【作者】 韩蒙；

【导师】 巫锡勇；

【作者基本信息】 西南交通大学 ， 地质工程， 2012， 硕士

【摘要】 路基是车辆安全平稳运行的保障,公路、铁路的路基必须具有较高的强度、耐久性和较好的稳定性,并能抵抗各种因素影响下的沉降变形。岩溶塌陷引起的地表失稳主要表现为普遍性、复杂性以及它的难以预测性。作为地质灾害,给社会带来了巨大的损失。受岩溶发育的不均匀性影响,岩溶塌陷的发育在空间上具有隐蔽性、发育过程具有累进性、塌陷的发生又具有突发性特点,是覆盖型岩溶区交通工程建设面临而且有难以解决的主要岩溶病害问题,严重影响交通建设和安全运营。西部作为我国岩溶分布的主要地区,在实施西部大开发的背景下,对岩溶地质灾害的研究更体现出其重要性。因此有必要对岩溶路基的塌陷危险性进行评价。本文首先在针对云桂铁路岩溶塌陷实际工程问题的调查基础上,对试验段岩溶地质条件进行分析。试验段地层较为平缓,没有大型沟谷切割,地表出露地层有限。地质构造相对简单,发育两条较具规模的断层,即绕马路断层和沙子塘断层,地表特征不甚明显。试验段地处缓坡较强径流带,地下水位的变化受大气降雨的影响较大。本次研究根据现有的试验勘探,以钻孔勘探资料为主,结合地表调查和区域地质资料,对地下水动力条件、覆盖土层物质组成及结构特征、地下岩溶发育程度等各项影响岩溶塌陷的因素进行评价分析。根据各个单项指标的基本特征,定性划分三个等级：易于、较易于和不易于导致塌陷,并将试验段沿线进行单项指标特征分区,形成较差、中等和较好区。然后结合各段主要塌陷机理,耦合各单项指标进行综合分析评价。最后根据以上方法对各试验区段进行具体分析,并结合各区段实际自然地质条件和人类活动影响特征,对试验段岩溶塌陷机制及其危险性进行综合评价与预测。从而给出各段岩溶路基整治措施的建议。更多还原

【Abstract】 The subgrade would guarantee the train being drived safely and smoothly. The railway and highway subgrade has to be with the high strength and the strong durability and the better stability. The surface instability which is karst collapse leaded to are mainly universal, complex and unpredictable. As a kind of geological disasters, it brought great losses to the community. By the nonuniformity of karst development, the karst collapse in space is concealed, its developmental process is progressive, and its occurrence is sporadic. In covered karst area, karst collapse is the main karst disease problem difficult to solve in the building of traffic engineering, and it seriously affect transport construction and safe operation. Western of China is the main areas of karst. In the context of the western development, the study of karst hazards reflects its importance. Therefore it is necessary to evaluate the risk of karst collapse of roadbed.Firstly, on the basis of the investigation of practical problems for Yun-Gui railway, this article analysis the karst geological conditions of test section Strata of the test section is relatively flat. There is no large gully cutting, and the outcrop of the strata is few. The geological structure is relatively simple. There are two little larger faults, Raomalu fault and Shazitang fault, which surface features are not so obvious. The test section is located in the gentle slope and strong runoff zone, and the groundwater level is influenced by rainfall.This study based on existing test exploration, in order to drill exploration data, combined with surface surveys and regional geological data, analyzed and evaluated the factors affecting, for instance the dynamic conditions of groundwater, the material composition and structural characteristics of the overlying soil, the underground karstification level etc.According to the basic characteristics of each individual indicators, it is qualitatively divided into three levels: easy, easier, and not easily leading to collapse. Based on division of each individual indicators, test section is divided into poor area, and middle area and better area. Then the individual indicators were coupled and analyzed, combined with the main collapse mechanism of each section.Finally, based on the method, combined with the natural geological conditions of each section and the characteristics of human activities, the mechanism and risk of karst collapse were evaluated and predicted comprehensively. Thus the suggestions of regulation measures of karst roadbed were given.更多还原