沧州地区土层固结特征与地面沉降临界水位研究  

A study of the critical groundwater level related to soil consolidation characteristics of land subsidence in Cangzhou

作　　者：王云龙 陈晔[3] 郭海朋 孟静 王海刚[1,2] 臧西胜[1,2] 朱菊艳 WANG Yunlong;CHEN Ye;GUO Haipeng;MENG Jing;WANG Haigang;ZANG Xisheng;ZHU Juyan(Hebei Cangzhou Groundwater and Land Subsidence National Observation and Research Station,Cangzhou,Hebei 061000,China;China Institute of Geo-Environment Monitoring,Beijing 100081,China;School of Water Resources and Environment,China University of Geosciences(Beijing),Beijing 100083,China;Institute of Geomechanics,Chinese Academy of Geological Sciences,Beijing 100081,China)

机构地区：[1]河北沧州平原区地下水与地面沉降国家野外科学观测研究站,河北沧州061000 [2]中国地质环境监测院,北京100081 [3]中国地质大学(北京)水资源与环境学院,北京100083 [4]中国地质科学院地质力学研究所,北京100081

出　　处：《水文地质工程地质》2023年第4期185-192,共8页Hydrogeology & Engineering Geology

基　　金：国家自然科学基金项目(41877294);中国地质调查局地质调查项目(DD202304039,DD20190679,DD20160235)。

摘　　要：沧州市长期以来面临严重的地面沉降问题,在控制沉降发展的前提下,为合理利用地下水资源,需要确立开采水位埋深警戒线。针对地面沉降综合防治如何确定临界水位这一科学问题,以沧州3个典型沉降区土样为研究对象,分析了地层固结特征,通过关联地层厚度的方式改进了以先期固结压力求解临界水位的方法,结合多年来地面沉降与地下水水位监测数据,对沧州市临界水位进行了综合定量评估。研究表明:沧州地区0~150 m以内多为正常固结或欠固结土,150 m以下普遍为超固结土,非弹性释水变形是影响该地区地面沉降速率变化的重要因素。运用改进后的方法计算出沧州市区、肃宁县及东光县的临界水位埋深分别为66.8,67.5,67.8 m。综合分析沧州市区累计地面沉降与地下水水位变化资料,得出两者之间的指数函数关系,并以沉降速率为指标,求得65~70 m为沧州市区临界水位区间范围。在验证了两种方法计算结果一致性的基础上,最终将65 m作为沧州市区采取地面沉降防控措施的参考临界水位,为地方政府制定合理的地下水开采方案提供可靠依据。Land subsidence has become a serious issue in Cangzhou for a long time.In order to make reasonable use of groundwater resources,it is necessary to establish a warning groundwater level under the premise of controlling the development of land subsidence.How to quantitatively determine the critical gorundwater level(CWL)for comprehensive control of land subsidence?In allusion to this scientific problem,this paper takes the soil samples of three typical settlement areas in Cangzhou as the research object,and analyzes the formation consolidation characteristics.By correlating the stratum thickness,we improve the method of calculating the CWL with the previous consolidation pressure.Based on the monitoring data of land subsidence and groundwater level in Cangzhou for many years,the comprehensive quantitative evaluation of the CWL in Cangzhou are carried out.The results show that the soil within a depth ranging from 0 to 150 m in Cangzhou is normally consolidated or under-consolidated,and the soil below the depth of 150 m is generally over-consolidated.The inelastic water release deformation is an important factor affecting the change of land subsidence rate in this area.Using the improved method,the CWL in Cangzhou,Suning and Dongguang is 66.8 m,67.5 m and 67.8 m,respectively.Based on the data of the cumulative land subsidence and groundwater level change in the urban of Cangzhou,we obtain the exponential function relationship between the cumulative land subsidence and groundwater level.The subsidence rate is taken as the index,and the critical groundwater level in the urban of Cangzhou ranges from 65 to 70 m.On the basis of verifying the consistency of the calculation results of the two methods,we determined 65 m as the critical groundwater level for the prevention and control measures of land subsidence in Cangzhou.The results provide a reliable basis for the local government to formulate a reasonable groundwater exploitation plan.

关 键 词：沧州 地面沉降 临界水位 超固结土 形变机理 

分 类 号：P642.26[天文地球—工程地质学]