Measurement and mechanism of influences of rainfall on supporting structures of foundation pits in soft soils

LIU Chang; JI Fan-fan; ZHENG Gang; LIU Tao; LIU Yong-chao

doi:10.11779/CJGE202003006

Volume 42 Issue 3

Turn off MathJax

Article Contents

Abstract

References

Chinese Journal of Geotechnical Engineering > 2020 > 42(3): 447-456. > DOI: 10.11779/CJGE202003006

LIU Chang, JI Fan-fan, ZHENG Gang, LIU Tao, LIU Yong-chao. Measurement and mechanism of influences of rainfall on supporting structures of foundation pits in soft soils[J]. Chinese Journal of Geotechnical Engineering, 2020, 42(3): 447-456. DOI: 10.11779/CJGE202003006

Citation:

PDF (1356 KB)

Measurement and mechanism of influences of rainfall on supporting structures of foundation pits in soft soils

LIU Chang^{1, 2,},
JI Fan-fan¹,
ZHENG Gang^{1, 2},
LIU Tao^{1, 4},
LIU Yong-chao³

1.
School of Civil Engineering, Tianjin University, Tianjin 300072, China
2.
Key Laboratory of Coast Civil Structure Safety, Ministry of Education, Tianjin 300072, China
3.
Tianjin Pile Foundation Technology Engineering Center, Tianjin 300301, China
4.
Beijing Longhu Zhongbai Real Estate Co., Ltd., Beijing 100020, China

More Information

Received Date: December 23, 2018
Available Online: December 07, 2022

Graphical Abstract

Abstract

Abstract

Rainfall is usually easy to cause sliding and instability of soil slopes. At the same time, it also has a great influence on foundation pits, especially for those in soft soils. In the absence of other construction, after three days of rainfall of 247 mm deep, the horizontal displacement of supporting structures of a foundation pit in Tianjin increases by 13.75 mm. Therefore, it is of great significance to study the mechanism of deformation induced by rainfall of foundation pits in soft soils. Firstly, the experiments on the influences of rainfall on relevant model are conducted by using Plaxis2D. The influence mechanism of rainfall on the deformation of supporting structures of the foundation pit in soft soils is analyzed. The influences of intensity, duration and amount of rainfall on the deformation of supporting structures are analyzed, and the sensitivities of the excavation depth, the initial displacement of pile top, the form of supporting structures to rainfall are studied. The main factors affecting the deformation of supporting structures are the increase of the residual soils outside the pit, the softening of the soils in the pit and the fluid-solid coupling. The amount of rainfall is a factor to have a large influence on the deformation of the supporting structures of the foundation pit. The displacement increment of the supporting structures caused by rainfall is most affected by their initial displacement, while the depth of foundation excavation has small influences on their deformation increment under the same rainfall conditions.
- rainfall,
- soft soil,
- foundation pit,
- supporting structure

FullText(HTML)

References (17)

References

[1]	张华庆, 谭佳佳, 左殿军. 降雨入渗对软土岸坡稳定性影响研究[J]. 水运工程, 2014(4): 148-153. https://www.cnki.com.cn/Article/CJFDTOTAL-SYGC201404034.htm ZHANG Hua-qing, TAN Jia-jia, ZUO Dian-jun. Stability study of unsaturated soft soil slopes under rainfall infiltration[J]. Port and Waterway Engineering, 2014(4): 148-153. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-SYGC201404034.htm
[2]	李振嵩. 降雨条件下非饱和土边坡的稳定性分析[D]. 广州: 中山大学, 2007. LI Zhen-song. Stability Analysis of Unsaturated Soil Slopes Under the Conditions of Rainfall[D]. Guangzhou: Sun Yat-Sen University, 2007. (in Chinese)
[3]	孔郁斐, 周梦佳, 宋二祥, 等. 利用PLAXIS软件计算考虑降雨的边坡稳定性[J]. 水利水运工程学报, 2014(3): 70-76. https://www.cnki.com.cn/Article/CJFDTOTAL-SLSY201403011.htm KONG Yu-wen, ZHOU Meng-jia, KONG Er-xiang, et al. Caculation of the slope using Plaxis software under the conditions of rainfall[J]. Hydro-Science and Engineering, 2014(3): 70-76. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-SLSY201403011.htm
[4]	刘子振. 持续降雨入渗非饱和黏土边坡失稳机理及其应用研究[D]. 兰州: 兰州大学, 2014. LIU Zi-zhen. Instability Mechanism and Application Analysis of Partially Saturated Clay Slope Under Sustained Rainfall Infiltration[D]. Lanzhou: Lanzhou University, 2014. (in Chinese)
[5]	石振明, 沈丹祎, 彭铭, 等. 考虑多层非饱和土降雨入渗的边坡稳定性分析[J]. 水利学报, 2016, 47(8): 977-985. https://www.cnki.com.cn/Article/CJFDTOTAL-SLXB201608002.htm SHI Zhen-ming, SHEN Dan-yi, PENG Ming, et al. Slope stability analysis by considering rainfall infiltration in multi-layered unsaturated soils[J]. Journal of Hydraulic Engineering, 2016, 47(8): 977-985. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-SLXB201608002.htm
[6]	王玉军. 降雨入渗对黏土边坡的影响分析[D]. 成都: 西南石油大学, 2016. WANG Yu-jun. Stability Analysis of Clay Slope Under Rainfall Infiltration[D]. Chengdu: Southwest Petroleum University, 2016. (in Chinese)
[7]	徐全, 谭晓慧, 沈梦芬. 降雨入渗条件下土质边坡的稳定性分析[J]. 岩土工程学报, 2012, 34(增刊): 254-259. https://www.cnki.com.cn/Article/CJFDTOTAL-YTGC2012S1053.htm XU Quan, TAN Xiao-hui, SHEN Meng-fen. Stability analysis of soil slopes under rainfall infiltration[J]. Chinese Journal of Geotechnical Engineering, 2012, 34(S0): 254-259. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-YTGC2012S1053.htm
[8]	彭立新. 降雨入渗对地铁基坑边坡变形影响分析[D]. 武汉: 华中科技大学, 2011. PENG Li-xin. Analysis of Rainfall Infiltration on Deformation of Subway Excavation Slope[D]. Wuhan: Huazhong University of Science and Technology, 2011. (in Chinese)
[9]	李炎隆, 陈波, 马成成, 等. 基于ABAQUS的降雨入渗条件下基坑边坡稳定性分析[J]. 应用力学学报, 2017, 34(1): 155-161. https://www.cnki.com.cn/Article/CJFDTOTAL-YYLX201701026.htm LI Yan-long, CHEN Bo, MA Cheng-cheng, et al. Analysis of excavation slope under rainfall infiltration basing on ABAQUS[J]. Chinese Journal of Applied Mechanics, 2017, 34(1): 155-161. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-YYLX201701026.htm
[10]	邱海兵. 降雨入渗对非饱和土基坑围护结构稳定性影响的研究[D]. 西安: 西安建筑科技大学, 2013. QIU Hai-bing. Study of rain infiltration on stability of unsaturated pit supporting structure[D]. Xi'an: Xi'an University of Architecture and Technology, 2013. (in Chinese)
[11]	崔凤展. 强降雨作用下土质深基坑稳定性及其控制技术研究[D]. 北京: 中国矿业大学(北京), 2016. CUI Feng-zhan. Study on the Stability and Controlling Technology of Soil Deep Foundation Pit under Strong Rainfall[D]. Beijing: China University of Mining & Technology, 2016. (in Chinese)
[12]	周根郯. 成都膨胀土基坑边坡降雨条件与支护结构内力关系的数值模拟研究[D]. 成都: 西南交通大学, 2016. ZHOU Gen-tan. The Numerical Emulation Study on the Relationship between the Rainfall Conditions and the Internal Force of Retaining Structure of Expansive Soil Foundation Pit in Chengdu[D]. Chengdu: Southwest Jiaotong University, 2016. (in Chinese)
[13]	MORGENSTERN N R, PRICE V. The analysis of the stability general slip surface[J]. Géotechnique, 1965, 15(1): 79-93.
[14]	覃小华, 刘东升, 宋强辉, 等. 降雨条件下一维土柱垂直入渗模型试验研究及其渗透系数求解[J]. 岩石力学与工程学报, 2017, 36(2): 475-484. https://www.cnki.com.cn/Article/CJFDTOTAL-YSLX201702019.htm QIN Xiao-hua, LIU Dong-sheng, SONG Qiang-hui, et al. Experimental study on one-dimensional vertical infiltration in soil column under rainfall and the derivation of permeability coefficient[J]. Chinese Journal of Rock Mechanics and Engineering, 2017, 36(2): 475-484. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-YSLX201702019.htm
[15]	陈文苏. 软土蠕变沉降的数值模拟[D]. 天津: 天津大学, 2004. CHEN Wen-su. Numerical Simulation of Creep Settlement of Soft Soil[D]. Tianjin: Tianjin University, 2004. (in Chinese)
[16]	FREDLUND D G. Appropriate concepts and technology for unsaturated soils[J]. Candan Geotechnique Journal, 1979, 16: 121-129.
[17]	GRIFFITHS D V, LANE P A. Slope stability analysis by finite elements[J]. Géotechnique, 1999, 3(49): 387-403.

[1]	LI Li, LIU Zi-ru. Method for lateral forces in stability analysis of concave slopes in plan view[J]. Chinese Journal of Geotechnical Engineering, 2018, 40(S2): 137-141. DOI: 10.11779/CJGE2018S2028
[2]	QIN Zhong-guo, ZHANG Xiang-yang. New method for slope stability analysis[J]. Chinese Journal of Geotechnical Engineering, 2016, 38(5): 946-951. DOI: 10.11779/CJGE201605022
[3]	CAO Ping, LIU Di-xu. Application of improved CSMR method to opencast mining slopes[J]. Chinese Journal of Geotechnical Engineering, 2015, 37(8): 1544-1548. DOI: 10.11779/CJGE201508027
[4]	LEI Guo-hui, ZHENG Qiang. Issues on concepts of effective stress and seepage force arising from anatomizing Swedish slice method[J]. Chinese Journal of Geotechnical Engineering, 2012, 34(4): 667-676.
[5]	WANG Hongbo, SHAO Longtan, XIONG Baolin. Improved method to determine parameters n and hs of a hypoplastic constitutive model[J]. Chinese Journal of Geotechnical Engineering, 2006, 28(9): 1173-1176.
[6]	ZHANG Qianfei, WU Zhongru. The improved cut-off negative pressure method for unsteady seepage flow with free surface[J]. Chinese Journal of Geotechnical Engineering, 2005, 27(1): 48-54.
[7]	SHI Weimin, ZHENG Yingren, TANG Boming, ZHANG Luyu. Accuracy and application range of Imbalance Thrust Force Method for slope stability analysis[J]. Chinese Journal of Geotechnical Engineering, 2004, 26(3): 313-317.
[8]	WANG Jianfeng. An analytical method of the stabilizing force of piles for landslide control using Janbu’s generalized procedure of slices[J]. Chinese Journal of Geotechnical Engineering, 2003, 25(4): 455-458.
[9]	Wang Zhiyin, Li Yunpeng. Some improvements in the numerical manifold method[J]. Chinese Journal of Geotechnical Engineering, 1998, 20(6): 36-39.
[10]	Zhang Xiong. lmProved Slice Method for Slope Stability Analysis[J]. Chinese Journal of Geotechnical Engineering, 1994, 16(3): 84-92.