Analysis of collapsible deformation and vertical soil pressure action of thick loess foundation
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摘要:
黄土地基浸水后的湿陷变形对黄土地区的工程建设具有重大影响，但以往研究对深厚黄土地基土浸水过程的湿陷特性及其土压力变化规律研究不够充分。以中兰铁路兰州新区南站某场地为例，开展现场浸水试验，对深厚湿陷性黄土场地的地表位移及地基深层湿陷变形进行监测，同时埋设土压力盒，对浸水湿陷过程中地基土的竖向土压力的变化规律进行分析。研究结果表明：（1）该深厚黄土场地最大湿陷下沉量在150 cm左右，浸水范围10 m以外的地表基本不发生湿陷下沉；（2）根据深层沉降测试结果可知，0~15 m深度范围内该黄土地基为强湿陷土层，湿陷量达到120 cm左右，占整个场地湿陷量的80%以上，24 m深度以下地基土不发生湿陷，为非自重湿陷土层；（3）根据土压力监测分析，15 m深度以上的地基土浸水后土体结构完全溃散，测试得到的土压力即为上覆土体的自重压力，15 m深度以下的土体浸水后虽产生一定的湿陷下沉，但土体结构未发生完全破坏，对上覆自重荷载仍具有一定的支撑作用。研究结论可为中兰铁路后期工程及兰州新区的建设提供一定的技术参考。
Abstract:The collapsible deformation characteristics of loess foundation after flooding are of great significance in the engineering construction in loess regions. However, previous studies of the collapsible characteristics of deep loess foundation soil during the process of flooding and the variation law of soil pressure are not perfect. In this paper, a site in the South Station of Lanzhou New District of the Zhongwei-Lanzhou Railway is taken as an example and a field immersion test is carried out at the site to monitor the surface displacement and deep wet sink deformation of the foundation of the deep wet sink loess site. At the same time, soil pressure boxes are buried to analyze the change law of vertical soil pressure of the foundation soil during the immersion wet sink process. The research results show that (1) the maximum wet sink of the deep loess site is around 150 cm, and wet sink basically does not occur at the ground surface outside 10 m of the water immersion range. (2) According to the deep settlement test results, it can be seen that the loess foundation 0−15 m deep is the range of the strong wet sink soil layer, and the wet sink amount reaches about 120 cm, accounting for more than 80% of the wet sink amount of the whole site. Wet sink does not occur in the foundation soil 24 m deep and it is a non-self-weight wet sink soil layer. (3) According to the soil pressure monitoring analysis, it is obtained that the soil structure within 15 m in depth is completely collapsed after water immersion, and the soil pressure obtained from the test is the self-weight pressure of the overlying soil. A certain amount of wet subsidence after water immersion occurs at a depth of 15 m or less, but the soil structure is not completely destroyed, and it still has a certain support effect on the overlying self-weight load. The results of this study can provide some technical references for the later construction of the Zhongwei-Lanzhou Railway and the Lanzhou New District.
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表 1 试验场地地层岩性表
Table 1. Lithology of the test site
地层名称 分布深度/m 地层岩性 岩性特征 砂质黄土
（
）0~3.5 第四系全新统
（Q4）浅黄色，稍湿，稍密，
以砂质黄土为主砂质黄土
（
）1.5~45 第四系上更新统
（Q3）浅黄色，稍湿，稍密，土质
均匀，可见针孔状大孔隙和
虫孔，具湿陷性
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表 2 土体基本物理指标
Table 2. Basic physical properties of soil
土样 最优含水率/% 最大干密度/（g·cm−3） 液限/% 塑限/% 土粒比重 粉质黏土 13.2 1.89 29.27 16.68 2.71
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[1] 董林,王兰民,夏坤,等. 原状黄土遇水及饱和后软化特征研究[J]. 水文地质工程地质,2016,43(3):148 − 152. [DONG Lin, WANG Lanmin, XIA Kun, et al. A study of soften characteristics of wet and saturated loess[J]. Hydrogeology & Engineering Geology,2016,43(3):148 − 152. (in Chinese with English abstract)
DONG Lin, WANG Lanmin, XIA Kun, et al. A study of soften characteristics of wet and saturated loess [J]. Hydrogeology & Engineering Geology, 2016,43(3):148-152. (in Chinese with English abstract)
[2] 孙萍萍,张茂省,江睿君,等. 降雨诱发浅层黄土滑坡变形破坏机制[J]. 地质通报,2021,40(10):1617 − 1625. [SUN Pingping, ZHANG Maosheng, JIANG Ruijun, et al. Deformation and failure mechanism of rainfall-induced shallow loess landslide[J]. Geological Bulletin of China,2021,40(10):1617 − 1625. (in Chinese with English abstract)
SUN Pingping, ZHANG Maosheng, JIANG Ruijun, et al. Deformation and failure mechanism of rainfall-induced shallow loess landslide[J]. Geological Bulletin of China, ,2021,40(10):1617-1625. (in Chinese with English abstract)
[3] 谢定义. 试论我国黄土力学研究中的若干新趋向[J]. 岩土工程学报,2001(1):3 − 13. [XIE Dingyi. Exploration of some new tendencies in research of loess soil mechanics[J]. Chinese Journal of Geotechnical Engineering,2001(1):3 − 13. (in Chinese with English abstract) doi: 10.3321/j.issn:1000-4548.2001.01.002
XIE Dingyi. Exploration of some new tendencies in research of loess soil mechanics[J]. Chinese Journal of Geotechnical Engineering, 2001(1): 3-13. (in Chinese with English abstract) doi: 10.3321/j.issn:1000-4548.2001.01.002
[4] 连杰明. 挤密法处理湿陷性黄土地基主要设计指标探讨[J]. 水文地质工程地质,2012,39(6):87 − 92. [LIAN Jieming. Investigation of main design index of collapsible loess foundation treated with compaction pile[J]. Hydrogeology & Engineering Geology,2012,39(6):87 − 92. (in Chinese with English abstract)
LIAN Jieming. Investigation of main design index of collapsible loess foundation treated with compaction pile[J]. Hydrogeology & Engineering Geology, 2012, 39(6): 87-92. (in Chinese with English abstract)
[5] 王治军, 潘俊义, 马闫, 等. 董志塬大厚度自重湿陷性黄土场地浸水试验研究[J]. 水文地质工程地质,2016,43(2):75 − 82. [WANG Zhijun, PAN Junyi, MA Yan, et al. Immersion test on the self-weight collapsible loess in the Dongzhiyuan area[J]. Hydrogeology & Engineering Geology,2016,43(2):75 − 82. (in Chinese with English abstract)
WANG Zhijun, PAN Junyi, MA Yan, et al. Immersion test on the self-weight collapsible loess in the Dongzhiyuan area[J]. Hydrogeology & Engineering Geology, 2016, 43(2): 75-82. (in Chinese with English abstract)
[6] 黄雪峰, 杨校辉. 湿陷性黄土现场浸水试验研究进展[J]. 岩土力学,2013,34(增刊 2):222 − 228. [HUANG Xuefeng, YANG Xiaohui. A study progress on in-situ soaking test on collapsible loess[J]. Rock and Soil Mechanics,2013,34(Sup 2):222 − 228. (in Chinese with English abstract)
HUANG Xuefeng, YANG Xiaohui. A study progress on in-situ soaking test on collapsible loess[J]. Rock and Soil Mechanics, 2013, 34(Sup2): 222-228. (in Chinese with English abstract)
[7] 黄雪峰, 陈正汉, 哈双, 等. 大厚度自重湿陷性黄土场地湿陷变形特征的大型现场浸水试验研究[J]. 岩土工程学报,2006(3):382 − 389. [HUANG Xuefeng, CHEN Zhenghan, HA Shuang, et al. Large area field immersion tests on characteristics of deformation of self weight collapse loess under overburden pressure[J]. Chinese Journal of Geotechnical Engineering,2006(3):382 − 389. (in Chinese with English abstract) doi: 10.3321/j.issn:1000-4548.2006.03.019
HUANG Xuefeng, CHEN Zhenghan, HA Shuang, et al. Large area field immersion tests on characteristics of deformation of self weight collapse loess under overburden pressure[J]. Chinese Journal of Geotechnical Engineering, 2006(3): 382-389. (in Chinese with English abstract) doi: 10.3321/j.issn:1000-4548.2006.03.019
[8] 杨校辉, 黄雪峰, 朱彦鹏, 等. 大厚度自重湿陷性黄土地基处理深度和湿陷性评价试验研究[J]. 岩石力学与工程学报,2014,33(5):1063 − 1074. [YANG Xiaohui, HUANG Xuefeng, ZHU Yanpeng, et al. Experimental study on collapsibility evaluation and treatment depths of collapsible loess upon self weight with thick depth[J]. Chinese Journal of Rock Mechanics and Engineering,2014,33(5):1063 − 1074. (in Chinese with English abstract)
YANG Xiaohui, HUANG Xuefeng, ZHU Yanpeng, et al. Experimental study on collapsibility evaluation and treatment depths of collapsible loess upon self weight with thick depth[J]. Chinese Journal of Rock Mechanics and Engineering, 2014, 33(5): 1063-1074. (in Chinese with English abstract)
[9] 邵生俊, 李骏, 李国良, 等. 大厚度自重湿陷黄土湿陷变形评价方法的研究[J]. 岩土工程学报,2015,37(6):965 − 978. [SHAO Shengjun, LI Jun, LI Guoliang, et al. Evaluation method for self-weight collapsible deformation of large thickness loess foundation[J]. Chinese Journal of Geotechnical Engineering,2015,37(6):965 − 978. (in Chinese with English abstract) doi: 10.11779/CJGE201506001
SHAO Shengjun, LI Jun, LI Guoliang, et al. Evaluation method for self-weight collapsible deformation of large thickness loess foundation[J]. Chinese Journal of Geotechnical Engineering, 2015, 37(6): 965-978. (in Chinese with English abstract) doi: 10.11779/CJGE201506001
[10] LI J, SHAO S J, SHAO S. Collapsible characteristics of loess tunnel site and their effects on tunnel structure[J]. Tunneling and Underground Space Technology,2019,83:509 − 519. doi: 10.1016/j.tust.2018.08.035
[11] 吴爽,高玉广,赵权利,等. 黄土地场自重湿陷量实测值与计算值差异的原因分析[J]. 西北地质,2019,52(4):263 − 269. [WU Shuang, GAO Yuguang, ZHAO Quanli, et al. Reason analysis for the difference between measured and calculated self-weight collapsibility of the loess[J]. Northwestern Geology,2019,52(4):263 − 269. (in Chinese with English abstract)
WU Shuang, GAO Yuguang, ZHAO Quanli, et al. Reason analysis for the difference between measured and calculated self-weight collapsibility of the loess[J]. Northwestern Geology, 2019, 52(4):263-269. (in Chinese with English abstract)
[12] 张晓宇,毕焕军,曹峰,等. 渗流作用下黄土含水率变化特征及对隧道工程的影响[J]. 水文地质工程地质,2021,48(4):41 − 47. [ZHANG Xiaoyu, BI Huanjun, CAO Feng, et al. Characteristics of moisture content variation of loess under seepage and its influence on tunnel engineering[J]. Hydrogeology & Engineering Geology,2021,48(4):41 − 47. (in Chinese with English abstract)
ZHANG Xiaoyu, BI Huanjun, CAO Feng, et al. Characteristics of moisture content variation of loess under seepage and its influence on tunnel engineering [J]. Hydrogeology & Engineering Geology, 2021,48(4):41-47. (in Chinese with English abstract)
[13] 王小军, 米维军, 熊治文, 等. 郑西客运专线黄土地基湿陷性现场浸水试验研究[J]. 铁道学报,2012,34(1):83 − 90. [WANG Xiaojun, MI Weijun, XIONG Zhiwen, et al. Water immersion field tests of collapsibility of loess foundation of Zhengzhou—Xi’an passenger dedicated line[J]. Journal of the China Railway Society,2012,34(1):83 − 90. (in Chinese with English abstract) doi: 10.3969/j.issn.1001-8360.2012.01.015
WANG Xiaojun, MI Weijun, XIONG Zhiwen, et al. Water immersion field tests of collapsibility of loess foundation of Zhengzhou-Xi'an passenger dedicated line[J]. Journal of the China Railway Society, 2012, 34(1): 83-90. (in Chinese with English abstract) doi: 10.3969/j.issn.1001-8360.2012.01.015
[14] 武小鹏, 王兰民, 房建宏, 等. 原状黄土地基渗水特性及其与自重湿陷的关系研究[J]. 岩土工程学报,2018,40(6):1002 − 1010. [WU Xiaopeng, WANG Lanmin, FANG Jianhong, et al. Seepage characteristics and their relationship with self-weight collapse of intact loess ground[J]. Chinese Journal of Geotechnical Engineering,2018,40(6):1002 − 1010. (in Chinese with English abstract) doi: 10.11779/CJGE201806005
WU Xiaopeng, WANG Lanmin, FANG Jianhong, et al. Seepage characteristics and their relationship with self-weight collapse of intact loess ground[J]. Chinese Journal of Geotechnical Engineering, 2018, 40(6): 1002-1010. (in Chinese with English abstract) doi: 10.11779/CJGE201806005
[15] 姚志华, 黄雪峰, 陈正汉, 等. 兰州地区大厚度自重湿陷性黄土场地浸水试验综合观测研究[J]. 岩土工程学报,2012,34(1):65 − 74. [YAO Zhihua, HUANG Xuefeng, CHEN Zhenghan, et al. Comprehensive soaking tests on self-weight collapse loess with heavy section in Lanzhou region[J]. Chinese Journal of Geotechnical Engineering,2012,34(1):65 − 74. (in Chinese with English abstract)
YAO Zhihua, HUANG Xuefeng, CHEN Zhenghan, et al. Comprehensive soaking tests on self-weight collapse loess with heavy section in Lanzhou region[J]. Chinese Journal of Geotechnical Engineering, 2012, 34(1): 65-74. (in Chinese with English abstract)
[16] 黄雪峰, 李佳, 崔红, 等. 非饱和原状黄土垂直高边坡潜在土压力原位测试试验研究[J]. 岩土工程学报,2010,32(4):500 − 506. [HUANG Xuefeng, LI Jia, CUI Hong, et al. Distribution characteristics of earth pressure for unsaturated intact loess[J]. Chinese Journal of Geotechnical Engineering,2010,32(4):500 − 506. (in Chinese with English abstract)
HUANG Xuefeng, LI Jia, CUI Hong, et al. Distribution characteristics of earth pressure for unsaturated intact loess[J]. Chinese Journal of Geotechnical Engineering, 2010, 32(4): 500-506. (in Chinese with English abstract)
[17] 黄雪峰, 李佳. 渗透对非饱和原状黄土高边坡土压力和水平位移影响的试验研究[J]. 岩石力学与工程学报,2011,30(3):635 − 642. [HUANG Xuefeng, LI Jia. Test study on influence of immersion on earth pressure and horizontal displacement of high slope of unsaturated intact loess[J]. Chinese Journal of Rock Mechanics and Engineering,2011,30(3):635 − 642. (in Chinese with English abstract)
HUANG Xuefeng, LI Jia. Test study on influence of immersion on earth pressure and horizontal displacement of high slope of unsaturated intact loess[J]. Chinese Journal of Rock Mechanics and Engineering, 2011, 30(3): 635-642. (in Chinese with English abstract)
[18] 罗奇斌, 王家鼎, 康卫东, 等. 湿陷性黄土试坑浸水试验中土压力变化特征分析[J]. 水文地质工程地质,2012,39(4):88 − 91. [LUO Qibin, WANG Jiading, KANG Weidong, et al. Analyses of pressure variation characteristics in the immersion test of collapsible loess[J]. Hydrogeology & Engineering Geology,2012,39(4):88 − 91. (in Chinese with English abstract)
LUO Qibin, WANG Jiading, KANG Weidong, et al. Analyses of pressure variation characteristics in the immersion test of collapsible loess[J]. Hydrogeology & Engineering Geology, 2012, 39(4): 88-91. (in Chinese with English abstract)
[19] 李加贵, 陈正汉, 黄雪峰, 等. 原状非饱和Q3黄土的土压力原位测试和强度特性研究[J]. 岩土力学,2010,31(2):433 − 440. [LI Jiagui, CHEN Zhenghan, HUANG Xuefeng, et al. In-site test on earth pressure and saturating collapse test for unsaturated loess Q3 on high slope[J]. Rock and Soil Mechanics,2010,31(2):433 − 440. (in Chinese with English abstract) doi: 10.3969/j.issn.1000-7598.2010.02.018
LI Jiagui, CHEN Zhenghan, HUANG Xuefeng, et al. In-site test on earth pressure and saturating collapse test for unsaturated loess Q3 on high slope[J]. Rock and Soil Mechanics, 2010, 31(2): 433-440. (in Chinese with English abstract) doi: 10.3969/j.issn.1000-7598.2010.02.018
[20] 金松丽, 赵卫全, 张爱军, 等. 原状黄土增湿过程中的静止土压力系数变化规律试验研究[J]. 工程科学与技术,2017,49(5):63 − 70. [JIN Songli, ZHAO Weiquan, ZHANG Aijun, et al. Experimental study of variation rules of the coefficient of earth pressure at rest during wetting for original loess[J]. Advanced Engineering Sciences,2017,49(5):63 − 70. (in Chinese with English abstract)
JIN Songli, ZHAO Weiquan, ZHANG Aijun, et al. Experimental study of variation rules of the coefficient of earth pressure at rest during wetting for original loess[J]. Advanced Engineering Sciences, 2017, 49(5): 63-70. (in Chinese with English abstract)
[21] 孙萍,王刚,李荣建,等. 降雨条件下黄土边坡现场试验研究[J]. 工程地质学报,2019,27(2):466 − 476. [SUN Ping, WANG Gang, LI Rongjian, et al. Study on field test of loess slope under the artificial rainfall condition[J]. Journal of Engineering Geology,2019,27(2):466 − 476. (in Chinese with English abstract)
SUN Ping, WANG Gang, LI Rongjian, et al. Study on field test of loess slope under the artificial rainfall condition[J]. Journal of Engineering Geology,2019,27(2):466-476. (in Chinese with English abstract)
[22] 中华人民共和国住房和城乡建设部. 湿陷性黄土地区建筑规范: GB 50025—2018[S]. 2019.
Ministry of Housing and Urban-Rural Development of the People’s Republic of China. Code for building construction in collapsible loess regions: GB 50025—2018[S]. 2019. （in Chinese）
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