下伏溶洞顶板厚度对桩基承载特性影响模型试验研究

doi:10.3724/1000-6915.jrme.2024.0419

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摘要为研究下伏溶洞顶板厚度对嵌岩桩承载特性的影响，开展不同顶板厚度(1D～5D，D为试桩桩径)条件下模型桩载荷试验，揭示溶洞顶板破坏模式、荷载–位移曲线、桩身轴力和阻力分布特征、极限承载力随顶板厚度变化的规律，并建立溶洞顶板极限承载力计算模型，基于顶板破坏模式和H-B准则提出计算式，得出下伏溶洞桩基极限承载力计算方法。研究结果表明：(1) 顶板厚度为1D，2D时，顶板破坏形式为冲切破坏；顶板厚度为3D，4D时，为弯拉–冲切组合破坏；顶板厚度为5D时，为弯拉破坏；下伏溶洞顶板临界厚度为5.9D。(2) 试桩荷载–位移曲线呈陡变型，陡变点出现前，荷载–位移关系呈线性形态，荷载–位移曲线陡变点对应桩顶位移为(0.215～0.3)D，规范取0.05D位移对应荷载作为桩基极限承载力偏于保守。(3) 顶板厚度每增加1D，试桩极限承载力显著提升，但增幅由158%逐步降低至35%；当顶板厚度超过2D，试桩桩端承载比例超过90%。(4) 所建立的下伏溶洞桩基极限承载力计算方法，与试验结果的误差范围为3.29%～15.62%，吻合较好。

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	杨柏1
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	肖世国3
	覃超2
	杨源浩2
	石青叶2

关键词 ：桩基工程, 嵌岩桩, 溶洞顶板厚度, 承载特性, 模型试验

Abstract：To study the influence of the thickness of the underlying karst cave roof on the bearing characteristics of the rock-socketed pile，the load test of the model pile under different roof thickness conditions(1D–5D) was carried out. The failure mode of the karst cave roof，the load-displacement curve，the distribution characteristics of the axial force and resistance of the pile，and the variation of the ultimate bearing capacity with the roof thickness were analyzed. The calculation model of the ultimate bearing capacity of the karst cave roof is established. Based on the roof failure mode and the H-B criterion，the calculation formula is derived. The results show that：(1) when the roof thickness is 1D and 2D，the roof punching failure；when the roof thickness is 3D and 4D，the roof is bent-pulled-punched combined failure；when the roof thickness is 5D，the roof is flexural failure；the critical thickness of the underlying karst cave roof is 5.9D. (2) The load-displacement curve of the test pile is a steep change type，and the load-displacement relationship is linear before the steep change point appears. The pile top displacement corresponding to the steep change point of the load-displacement curve is(0.215‐0.3)D. The code takes 0.05D displacement corresponding to the load as the ultimate bearing capacity of the pile is conservative. (3) For every 1D increase in the roof thickness，the ultimate bearing capacity of the test pile is significantly improved，but the increasing extent is gradually reduced from 158% to 35%. When the roof thickness exceeds 2D，the bearing ratio of the pile end exceeds 90%. (4) The proposed calculation method of the ultimate bearing capacity of the pile of the underlying karst cave is compared with the experiments. The error range of results is 3.29%‐15.62%. They are in good agreement.

Key words： pile foundation rock-socketed pile thickness of karst cave roof bearing characteristics model test

引用本文:

杨柏1，2，肖世国3，覃超2，杨源浩2，石青叶2. 下伏溶洞顶板厚度对桩基承载特性影响模型试验研究[J]. 岩石力学与工程学报, 2025, 44(1): 236-247.
YANG Bai1，2，XIAO Shiguo3，QIN Chao2，YANG Yuanhao2，SHI Qingye2. Experimental study on the bearing characteristics of piles under the influence of thickness of underlying karst cave roof. , 2025, 44(1): 236-247.

链接本文:

https://rockmech.whrsm.ac.cn/CN/10.3724/1000-6915.jrme.2024.0419 或 https://rockmech.whrsm.ac.cn/CN/Y2025/V44/I1/236

[1]	中华人民共和国国家标准编写组. GB50007—2011建筑地基基础设计规范[S]. 北京：中国建筑工业出版社，2011.(The National Standards Compilation Group of People's Republic of China. GB50007—2011 Code for design of building foundation[S]. Beijing：China Architecture and Building Press，2011.(in Chinese))
[2]	中华人民共和国行业标准编写组. JGJ94—2008建筑桩基技术规范[S]. 北京：中国建筑工业出版社，2008.(The Professional Standards Compilation Group of People?s Republic of China. JGJ94—2008 Technical code for building pile foundation[S]. Beijing：China Architecture and Building Press，2008.(in Chinese))
[3]	中华人民共和国国家标准编写组. GB 50021—2001岩土工程勘察规范[S]. 北京：中国建筑工业出版社，2009.(The National Standards Compilation Group of People's Republic of China. GB 50021—2001 Code for investigation of geotechnical engineering[S]. Beijing：China Architecture and Building Press，2009.(in Chinese))
[4]	中华人民共和国行业标准编写组. DBJ15-31—2003建筑地基基础设计规范[S]. 北京：中国建筑工业出版社，2003.(The Professional Standards Compilation Group of People?s Republic of China. DBJ15-31—2003 Code for design of building foundation[S]. Beijing：China Architecture and Building Press，2003.(in Chinese))
[5]	汪华斌，刘志峰，赵文锋，等. 桥梁桩基荷载下溶洞顶板稳定性研究[J]. 岩石力学与工程学报，2013，26(2)：3 650-3 657.(WANG Huabin，LIU Zhifeng，ZHAO Wenfeng，et al. Research on stability of cave roof under pile loading in bridge construction engineering[J]. Chinese Journal of Rock Mechanics and Engineering，2013，26(2)：3 650-3 657.(in Chinese))
[6]	雷勇，陈秋南，马缤辉. 基于极限分析的桩端岩层冲切分析[J].岩石力学与工程学报，2014，37(3)：631-638.(LEI Yong，CHEN Qiunan，MA Binhui. Punching analysis of rock at pile tip base on limit analysis[J]. Chinese Journal of Rock Mechanics and Engineering，2014，37(3)：631-638.(in Chinese))
[7]	赵明华，朱志仁，黄明华，等. 考虑基桩嵌岩段侧阻的岩溶区顶板安全厚度计算[J]. 岩土力学，2018，39(11)：4 201-4 209.(ZHAO Minghua，ZHU Zhiren，HUANG Minghua，et al. Study on thickness of safety for cave roofs suffered bending failure in karst areas[J]. Rock and Soil Mechanics，2018，39(11)：4 201-4 209.(in Chinese))
[8]	赵明华，袁腾方，张永杰，等. 考虑溶洞空间形态的路基岩溶顶板稳定性分析方法[J]. 中国公路学报，2019，32(11)：109-117. (ZHAO Minghua，YUAN Tengfang，ZHANG Yongjie，et al. Stability analysis method of karst boof in subgrade based on cavern spatial form[J]. China Journal of Highway and Transport，2019，32(11)：109-117.(in Chinese))
[9]	张永杰，邓俊强，杨兴山，等. 考虑溶洞空间形态的岩溶桩基稳定性分析方法[J]. 中国公路学报，2019，32(1)：37-45.(ZHANG Yongjie，DENG Junqiang，YANG Xingshan，et al. Stability analysis method of pile foundation in karst area base on cavern spatial form[J]. China Journal of Highway and Transport，2019，32(1)：37-45.(in Chinese))
[10]	KIYOSUMI M，KUSAKABE O，OHUCHI M. Model tests and analyses of bearing capacity of strip footing on stiff ground with voids[J]. Journal of Geotechnical and Geoenvironmental Engineering，2011，137(4)：363-375.
[11]	YANG X L，HUANG F. Three-dimensional failure mechanism of a rectangular cavity in a Hoek-Brown rock medium[J]. International Journal of Rock Mechanics and Mining Sciences，2013，61：189-195.
[12]	GAO S J，WANG L C，LONG W. Variation of the ultimate bearing capacity of karst cave roof under the loading of pile foundation[J]. Electronic Journal of Geotechnical Engineering，2014，19：8 467-8 483.
[13]	JIANG C，LIU L，WU J P. A new method determining safe thickness of karst cave roof under pile tip[J]. Journal of Central South University，2014，21(3)：1 190-1 196.
[14]	CHEN D，YI C. Study on roof safe thickness of rock foundation with karst cave and karst cave-surrounding rock stability[C]// IOP Conference Series：Materials Science and Engineering，4th International Conference on Mechanics and Mechatronics Research. Xi?an：IOP Publishing，2017：012058.
[15]	NIE Q K，LI X L，WEI Y，et al. Calculation method for the critical thickness of a karst cave roof at the bottom of a socketed pile[J]. Advances in materials science and engineering，2021，2021：1-11.
[16]	徐挺. 相似理论与模型试验[M]. 北京：中国农业机械出版社，1982：14-28.(XU Ting. Similarity theory and model experiments[M]. Beijing：China Agricultural Machinery Press，1982：14-28.(in Chinese))
[17]	TANG X，HE B，YANG B，et al. Experimental study on axial stress-strain behaviour of steel fibre-reinforced steel slag micropowder UHPC[J]. Applied Sciences，2023，13(15)：8 807.
[18]	OVESEN N K. The use of physical models in design：The scaling law relationship[C]// The 7th European Conference on Soil Mechanics and Foundation Engineering. Brighton：[s. n.]，1979：318-323.
[19]	梁志强. 岩溶区嵌岩桩桩端承载力影响因素模型试验及数值模拟研究[硕士学位论文][D]. 广州：广州大学，2022.(LIANG Zhiqiang. Model test and numerical simulation study on influencing factors of bearing capacity of rock socketed pile end in karst area[M. S. Thesis][D]. Guangzhou：Guangzhou University，2022.(in Chinese))
[20]	徐芝纶. 弹性力学简明教程[M]. 北京：高等教育出版社，2018：207-211.(XU Zhilun. A concise course in elasticity[M]. Beijing：Higher Education Press，2018：207-211.(in Chinese))
[21]	王克林. 带有自由边的矩形板的重三角级数解[J]. 西安建筑科技大学学报：自然科学版，1988，(3)：47-57.(WANG Kelin. Trigonometric series solutions of rectangular plates with free edges[J]. Journal of Xi'an University of Architecture and Technology：Natural Science，1988，(3)：47-57.(in Chinese))
[22]	王效民，刘新东，汤翔. 重三角级数解一对边简支一对边自由的矩形板[J]. 山西建筑，2007，(29)：12-13.(WANG Xiaomin，LIU Dongxin，TANG Xiang，et al. Double triangular series solution of a pair of edges simply supported a pair of edges free rectangular plate[J]. Shanxi Architecture，2007，(29)：12-13.(in Chinese))
[23]	杨成永，马文辉，韩薛果，等. 局部均布荷载作用下四边支承矩形板的内力计算[J]. 湖南大学学报：自然科学版，2020，47(11)：114-119.(YANG Chengyong，MA Wenhui，HAN Xueguo，et al. Internal force calculation of four edges supported rectangular plates under local uniformly distributed load[J]. Journal of Hunan University：Natural Science，2020，47(11)：114-119.(in Chinese))