pullout resistance feature, load transfer

中图分类号: 

  • TU 43
[1] 侯振坤, 唐孟雄, 胡贺松, 黎剑华, 张树文, 徐晓斌, 刘春林, . 随钻跟管桩竖向承载性能原位试验 与室内物理模拟试验对比研究[J]. 岩土力学, 2021, 42(2): 419-429.
[2] 安彩龙, 梁 烨, 王亮清, 邓 姗, 孙自豪, 范斌强, 郑罗斌. 岩质边坡楔形体锚索加固方向角三维优化设计[J]. 岩土力学, 2020, 41(8): 2765-2772.
[3] 徐毅青, 邓绍玉, 葛琦. 锚索预应力初期与长期损失的预测模型研究[J]. 岩土力学, 2020, 41(5): 1663-1669.
[4] 贺志军, 雷皓程, 夏张琦, 赵炼恒. 多层软土地基中单桩沉降与内力位移分析[J]. 岩土力学, 2020, 41(2): 655-666.
[5] 李剑, 陈善雄, 余飞, 姜领发, 戴张俊. 预应力锚索加固高陡边坡机制探讨[J]. 岩土力学, 2020, 41(2): 707-713.
[6] 贾志波, 陶连金, 史明. 地震作用下预应力锚索边坡的稳定性分析[J]. 岩土力学, 2020, 41(11): 3604-3612.
[7] 蔡雨, 徐林荣, 周德泉, 邓超, 冯晨曦, . 自平衡与传统静载试桩法模型试验研究[J]. 岩土力学, 2019, 40(8): 3011-3018.
[8] 余 瑜, 刘新荣, 刘永权, . 基坑锚索预应力损失规律现场试验研究[J]. 岩土力学, 2019, 40(5): 1932-1939.
[9] 李 宁, 杨 敏, 李国锋. 再论岩土工程有限元方法的应用问题[J]. 岩土力学, 2019, 40(3): 1140-1148.
[10] 李 林, 李镜培, 孙德安, 龚卫兵, . 考虑沉桩效应的群桩非线性荷载-沉降解析[J]. 岩土力学, 2019, 40(2): 668-677.
[11] 费 康, 戴 迪, 洪 伟, . 能量桩单桩工作特性简化分析方法[J]. 岩土力学, 2019, 40(1): 70-80.
[12] 王 伸,李化敏,李东印,王 文, . 横肋对螺纹钢树脂锚杆荷载传递的影响[J]. , 2018, 39(8): 2805-2813.
[13] 陆清元,罗 强,蒋良潍, . 路堤下刚性桩复合地基桩-土应力比计算[J]. , 2018, 39(7): 2473-2482.
[14] 严敏嘉,夏元友,刘婷婷. 地震作用下预应力锚索加固顺层岩坡极限分析[J]. , 2018, 39(7): 2691-2698.
[15] 刘永权,刘新荣,谢应坤,余 瑜, . 基坑预应力锚索初始张拉锁定值取值规律探讨[J]. , 2018, 39(6): 2164-2174.
Viewed
Full text


Abstract

Cited

  Shared   
  Discussed   
[1] 姚仰平,侯 伟. 土的基本力学特性及其弹塑性描述[J]. , 2009, 30(10): 2881 -2902 .
[2] 张力霆,齐清兰,魏静,霍倩,周国斌. 淤填黏土固结过程中孔隙比的变化规律[J]. , 2009, 30(10): 2935 -2939 .
[3] 张其一. 复合加载模式下地基失效机制研究[J]. , 2009, 30(10): 2940 -2944 .
[4] 易 俊,姜永东,鲜学福,罗 云,张 瑜. 声场促进煤层气渗流的应力-温度-渗流压力场的流固动态耦合模型[J]. , 2009, 30(10): 2945 -2949 .
[5] 张明义,刘俊伟,于秀霞. 饱和软黏土地基静压管桩承载力时间效应试验研究[J]. , 2009, 30(10): 3005 -3008 .
[6] 黄平路,陈从新,肖国峰,林 健. 复杂地质条件下矿山地下开采地表变形规律的研究[J]. , 2009, 30(10): 3020 -3024 .
[7] 吴 亮,钟冬望,卢文波. 空气间隔装药爆炸冲击荷载作用下混凝土损伤分析[J]. , 2009, 30(10): 3109 -3114 .
[8] 周晓杰,介玉新,李广信1. 基于渗流和管流耦合的管涌数值模拟[J]. , 2009, 30(10): 3154 -3158 .
[9] 吴昌瑜,张 伟,李思慎,朱国胜. 减压井机械淤堵机制与防治方法试验研究[J]. , 2009, 30(10): 3181 -3187 .
[10] 崔皓东,朱岳明. 二滩高拱坝坝基渗流场的反演分析[J]. , 2009, 30(10): 3194 -3199 .