【作者】 谭红艳；

【导师】 蒋小珍；

【作者基本信息】 中国地质科学院 ， 地质工程， 2009， 硕士

【摘要】 白云区位于广州市北部,区内存在大量未处理的采空区,且有大面积的覆盖型岩溶区,随着白云区内城市建设项目,尤其是地下建设工程的不断增多,严重扰动了原来相对稳定的地质环境,地面塌陷也逐渐成为该地区的主要地质灾害之一。因此,对白云区进行地面塌陷危险性预测评价有着及其重要的意义。本文主要从岩溶塌陷和采空塌陷两方面进行研究:一、采空塌陷的预测评价调查发现,白云区主要分布有嘉禾煤矿和大朗煤矿,煤矿采空后,留下采空区、小煤窑未经处理,且巷道大部分采用全面冒落法管理,因此,在自重的作用下,其顶板很容易发生弯曲、张裂、冒落,从而在地表形成塌陷坑。本文主要从洞室稳定性角度,通过力学分析,分别选用了洞顶坍塌堵塞法、普氏平衡拱法对采空区、巷道、小煤窑的稳定性进行了评价。结果表明,矿区整体稳定性较好,顶板埋藏越深,稳定性越好;位于-150m至地表间的则明显不稳定,易于出现地面塌陷,这与实际野外调查结果比较符合。此外,矿坑涌水也是地下工程建设施工中常遇到的一类重大地质灾害,本文根据矿坑和小煤窑的涌水量、地势、蓄水条件、断层裂隙分布等信息,借助ArcGIS软件的空间分析功能,对其涌水危险性进行了分析,并得出了涌水危险性较大的区域分布。二、岩溶塌陷的预测评价白云区内分布的石炭系、二叠系均有可溶性碳酸盐岩,其中以壶天群岩溶最为发育。随着人类活动的加剧,地下水位大幅下降,从而导致岩溶塌陷的发生。通过对影响岩溶塌陷的各因子进行分析研究,选用了层次分析法对多因子赋权值,建立岩溶塌陷地质模式,借助GIS软件的空间分析功能对白云区岩溶塌陷危险性进行了预测评价。结果显示,夏茅村存在塌陷地可能性较大,这与实际情况比较符合,说明评价结果具有一定的参考价值。最后,对评价结果进行综合,得到白云区地面塌陷危险性高的区域面积为6.8km~2,约占整个评估区的13.7%,中等危险区占43.5%。其中市医药公司、大冈村、夏茅村、潭村、同德围、南约、夏茅煤矿、市矿务局第一煤矿、第二煤矿地面塌陷发生危险性较高;下村、北约、体育中心发生地面塌陷危险性相对较低;棠下村、萧岗村、南航新村、石岗新村、鹤边、尹边、罗岗相对稳定。建议在工程设计时,尽可能绕避最危险的地方;对不能绕避的采空区、塌陷区可以根据实际情况采取灌浆等工程措施;对已塌陷地区进行填堵、夯实,或者直接跨越;对于工程的设计应加强对建筑物的整体性及缩短变形缝等措施的处理。更多还原

【Abstract】 Baiyun District, Guangzhou, exists a large number of abandoned coal districts and covered karst areas. With the rapid development of urban construction, especially the underground construction, the original geological environment was seriously disturbed, and the surface collapse has become one major geological hazard, so it’s important to evaluate and predict the risk of collapse .The author has researched from two parts in the dissertation:1. The prediction and evaluation about the Mining collapseThere are two coal districts including four coal mines, Jiahe no2, no3, no4 Mine and Dalang Mine. All of the abandoned mines had been closed before 1997, and suffered the mining collapse hazard.The paper has analyzed the cavern stability by the collapse balance method and the M.M. Promojiyfakonkv arch Theory. The result showed the abandoned coal districts were only instability above -150m.Besides, the mine discharge was another disaster in the mine-out area. The paper zoned the risk by analysis the discharge environment elements.2. The prediction and evaluation about the karst collapseBaiyun district distributed of Carboniferous and Permian carbonate, and the human activity is another main element of karst collapse. By learning from the main elements of the karst collapse, it’s evaluated by Analytic Hierarchy Process.In summary, the high risk area are 6.8 km~2, accounting for about 13.7percent, for example, Dagang, Xiaomao and so on; the medium risk area are 43.5 percent. It’s should be avoided the high risk area as far as possible or taken some engineering measures, such as grouting. For projects designed should enhance the integrity of buildings and shorten the processing slot.更多还原