北京市平原区典型地裂缝发育特征及成因机制研究

发布时间：2018-03-30 07:52

本文选题：北京地裂缝　切入点：分布发育　出处：《中国地质大学(北京)》2017年硕士论文

【摘要】：地表土层会在构造活动、自然应力和人类活动的作用下产生开裂,当其具有一定长度和宽度且致灾时,则称其为地裂缝,属地表变形破坏的一种。地裂缝会破坏土层的连续性,对建筑物及农田水利等造成严重破坏。我国华北地区是地裂缝的高发地区,给城市发展建设和人们的生产生活带来了严重的影响。北京作为我国首都,改革开放后的近30年来,人口不断涌入致使北京市快速扩张,水资源使用量极大,在原有水资源供给不足的情况下,地下水资源的抽取量逐年加大,地面沉降加剧,形成沉降中心,致使地裂缝活动异常,成为制约北京市发展规划的重要地质问题。地裂缝的形成和扩展不仅会改造地表,引发地面沉降等次生地质灾害,也会对道路、桥梁、管道、建筑等基础设施带来破坏,因此对地裂缝成因机制的研究具有十分重要的工程和实际意义。本文以北京市平原区地裂缝分布及发育特征为基础进行区划,研究了北京市各地裂缝种类及典型地裂缝黄庄-高丽营地裂缝的具体分布及成因机制。论文主要研究内容及成果如下:(1)通过收集资料和阅读文献,获得北京市的自然条件、地形地貌、地层岩性、地质构造、水文地质条件和常见地质灾害的资料,在此基础上研究北京市平原区地裂缝的整体分布及发育概况。综合分析可得出北京平原区地裂缝优势方向为NE向,活动性较强的地裂缝均与断裂带相伴相生;北京市平原区地裂缝分布具有明显的地域性特征,据此划分为6大地裂缝带分布区域。北京市活动性最强的地裂缝带为黄庄-高丽营断裂诱发的黄庄-高丽营地裂缝带,其次是顺义区内由顺义-良乡断裂主导的北小营镇地裂缝及顺义城区地裂缝。黄庄-高丽营地裂缝带与顺义城区及北小营地裂缝带属于依附于活断层由过度抽水引发开裂的抽水地裂缝。基于此,在《工程地质学报》发表文章《北京市地裂缝分布与发育规律》一篇。(2)对典型地裂缝黄庄-高丽营地裂缝进行深入研究,分析其致灾及发育特征,同时在黄庄-高丽营地裂缝破裂带取土样进行室内密度、含水率、颗分及抗剪强度试验,得到数值模拟的参数。黄庄-高丽营地裂缝沿黄庄-高丽营断裂发育,通过黄庄-高丽营地裂缝周边取土进行室内试验可得,黄庄-高丽营地裂缝破坏区的土为明确的粘砂互层结构。在这种互层结构中砂土的固结系数较大,比粘性土的固结较快,因此在抽水过程中,砂土和黏土的固结速度不同,上下盘容易产生差异沉降。(3)利用有限差分软件Flac~(3D)进行断层面和断层体贯穿模型试验,并作为辅助资料对黄庄-高丽营断裂带隐伏时期的基岩运动进行贯穿模拟,分析构造运动与水的渗流在地裂缝产生过程中的作用。通过试验数值模拟可以得出,隐伏断裂由于基岩运动在隐伏断裂两侧逐渐产生裂缝向上传播,至地表后,由于水的渗流作用向两侧附近扩展。同时,水的渗流对扩大地表破裂有很大的作用,通过对隐伏断裂时期的数值模拟可以看出,先存断裂对地裂缝的产生有不可忽视的作用。
[Abstract]:The surface soil in the tectonic activities, natural cracking force and human activity, when it has a certain length and width and the disaster, called the cracks, is a kind of surface destruction. Continuous cracks will destroy the soil, causing serious damage to buildings and farmland water conservancy. North China is to crack prone areas, has brought serious influence to the development of city construction and people's production and life. Beijing as the capital of China, after the reform and opening up in the past 30 years, resulting in the rapid expansion of population influx into the city of Beijing, a great quantity of water resources use, in the original water supply under the condition of extraction of groundwater resources increased year by year, land subsidence intensified, the formation of settlement center, resulting in abnormal ground fissures, become the important geological problems of development planning of Beijing city. The crack formation and expansion not only Will the transformation of surface, the ground subsidence and other secondary geological disasters, but also on roads, bridges, pipelines, buildings and other infrastructure facilities bring destruction, so the research on crack formation mechanism has very important practical significance. Based on the engineering and Beijing plain ground crack distribution and development characteristics as the basis for the Division, research Beijing city around the crack type and typical crack distribution and formation mechanism of concrete Huangzhuang Korea camp cracks. The main research contents and results are as follows: (1) through the data collection and reading literature, Beijing natural conditions, topography, lithology, geological structure, hydrogeological conditions and frequent geological disasters the overall data, distribution and development of cracks in the plain areas of Beijing on the basis of comprehensive analysis. The plain area of Beijing ground fissure advantage in NE direction, strong activity The ground fissure and fracture zone concomitant; distribution in the plain areas of Beijing ground fissures have obvious regional characteristics, it is divided into 6 regions. The strongest earth fissure zone distribution Beijing city the activity of ground fissures in Korea Huangzhuang Huangzhuang fault induced Camp Camp Korea fracture zone, followed by Shunyi District in Shunyi Liangxiang fault leading Beixiaoying town to crack and ground fissures in Shunyi city. Korea Huangzhuang camp and fracture zone of Shunyi city and Beixiaoying ground fissure belt belongs to depend on active faults by excessive pumping pumping caused cracks. Based on this, the "Beijing City crack distribution and development rule > Article published in < >. Journal of Engineering Geology (2) to conduct in-depth research on the typical crack Huangzhuang Korea camp crack, the hazard analysis and development characteristics, and rupture zone of soil sample for indoor density in Korea Huangzhuang camp containing cracks. The rate of water, and a shear strength test, numerical simulation parameters are obtained. The Korea Huangzhuang Huangzhuang Korea camp along the crack development camp fracture, laboratory tests were made available through the camp Korea Huangzhuang Huangzhuang Korea surrounding soil cracks, crack damage zone camp soil as clear sand interbedded sand in the structure. The structure of the consolidation coefficient is bigger, faster than the consolidation, therefore in the pumping process, consolidation velocity of sand and clay in different footwall prone to differential settlement. (3) by using the finite difference software Flac~ (3D) of fault plane and fault body through model test, and as supplementary information the Korea Huangzhuang fault zone during the period of camp buried bedrock motion throughout the simulation, seepage analysis of tectonic movement and water production function in the process of crack. Through the test of numerical simulation can be drawn, because the movement of bedrock buried fault Gradually cracks propagating upward in buried fault on both sides, to the surface, due to the seepage of water is extended to near both sides. At the same time, the water seepage on the expansion of surface rupture has great effect. Based on the numerical simulation of the buried fault period can be seen, first deposit has a role can not be ignored fault on ground fissures.

【学位授予单位】：中国地质大学(北京)
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：P642.2

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