Mechanism analysis of karst ground collapse caused by the construction of punching piles in Fuwan, Foshan City
-
摘要:
在岩溶区冲孔桩施工处置不当，往往会引起严重的地面塌陷。文章针对佛山富湾冲孔桩施工引发的岩溶地面塌陷事件，在野外调查和测量的基础上，采用钻探和物探等方法，对岩溶地面塌陷地质条件及其形成机理进行研究。研究表明其成因主要有：①基岩砾状灰岩纯度较高，地质构造作用强烈，溶洞极为发育。②第四系底部广泛分布含泥质砂层和残积土层，且砂层分布广、厚度大。③地下水位埋深浅、与地表水力联系强、位于地下水径流通道上，紧靠西江，地下水作用强烈。④受人类工程活动影响，冲孔桩施工振动作用直接引发地面塌陷。其形成过程可归纳为裂隙期→溶洞期→土洞期→塌陷期→群塌期等五个阶段。因此，在岩溶区冲孔桩施工之前，应开展岩溶专项勘查，针对性制定施工方案，在揭穿岩溶通道过程中，特别要加强对岩溶地下水的监测，以保证工程施工和人员安全。
Abstract:In recent years, the increasing intensity of human engineering activities—such as groundwater extraction, drainage for underground engineering, mine drainage, blasting, pile foundation construction and drilling engineering—has led to karst ground collapses. This phenomenon has become an important issue hindering the economic and social development of karst areas. If construction processes in these karst areas are not disposed properly, the punching pile construction commonly used in foundation construction can often cause severe ground collapse disasters. This article examines the karst ground collapse event triggered by the construction of punching piles in Fuwan, Foshan. Through field investigations and measurements, geological conditions contributing to the karst ground collapse were analyzed with drilling and geophysical exploration. A total of 37 boreholes were drilled in the vicinity the collapse, reaching a distance of 1,950 m. In around six of these boreholes (ZK6, ZK13, ZK15, ZK22, ZK18, and ZK31), a comprehensive exploration method was adopted to conduct three-dimensional infinite full-space exploration. This method utilized boreholes for deep underground exploration and high-precision detection of karst geological development within a 40-meter radiu. A total of 46 omnidirectional detection lines were laid out, covering a length of 2,990 m.
Research has shown that the karst ground collapse group on Anhua road in Fuwan is primarily attributed to five factors: (1) The bedrock in this area is composed of high-purity gravel limestone, which is characterized by dense geological structures and numerous karst caves, creating conditions that are conducive to karst ground collapses. (2) The widely distributed muddy sand layers and residual soil layers at the bottom of the Quaternary system provide a favorable material foundation for the development of soil caves. (3) The sand layer is extentively distributed and exhibits a large thickness. Groundwater rescources are abundant and the hydrogeological conditions are complex. (4) The groundwater level is shallow and exhibits a strong hydraulic connection with the surface water. This area is located in a groundwater runoff channel, adjacent to the Xijiang river, and experiences frequent groundwater activities. (5) From the end of 2010 to January 2011, ground collapses occurred due to the vibration generated by punching pile construction.
In addition, the formation of karst ground collapse group on Anhua road in Fuwan can be summarized in five stages: the fissure period, the karst cave period, the soil cave period, the collapse period, and the group collapse period. In the early stage, fissures formed in the bedrock as a result of tectonic action. Subsequently, under the combined influence of factors such as crustal uplift, meteorology, hydrology, structure, and marine transgression and regression, the small joint fissures in the bedrock were gradually eroded and expanded, leading to the formation of karst caves. These karst caves were then gradually developed toward the bedrock surface until the bedrock roof became exposed. This marked the beginning of the development period of soil cave. With the changing seasons and the dynamics of marine transgression and regression, groundwater levels fluctuated. The rise and fall of the groundwater erosion baseline were constantly circulating. When groundwater levels rose, soil that has remained dry for an extended time gradually softened, forming a soft layer. Conversely, as groundwater levels declined, soil lost its buoyancy due to the absence of water, resulting in a sharp increase in hydraulic gradient and an intensified erosive effect of pore water. Under the influence of vacuum negative pressure between pores and the erosion caused by groundwater, small particles within the sand layer were continuely displaced and transported to the underlying karst cave characterized by gravel limestone. Therefore, a soil hole was formed between the gravel limestone and the overlying sandy soil layer, and the hole developed and expanded in all directions. During the periods of collapse and group collapse, the construction of punching piles led to repeated fluctuations in the groundwater level. These fluctuations caused groundwater to flow to the surrounding areas through rock, soil and water, which damaged the original structural performance of the surrounding rock and soil, altered the original mechanical equilibrium limit, and triggered additional karst ground collapses in nearby areas.
In summary, it is advisable to conduct a specialized karst exploration prior to the construction of punching piles in karst areas to identify the distribution characteristics of karst channels. At the same time, targeted construction plans should be developed. If karst channels are exposed during the construction process, it is essential to enhance the monitoring of karst groundwater to ensure the safety of both the engineering project and personnel involved.
-
-
表 1 岩溶地面塌陷地质灾害特征说明表
Table 1. Description of geological hazard characteristics of karst ground collapse
编号 面积/m2 形状 规模/m 深度/m 始发时间 灾害情况 TX1 176 圆形 φ15 1~2 2011/1/13 15:30 3层楼房完全损坏 TX2 706 近圆形 φ30 4~5 2011/1/13 17:30 造成安华路长约75 m的路段损坏 TX3 4 近圆形 φ2 0.5 2011年1月底 
下载: 导出CSV
表 2 研究区岩土体特征表
Table 2. Characteristics of rock and soil mass in the study area
地层 地层代号 层号 揭露厚度/m 土体特征概述 备注 (1)人工填土 Qml (1) 1.00~6.80 填土 隔水层 (2)第四系海陆交互相沉积层 Qmc (2)-1 0.80~3.70 粉质黏土 相对隔水层 (2)-2 1.10~24.40 淤泥和淤泥质土 软土层 (2)-3 0.50~3.10 粉质黏土 (2)-4 2.00~9.90 粉砂 含水层和透水层 (2)-5 1.50~12.90 淤泥质土 软土层 (2)-6 0.90~12.10 粉质黏土 相对隔水层 (2)-7 1.90~18.90 中砂和粗砂 含水层和透水层 (2)-8 0.30~11.90 淤泥质土 软土层 (2)-9 0.80~3.70 粉质黏土 相对隔水层 (2)-10 0.40~4.10 粉细砂 含水层和透水层 (2)-11 1.10~25.90 中砂 含水层和透水层 (2)-12 2.90~11.10 粉细砂 含水层和透水层 (3)第四系残积层 Qedl (3) 2.30~7.70 残坡积土 相对隔水层 (4)早侏罗世金鸡组 J1j (4) 2.10~16.10 微风化灰岩质砾岩 岩溶发育，岩溶含水层
下载: 导出CSV
表 3 研究区地下水特征表
Table 3. Groundwater characteristics in the study area
地下水类型 地下水特征描述 松散岩类孔隙水 主要赋存于第四系海陆交互相沉积层和残积层中，含水介质主要有第(2)-4、(2)-7、(2)-10、(2)-11和(2)-12层砂层，厚度3.10~35.40 m，含水层之间的隔水层主要为第(2)-2、(2)-5、(2)-8层淤泥、淤泥质土，自西南向东北含水层逐渐变厚，砂层之间连通性由西南向东北逐渐变好，且下部砂层大部分直接覆盖于基岩之上，与基岩连通性较好；大部分第四系松散岩类孔隙水上部为潜水、下部为微承压水，与地表水的水力联系较密切，水位埋深1.46~2.68 m，水位高程+2.81~+3.50 m，富水性中等；水化学类型为HCO3-Ca·Na，矿化度0.26 g·L−1 覆盖型碳酸盐岩
类裂隙溶洞水主要赋存于早侏罗世金鸡组（J1j）砾状灰岩的裂隙和溶洞中，由于地下岩溶发育且分布极不均匀，岩溶多呈半充填或无充填状态，仅个别全充填，充填物为黏性土、砂砾等，富水性以中等为主，局部较为丰富，单井涌水量一般150~500 m3·d−1，水位埋深1.30~1.60 m，为承压水，水化学类型以HCO3-Ca为主，矿化度0.81 g·L−1
下载: 导出CSV
表 4 研究区土洞特征表
Table 4. Characteristics of soil caves in the study area
序号 孔号 基岩埋深/m 土洞分布埋深/m 洞高/m 充填情况 洞顶岩性 洞底岩性 1 ZK3 31.50 26.20~27.70 1.50 无 淤泥 中砂 2 ZK5 34.10 31.00~34.10 3.10 无 中砂 灰岩质砾岩 3 ZK17 38.40 32.60~38.40 5.80 无 中砂 灰岩质砾岩 4 ZK23 42.50 39.50~42.50 3.00 无 中砂 灰岩质砾岩 5 ZK25 48.20 44.50~48.20 3.70 无 中砂 灰岩质砾岩 6 ZK30 37.80 37.80~44.90 7.10 半充填 中砂 灰岩质砾岩 7 ZK32 44.50 14.70~17.80 3.10 无 中砂 灰岩质砾岩 8 ZK35 46.80 37.00~46.80 9.80 无 中砂 灰岩质砾岩
下载: 导出CSV
表 5 研究区溶洞特征表
Table 5. Characteristics of karst caves in the study area
序号 孔号 溶洞分布深度/m 洞高/m 洞顶板岩石厚度/m 充填情况 1 ZK6 35.50~40.40 4.90 0.7 上部充填灰褐色粉质黏土，下部含有石英卵石 2 ZK7 49.20~50.80 1.60 0.90 半充填，漏水 3 ZK9 43.00~46.80 3.80 1.00 充填粉质黏土，角砾（风化) 49.00~56.30 7.30 2.20 无充填，漏水 4 ZK10 43.80~45.10 1.30 1.90 充填粉质黏土 5 ZK12 38.20~39.30 1.10 0.60 充填灰褐色粉质黏土，含少量角砾 6 ZK17 38.70~39.80 1.10 0.30 无充填 7 ZK22 41.30~44.40 3.20 0.60 充填黄褐色、红色黏土质，充填物成分复杂，见有全风化之灰岩碎块 46.10~51.60 5.50 1.70 充填黄褐色黏土质，见有灰岩碎块，钻进较快，钻至溶洞底部时伴有漏浆现象 53.20~53.70 0.50 1.60 充填黄褐色黏土质，钻进快 53.90~54.40 0.50 0.20 充填黄褐色黏土质，钻进快 8 ZK22-1 48.90~50.20 1.30 0.70 充填黄褐色黏土质，钻进快 9 ZK23 45.00~47.70 2.70 2.50 充填粉质黏土，灰褐、灰黄色，含少量角砾，漏水 10 ZK24 51.20~53.40 2.20 1.70 无充填，漏水 11 ZK25 51.40~54.80 3.40 3.40 充填粉质黏土，浅褐、灰红色，含角砾 12 ZK32 45.10~47.80 2.70 0.60 充填粗砂，漏水 55.20~56.80 1.60 7.40 半充填，下部充填细中砂，底部0.2 m为灰岩质砾岩 13 ZK33 45.10~49.20 4.10 1.00 半充填，下部充填砂粒，漏水 14 ZK34 46.20~47.00 0.80 0.30 充填，粉质黏土 47.40~48.50 1.10 0.40 无充填，漏水 15 ZK35 46.90~51.30 4.40 0.10 充填少量粉质黏土，漏水 52.10~57.90 5.80 0.80 无充填，于55.2~55.5 m夹有灰岩，漏水 16 ZK36 41.80~46.00 4.20 2.30 半充填，下部充填粉质黏土，漏水
下载: 导出CSV
-
[1] 蒙彦, 黄健民, 贾龙. 基于地下水动力特征监测的岩溶塌陷预警阈值探索:以广州金沙洲岩溶塌陷为例[J]. 中国岩溶, 2018, 37(3):408-414.
MENG Yan, HUANG Jianmin, JIA Long. Early warning threshold of sinkhole collapse based on dynamic characteristics from groundwater monitoring: A case study of Jinshazhou of Guangzhou, China[J]. Carsologica Sinica, 2018, 37(3): 408-414.
[2] Jiang Xiaozhen, Lei Mingtang, Gao Yongli, Guan Zhende. Characterization of karst collapse hazard based on groundwater fluctuations in Qingyun village, Guigang, Guangxi, China[C]//National Cave and Karst Research Institute Symposium, 2013: 321-326.
[3] 冯佐海, 陈南春, 韦继武. 桂林市柘木岩溶塌陷成因及其分布的基本特征[J]. 中国地质灾害与防治学报, 1998, 9(3):85-89, 106.
FENG Zuohai, CHEN Nanchun, WEI Jiwu. Security prediction of railway in the land subsidence area[J]. The Chinese Journal of Geological Hazard and Control, 1998, 9(3): 85-89, 106.
[4] 马骁, 蒋小珍, 雷明堂, 李亚军, 贾龙. 桩基施工诱发岩溶塌陷的机理模式及防控措施[J]. 地下空间与工程学报, 2023, 19(2):691-700.
MA Xiao, JIANG Xiaozhen, LEI Mingtang, LI Yajun, JIA Long. Mechanism model and prevention and control measures of karst collapse induced by pile foundation construction[J]. Chinese Journal of Underground Space and Engineering, 2023, 19(2): 691-700.
[5] 陈贻祥, 潘科. 综合物探方法在岩溶塌陷探测中的应用分析[J]. 人民长江, 2012, 43(Suppl.2):9-11, 32.
[6] 李慧娟, 陈梦源, 梁川, 涂婧. 武汉市长江一级阶地钻探施工诱发岩溶塌陷的形成机制分析[J]. 资源环境与工程, 2022, 36(2):193-197.
LI Huijuan, CHEN Mengyuan, LIANG Chuan, TU Jing. Formation mechanism analysis of karst collapse caused by drilling in first terrace of Yangtze River in Wuhan City[J]. Resources Environment & Engineering, 2022, 36(2): 193-197.
[7] 贾龙, 蒙彦, 潘宗源, 殷仁朝. 钻孔雷达反射成像在岩溶发育场地探测中的应用[J]. 中国岩溶, 2019, 38(1):124-129.
JIA Long, MENG Yan, PAN Zongyuan, YIN Renchao. Study on application of borehole radar reflection imaging in the detection of karst area[J]. Carsologica Sinica, 2019, 38(1): 124-129.
[8] 辛然. 临桂道光村岩溶塌陷调查方法及影响因素, 成因模拟分析[D]. 桂林:桂林理工大学, 2013
XIN Ran. Investigation methods, influencing factors and cause simulation analysis for the karst collapse in Daoguang village, Lingui county[D]. Guilin: Guilin University of Technology, 2013
[9] Lei Mingtang, Gao Yongli, Jiang Xiaozhen, Guan Zhende. Mechanism analysis of sinkhole formation at Maohe village, Liuzhou city, Guangxi Province, China[J]. Environmental Earth Sciences, 2016, 75(7): 1-11.
[10] 熊志涛, 刘鹏瑞, 杨涛, 邵勇. 江夏法泗岩溶塌陷区冲孔桩施工引发岩溶塌陷的成因机理[J]. 中国岩溶, 2018, 37(1):120-129.
XIONG Zhitao, LIU Pengrui, YANG Tao, SHAO Yong. Mechanism of karst collapse caused by punching pile construction in Jiangxia Fasi karst collapse area[J]. Carsologica Sinica, 2018, 37(1): 120-129.
[11] Jiang Fuwei, Dai Jianling, Lei Mingtang, Qin Youqiang, Jiang Xiaozhen, Meng Yan. Experimental study on the critical triggering condition of soil failure in subsidence sinkholes[J]. Environmental Earth Sciences, 2015, 74(1): 693-701. doi: 10.1007/s12665-015-4074-7
[12] 张宗胜. 佛山黄岐海北片区岩溶地面塌陷地质灾害成因与趋势分析[J]. 中国岩溶, 2022, 41(6):880-894.
ZHANG Zongsheng. Origin and trend analysis of karst collapse in Huangqi and Haibei communities, Foshan City[J]. Carsologica Sinica, 2022, 41(6): 880-894.
[13] 韩庆定, 罗锡宜, 易守勇, 邹杰. 广东佛山市高明区三洲盆地岩溶塌陷发育特征与时空分布规律[J]. 中国地质灾害与防治学报, 2021, 32(3):131-139.
HAN Qingding, LUO Xiyi, YI Shouyong, ZOU Jie. Characteristics and spatial-temporal distribution of karst collapse in Sanzhou basin, Gaoming district, Foshan City, Guangdong Province[J]. Chinese Journal of Geological Hazards and Prevention, 2021, 32(3): 131-139.
-
图(8)
表(5)
计量
- 文章访问数: 168
- PDF下载数: 11
- 施引文献: 0