【作者】 王朋朋；

【导师】 李新生；

【作者基本信息】 长安大学 ， 地质工程， 2009， 硕士

【摘要】 地裂缝是西安地区典型的地质灾害,对各类工程建筑、交通设施、城市生命线工程及土地资源造成破坏,过去已给古城西安的城市建设带来了巨大的经济损失。目前,西安地铁正处建设中,地铁线路穿越了多条地裂缝,解决地裂缝带的结构和防水措施成为西安地铁设计和施工的关键问题之一。西安地铁二号线北大街段在施工过程中出现涌沙和降水困难等问题,严重影响了地铁规划和施工。因此研究地裂缝带土体的渗透性质,掌握地裂缝带地下水的运移特征,有助于对地铁施工基坑降水进行合理设计,也有助于地裂缝带的工程结构和防水措施的优化设计。本文结合作者参与的地铁一号线劳动路小学跨地裂缝带水文地质试验的成果及以往的资料,首先对试验场地的地形地貌、地层结构、地质构造和水文地质条件进行了介绍,然后对试验方案进行了设计,包括抽水井和观测孔的布置、结构及施工工艺,试坑渗水试验方案、钻孔降水头注水试验方案和抽水试验方案。其次,本文分别对试坑渗水试验、钻孔降水头注水试验和抽水试验过程进行了详细描述。同时利用多种方式对试验资料进行整理和分析。通过抽水试验得出地裂缝带的渗透系数最大,下盘次之,上盘最小,地裂缝上下两盘水力联系较弱,两盘地下水补给来源可能不同,抽水试验造成的地面沉降集中在地裂缝带上。最后,本文通过多个方面对水文地质试验的结果进行分析。通过对地裂缝带土体物理力学性质研究发现,场地上下盘土体性质差异不大,含水层的错断导致了上下两盘水力联系较弱,通过有限元软件对地裂缝上盘的建筑物对场地土体施加的影响进行分析,结果表明:地裂缝上盘的建筑物对土体施加的荷载造成了土体性质的改变,影响了试验结果,导致上盘水源补给较为困难,渗透系数偏小。更多还原

【Abstract】 Ground fracture is a typical regional geo-hazard, which bring damage to various types of buildings, transportation facilities, city lifeline projects and the land resources.The hazard has brought enormous economic loss to the construction of Xi’an in last several years. Now, Xi’an Subway is under construction. About 15 ground fractures are crossed by the subway, which will bring adverse effect to the subway construction and operation. Therefore, it is a great question of xi’an subway design and construction to solve the structure and Water-proof measure of ground fractures.Based on the fracture hydrogeology test results and previous data of xi’an subway Line 1, which carried on laodonglu school,the geological structure, landscape features, formation lithology and hydrological of the test site are introduced firstly. Then the test plan is designed,which include the layout, structure and the construction technology of the pumping wells and observation hole, the plan of the field seepage test, plan of the precipitation in the first test drilling water and the plan of the pumping test.Secondly,the process of the field seepage test, recipitation in the first test drilling water and the Pumping test are detailed description in this paper. A variety of ways are used to arrange and analyse the test dataThrough the pumping test,the permeability coefficient of the fracture zone is the largest,the under plate of the fracyure is the second,the upper plate of the fracture is the leastThe water contact of the both sides of the fracture is weak.the water Supply source of the both sides may be different.Finally, analysis are carried on the results of the hydrogeological test through several ways.Through the research on the physical and mechanical properties of rock and soil of the fracture,we can found that the difference of the physical and mechanical properties of rock and soil between the two sides is small,the break of the Aquifer cause the weak of the water contact between two sides of the fracture,The infiuence of the building imposed on the upper side of the fracture is simulated by using 2-D finite element software in this paper, and the results show that the load caused change of the Soil properties,which is imposed on the upper side of the fracture by the building, influence the test results,cause the water supply become difficult and the permeability coefficient is smaller.更多还原