【作者】 许延春；

【导师】 张玉卓； 刘天泉； 耿德庸；

【作者基本信息】 煤炭科学研究总院 ， 采矿工程， 2002， 博士

【摘要】 本文作者基于现场实测、试验室专门试验、专用软件的数值分析，较深入研究了黄淮地区深厚含水松散层的工程性质、变形及其在井筒破坏治理工程中的应用，其主要工作有。 1) 根据多个矿区土工试验结果，对深厚粘土物理陛质的变化规律进行了分析，提出黄淮地区大于70m的松散层为深厚松散层；提出深部粘土可固结厚度的概念。研究了深厚粘土强度随埋深和湿度变化的规律，提出深部粘土存在强度弱面和深部粘土“上、下限强度”的概念和选取方法。 2) 通过2项专门的试验，即，深部粘土高压入渗和密实砂土的“双控”三轴压缩试验。证明深部粘土与承压含水层接触面附近可形成强度弱面；含水层水压越高则可压缩范围就越大；证明下限强度可按有效应力相等，物性类似的浅部粘土强度值选取；深部砂土用有效应力原理进行的试验与按模拟自重状态的试验相比，当埋深一定，含水层孔隙水压力较大时，结果存在一定的差异。表明有必要进一步试验研究深部砂土的特性。 3) 分析了黄淮地层深厚含水松散层的结构特征以及矿井疏水对松散含水层水位的影响。提出了松散层结构区域上的类似性和局部上的多变性；研究了矿井水动态类型以及采矿对松散层水体的影响，为分析井筒破坏机理和深厚松散层性质、变形特征打下了基础。 4) 根据观测结果，研究了松散层竖向压缩变形特征，建立了计算模型；观测认识到深厚松散层存在集中水平移动现象，研究表明集中水平移动发生在深部厚层粘土与砂土的交界面处。上述研究成果对实施合理的井壁破坏防治工程有重要指导价值。 5) 通过分析井筒卸压槽应力、变形观测结果与松散层变形的关系，对采用卸压槽治理井筒破坏有指导价值；根据建筑物已有裂缝调查和不扩展观测结果，提出大范围的地表沉降对工业场地内的建筑物一般在短期内不会造成损坏影响的认识。 6) 开发了专用的有限元软件，从而建立了井壁——土层——疏水固结的统一模型，对地层压缩导致井壁附加应力的产生、卸压槽防治井筒破坏的原理和特点、地层注浆防治井壁破坏的机理进行了较合理的计算分析，得出地层注浆措施的优选方案，对工业场地内松散层的集中水平移动机理进行了研究，认为地层弯曲变形是产生集中水平移动的重要原因之一。以上认识对实际治理工程有重要的指导价值。 7) 本项目的观测和研究结果，在制定兴隆庄矿西风井二次破坏治理工程方案中已经获得应用，包括，分析井筒二次破坏原因、预计地层压缩量、卸压槽设计及选位，确定地层注浆优化参数，提出了破壁深孔注浆措施等更长效、经济的治理工程方案。更多还原

【Abstract】 Based on numerical analysis with special FEM(Finite Element Method) software , the observation in-situ and the special tests in lab, the author has studied the engineering and mechanical properties, characteristic of deformation of the deep and thick water bearing unconsolidated layers in Huanghuai area, the author has also studied its application in preventing the shaft wall from failure. The work involved:1) According to the test result of the soil in several coal mines, physical properties and its variation of deep and thick clay were researched The layer of deeper than 70m is named as the Deep and Thick Layer according to clay properties. And the idea of potential consolidation thickness of deep clay was proposed. Characteristic of the strength of the deep clay was also studied varying with the depth and the water content. In addition, the author proposed the concept of weak face, upper and lower strength limit of deep clay, together with the method to determine them.2) Two special tests were made. One is the high pressure seeping test of deep clay, another is triaxical compressing test with controlling two factors of tight sand. The first test testified the existence of weak face at the interface between the deep clay and the artesian aquifer. Compression area will be larger if the pore water pressure being higher in the water bearing layer. Lower strength limit of the deep and thick clay can be determined according to the strength of the shallow clay with equal effective stress and similar physical properties. Discrepancy was found between some test results with equal pressure and higher pore water pressure based on Principle of Effective Stress and that by simulation of gravity of the tight sand. These will be useful for further research on deep sand.3)Based on analysis of the structure of the deep and thick water bearing unconsolidated layers in Huanghuai area and the study of the influence of mine withdrawing water on water bearing layer, the author presented the similarity of the structure of the layers in mining field and its variability in local area The author also analyzed the relationship between mine withdrawing water and the water level of the aquifers, which is helpful for the study on the mechanism of shaft wall failure and the study on the characteristic of properties and deformation pattern of deep and thick water bearing unconsolidated layers.4)Referring to the observations in coal mine, the author analyzed the characteristic of consolidation and compression in the layers, and constitute the model to calculate the compressing on the basis of the water level, compressing time and the compressing ratio of the layers. The author also studied characteristic and mechanism of the concentrated horizontal movement first observed in China in the deep layers, together with its influence on the shaft walls. These will be useful in studying the prevention of the shaft wall from failure.5)The observation results of the stress and deformation of stress releasing notch in shaft walls were studied, which is useful for preventing shaft walls from failure by stress releasing notch. According to the surveying of cracks in buildings, the author pointed out that settlement in large scale generally does no harm to the building in mining industrial area.6)Numerical analysis with special FEM software was made to constitute the uniform model on shaft wall-soil layer-consolidation. Additional stress induced by deep unconsolidated layer’s compression, mechanism and characteristic of stress releasing notch’s effect on the prevention of shaft wall from failure, the optimum plan and the effect of grouting and the mechanism of the concentrated horizontal movement of the deep unconsolidated layers were also analyzed. In addition it was testified that the deflection deformation of the deep layers was one of the main factors of the concentrated horizontal movement of soil layer in mining area was made, which is important for treatment engineering in practice.7)The study presented in the paper has been us更多还原