Influence of Partial Over-excavation on Safety Performance of Excavation Retained by Cantilever Contiguous Retaining Piles

LEI Ya-wei; ZHENG Gang; CHENG Xue-song; HUANG Tian-ming; LI Xi-yuan

doi:10.11988/ckyyb.20190563

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Journal of Changjiang River Scientific Research Institute ›› 2020, Vol. 37 ›› Issue (9) : 70-78. DOI: 10.11988/ckyyb.20190563

ROCKSOIL ENGINEERING

Influence of Partial Over-excavation on Safety Performance of Excavation Retained by Cantilever Contiguous Retaining Piles

LEI Ya-wei^1,2, ZHENG Gang^1,3, CHENG Xue-song^1,3, HUANG Tian-ming^1,4, LI Xi-yuan¹

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Abstract

Although collapse cases caused by partial over-excavation are seen frequently, studies on the overall safety performance and the progressive collapse mechanism caused by partial over-excavation are still in lack. In this study, the load transfer mechanism of cantilever contiguous retaining piles of long strip excavation subjected to partial over-excavation were investigated by finite difference method and model test. Results revealed that with the increase of over-excavation depth, the internal force of the piles beyond over-excavation zone increased by a large margin due to soil arch effect, while the bending moment of piles within over-excavation zone increased first and then decreased or continued to decrease. When the excavation depth in a large area remained the same, the increments in bending moment and displacement of adjacent piles intensified gradually and tended to be stable along with the widening of partial over-excavation range. The research results reveal the load transfer rules reflecting the influence of partial over-excavation on internal force of piles.

Key words

excavation collapse / cantilever contiguous piles / partial over-excavation / finite difference method / bending moment of piles

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LEI Ya-wei, ZHENG Gang, CHENG Xue-song, HUANG Tian-ming, LI Xi-yuan. Influence of Partial Over-excavation on Safety Performance of Excavation Retained by Cantilever Contiguous Retaining Piles[J]. Journal of Changjiang River Scientific Research Institute. 2020, 37(9): 70-78 https://doi.org/10.11988/ckyyb.20190563

References

[1] 张瑾. 基于实测数据的深基坑施工安全评估研究[D]. 上海:同济大学, 2008.
[2] CHEN R P, LI Z C, CHEN Y M, et al. Failure Investigation at a Collapsed Deep Excavation in Very Sensitive Organic Soft Clay[J]. Journal of Performance of Constructed Facilities, 2013, 29(3): 04014078. doi: 10.1061/(ASCE)CF.1943-5509.0000557.
[3] 孙海忠. 关于上海某基坑坍塌事故的分析研究[J]. 地下空间与工程学报,2012,8(增刊): 1743-1746.
[4] 周勇, 郭楠, 杨校辉, 等. 某桩锚支护深基坑超挖变形分析与加固处理[J]. 地下空间与工程学报, 2015,11(增刊1): 211-216.
[5] 龚晓南. 关于基坑工程的几点思考[J]. 土木工程学报, 2005, 38(9): 99-102.
[6] 吴铭炳, 林大丰, 戴一鸣, 等. 坑中坑基坑支护设计与监测[J]. 岩土工程学报, 2006,28(增刊): 1570-1572.
[7] 李忠超,陈仁朋,陈云敏,等.软黏土中某内支撑式深基坑稳定性安全系数分析[J]. 岩土工程学报,2015,37(5): 769-775.
[8] 惠冰. 某桩锚支护深基坑失稳破坏过程分析与加固处理[J]. 施工技术,2015,44(增刊): 112-116.
[9] TAN Y, WEI B. Observed Behaviors of a Long and Deep Excavation Constructed by Cut-and-Cover Technique in Shanghai Soft Clay[J]. Journal of Geotechnical and Geoenvironmental Engineering, 2011, 138(1): 69-88.
[10]谢秀栋,刘国彬. 深基坑施工围护结构变形的时间特性研究[J]. 地下空间与工程学报, 2012,8(6): 1261-1266.
[11]黄广龙, 张枫, 卫敏, 等. 某软土深基坑险情分析与处理[J]. 岩土力学,2009,30(6): 1735-1740.
[12]胡辉,汤连生,林兴立,等.外坑支护结构转动时坑间被动区土拱效应分析[J]. raybet体育在线院报,2015,32(4): 101-108.
[13]汤瑞,王强,过令,等.不同超挖厚度对围护结构及周边环境的影响[J].raybet体育在线院报,2016,33(4):105-110.
[14]江杰,胡何,冯野,等.坑中坑土体加固对悬臂式支护结构的影响分析[J].raybet体育在线院报,2017,34(3): 58-62,66.
[15]孙剑平,魏焕卫,江宗宝, 等. 影响复合土钉墙的变形因素的实测分析[J].岩土工程学报,2010,32(增刊1): 430-434.
[16]郑刚, 程雪松, 张雁. 基坑环梁支撑结构的连续破坏模拟及冗余度研究[J]. 岩土工程学报, 2014, 36(1): 105-117.
[17]郑刚, 程雪松, 刁钰. 基坑垮塌的离散元模拟及冗余度分析[J]. 岩土力学, 2014, 35(2): 573-583.
[18]CHENG X S, ZHENG G, DIAO Y, et al. Study of the Progressive Collapse Mechanism of Excavations Retained by Cantilever Contiguous Piles[J]. Engineering Failure Analysis, 2017, 71(2): 72-89.
[19]程雪松,郑刚,黄天明, 等. 悬臂排桩支护基坑沿长度方向连续破坏的机理试验研究[J]. 岩土工程学报,2016, 38(9): 1640-1649.
[20] CHENG X S, ZHENG G, DIAO Y, et al. Experimental Study of the Progressive Collapse Mechanism of Excavations Retained by Cantilever Piles[J]. Canadian Geotechnical Journal, 2017, 54(4): 574-587.
[21]郑刚,雷亚伟,程雪松,等. 局部破坏对钢支撑排桩基坑支护体系影响的试验研究[J].2019, 岩土工程学报, 2019,41(8):1390-1399.
[22]GB 50007—2011,建筑地基基础设计规范[S]. 北京: 中国建筑工业出版社,2011.
[23]JGJ 120—2012,建筑基坑支护技术规程[S]. 北京: 中国建筑工业出版社,2012.
[24] TERZAGHI K. Theoretical Soil Mechanics[M]. New York: Wiley, 1943.
[25]BOSSCHER P J, GRAY D H. Soil Arching in Sandy Slopes[J]. Journal of Geotechnical Engineering, 1986, 112(6): 626-645.
[26]ZHENG G, CHENG X S, DIAO Y, et al. Concept and Design Methodology of Redundancy in Braced Excavation and Case Histories[J]. Geotechnical Engineering Journal of the SEAGS & AGSSEA, 2011, 42(3): 13-21.