(1. Key Laboratory of Geotechnical Mechanics and Engineering of Ministry of Water Resources,Yangtze River Scientific Research Institute,Wuhan,Hubei 430010,China;2. Construction Headquarters of Puxuan Expressway of Yunnan Province,Xuanwei,Yunnan 655400,China;3. China Merchants Chongqing Communications Research and Design Institute Co.,Ltd.,
Chongqing,400067,China)
Abstract:In order to investigate the clamping effect and failure pattern of surrounding rocks as well as the limit of the pullout capacity of tunnel-type anchorage,field model tests on the conical frustum anchorage and cylindrical anchorage were conducted inside two parallel caves within the oblique cave of exploration in the anchorage area of Puli bridge. The side surface areas and the heights of two anchorage models are identical for quantitative comparing the differences of the clamping effect of surrounding rocks. The magnitude and the range of deformation before failure and the limit of load for the conical frustum anchorage are considerably larger than those for the cylindrical anchorage due to the clamping effect. For the cylindrical anchorage,brittle failure occurs remarkably in the contact area between the anchorage concrete and the surrounding rocks. For the conical frustum anchorage,the failure of the surrounding rocks occurs along the unfavourable fractures and experiences a long period of yielding deformation. The failure patterns for two anchorages are quite different. A concept of the coefficient of clamping effect and a corresponding method of calculation were suggested. The coefficients of clamping effect in the elastic period and at the period of strength limit are found to be 4.48 and 4.54 respectively. The pullout capacity induced by the clamping effect is significantly larger than the effect caused by the shear strength between the concrete and the rock mass. The clamping effect is the primary factor accounting for the pullout capacity of tunnel-type anchorage.
[1] 张奇华,胡建华,陈国平,等. 矮寨大桥基础岩体稳定问题研究[J]. 岩石力学与工程学报,2012,31(12):2 420–2 430.(ZHANG Qihua,HU Jianhua,CHEN Guoping,et al. Study of rock foundation stability of Aizhai bridge[J]. Chinese Journal of Rock Mechanics and Engineering,2012,31(12):2 420–2 430.(in Chinese))
[2] 张奇华,余美万,喻正富,等. 普立特大桥隧道锚现场模型试验研究:抗拔能力试验[J]. 岩石力学与工程学报,2015,34(1):93–103.(ZHANG Qihua,YU Meiwan,YU Fuzheng,et al. Study on field model test of tunnel-type anchorage at Puli bridge:pullout capacity test[J]. Chinese Journal of Rock Mechanics and Engineering,2015,34(1):93–103.(in Chinese))
[3] 中华人民共和国行业标准编写组. 公路悬索桥设计规范(报批稿)[S]. 北京:人民交通出版社,2002.(The Professional Standards Compilation Group of the People?s Republic of China. Design specification for highway suspension bridge(draft standard for approval)[S]. Beijing:China Communications Press,2002.(in Chinese))
[4] 夏才初,程鸿鑫,李荣强. 广东虎门大桥东锚碇现场结构模型试验研究[J]. 岩石力学与工程学报,1997,16(6):571–576.(XIA Caichu,CHENG Hongxin,LI Rongqiang. Testing study on field structure model of the east anchorage of Guangdong Humen bridge[J]. Chinese Journal of Rock Mechanics and Engineering,1997,16(6):571–576.(in Chinese))
[5] 肖本职,吴相超,彭朝全. 重庆鹅公岩大桥隧道锚碇围岩稳定性[J]. 岩石力学与工程学报,2005,24(增2):5 591–5 597.(XIAO Benzhi,WU Xiangchao,PENG Chaoquan. Stability of the anchorage wall rock of tunnel for Chongqing Egongyan bridge[J]. Chinese Journal of Rock Mechanics and Engineering,2005,24(Supp.2):5 591–5 597.(in Chinese))
[6] 朱杰兵,邬爱清,黄正加,等. 四渡河特大悬索桥隧道锚模型拉拔试验研究[J]. 长江科学院院报,2006,23(4):51–55.(ZHU Jiebing,WU Aiqing,HUANG Zhengjia,et al. Pulling test of anchorage model of Siduhe suspension bridge[J]. Journal of Yangtze River Scientific Research Institute,2006,23(4):51–55.(in Chinese))
[7] 邬爱清,彭元诚,黄正加,等. 超大跨度悬索桥隧道锚承载特性的岩石力学综合研究[J]. 岩石力学与工程学报,2010,29(3):433–441.(WU Aiqing,PENG Yuancheng,HUANG Zhengjia,et al. Rock mechanics comprehensive study of bearing capacity characteristics of tunnel anchorage for super-large span suspension bridge[J]. Chinese Journal of Rock Mechanics and Engineering,2010,29(3):433–441.(in Chinese))
[8] 胡 波,曾钱帮,饶 旦,等. 锚碇–围岩系统在拉剪复合应力条件下的变形规律及破坏机制研究——以坝陵河特大岩锚悬索桥为例[J]. 岩石力学工程学报,2007,26(4):712–719.(HU Bo,ZENG Qianbang,RAO Dan,et al. Study of deformation law and failure mechanism of anchorage-surrounding rock system under tensile-shear complex stresses—taking super-large suspension bridge on Baling river for example[J]. Chinese Journal of Rock Mechanics and Engineering,2007,26(4):712–719.(in Chinese))
[9] 李永盛. 江阴长江公路大桥北锚碇模型试验研究[J].同济大学学报:自然科学版,1995,23(2):134–140.(LI Yongsheng. Experimental study of the north anchorage of the Jiangyin Yangtze bridge[J]. Journal of Tongii University:Natural Science,1995,23(2):134–140.(in Chinese))
[10] 刘祖德. 抗拔桩基础[J]. 地基处理,1995,6(4):1–12.(LIU Zude. Uplift pile foundations[J]. Foundation Treatment,1995,6(4):1–12.(in Chinese))
[11] 刘祖德. 抗拔桩基础(续二)[J]. 地基处理,1996,7(1):11–16.(LIU Zude. Uplift pile foundations(continued II)[J]. Foundation Treatment,1996,7(1):11–16.(in Chinese))
[12] 刘祖德. 抗拔桩基础(续三)[J]. 地基处理,1996,7(2):6–17.(LIU Zude. Uplift pile foundations(continued III)[J]. Foundation Treatment,1996,7(2):6–17.(in Chinese))
[13] 刘祖德. 抗拔桩基础(续四)[J]. 地基处理,1996,7(3):8–13.(LIU Zude. Uplift pile foundations(continued IV)[J]. Foundation Treatment,1996,7(3):8–13.(in Chinese))
引用本文:
余美万1,张奇华1,喻正富2,夏国邦2,王世谷2,边智华1,汪 宏3. 基于夹持效应的普立特大桥隧道锚现场模型试验研究[J]. 岩石力学与工程学报, 2015, 34(02): 261-270.
YU Meiwan1,ZHANG Qihua1,YU Zhengfu2,XIA Guobang2,WANG Shigu2,BIAN Zhihua1,WANG Hong3. FIELD MODEL EXPERIMENT ON CLAMPING EFFECT OF TUNNEL-TYPE ANCHORAGE AT PULI BRIDGE. , 2015, 34(02): 261-270.