云桂铁路珠琳段岩溶发育特征及其对工程影响研究

发布时间：2018-11-02 07:20

【摘要】：我国碳酸盐岩分布广泛,尤其在西南的滇、黔、桂等地区,岩溶发育非常强烈,对铁路公路等线状工程的建设和运行带来了很大的危害。能够针对岩溶路基提出行之有效的工程治理措施意义重大。新建云桂铁路在云南境内约434km,沿线碳酸盐岩分布广泛。在珠琳段各种岩溶形态都相对发育,地表岩溶及地下岩溶对铁路建设的不良影响显著。因此本论文选取新建云桂铁路珠琳段作为研究对象,在现场调查的基础上对其岩溶发育特征及其对工程的影响进行研究。本论文所做的研究目的如下：通过现场调查、现场试验及其钻孔资料查明试验段岩溶发育特征,进而提出针对性整治措施,并对现场注浆整治前后的地下水消散过程及形式进行数值模拟,以此对整治措施的可行性进行表征,并对现场整治进一步优化。本论文的主要研究内容和成果如下：(1)对研究区以及试验段地质情况的深刻认识,云桂铁路珠琳段位于滇东南高原地貌区,此处基岩几乎为碳酸盐岩,可溶蚀性强,构造相对发育。(2)在对试验段的现场钻孔资料统计和现场试验完成后,分别对四个小段的基岩面起伏情况、表层溶蚀破碎带起伏情况,地下溶洞的发育情况,覆盖层厚度变化情况,地下水位的变化情况进行了分析总结,得到试验段岩溶发育规律。(3)新建云桂铁路全线43.7%为岩溶线路段,对试验段沿线可溶岩的分布特征、组合形式,岩溶发育程度进行总结,发现洼地是分布最为广泛、产生危害最高的岩溶发育形态。其中峰丛洼地和溶丘洼地作为最常见的溶蚀地貌,分别占岩溶线路段的44%、26%。因此将峰丛洼地和溶丘洼地的发育作为研究重点。(4)珠琳试验段主要分布于旧莫河和南丘河中部的分水岭地区。其中洼地的演化具有双向性,既受区域河流溯源侵蚀波及的影响,还继承古溶原面上自身演化的特征。具有较为典型的补给型洼地特点：以浅碟形为主；地下岩溶空间不大但相对均匀；土层厚度大,结构多元；地下水位埋藏较浅,动态变化不大。(5)论文采用数值模拟的方法得到,覆盖层微小变形洼地对岩溶路基来说威胁较小；中心塌陷洼地继续产生塌陷的可能性极大；竖井连通洼地只要避让竖井中心,基本不会产生病害。(6)论文最后根据珠琳试验段现场条件,对四个小段提出了针对性很强的整治措施,并对注浆效果进行了评价。
[Abstract]:Carbonate rocks are widely distributed in China, especially in Yunnan, Guizhou, Guangxi and other areas in the southwest, karst development is very strong, which has brought great harm to the construction and operation of railway and highway projects. It is of great significance to put forward effective engineering treatment measures for karst subgrade. The newly-built Yunnan-Gui Railway is located in Yunnan Province with a wide distribution of carbonate rocks. All kinds of karst forms are relatively developed in Zhulin section, and the surface karst and underground karst have a significant negative effect on railway construction. Therefore, this paper selects Zhulin section of the newly built Yun-Gui Railway as the research object, and studies its karst development characteristics and its influence on the project on the basis of field investigation. The purpose of this paper is as follows: through field investigation, field test and borehole data to find out the characteristics of karst development in the test section, and then put forward targeted remediation measures. The process and form of groundwater dissipation before and after grouting treatment were numerically simulated to characterize the feasibility of remediation measures and to further optimize the field remediation. The main contents and achievements of this paper are as follows: (1) from the deep understanding of the geological conditions in the study area and the experimental section, the Zhulin section of Yun-Gui Railway is located in the geomorphological area of the southeastern Yunnan Plateau, where the bedrock is almost carbonate rock, which has strong solubility and erodibility. The structure is relatively developed. (2) after the statistics of field borehole data and field test are completed, four small sections of bedrock surface fluctuation, surface dissolution and fracture zone fluctuation, underground karst cave development are respectively studied. The variation of overburden thickness and groundwater level are analyzed and summarized, and the karst development law of the test section is obtained. (3) 43.7% of the whole railway line of Yunnan-Gui railway is the karst section, and the distribution characteristics of the soluble rock along the test section are discussed. Combining form and karst development degree, it is found that the depressions are the most widely distributed and the most harmful karst development forms. Among them, the peak cluster depression and the dissolved hill depression are the most common karst landforms, accounting for 44% and 26% of the karst section, respectively. Therefore, the development of peak cluster depression and dissolving hill depression is regarded as the focus of the study. (4) the Zhulin experimental section is mainly distributed in the watershed area of the middle part of the Old Mo River and the South Qiu River. The evolution of the depressions is bidirectional, which is affected not only by the traceability of the regional rivers, but also by the evolution of the paleolysin surface. It has the characteristics of typical recharge type depressions: shallow saucer shape, small but relatively uniform underground karst space, large thickness of soil layer and multiple structures; The underground water level is shallow and the dynamic change is not so great. (5) the paper uses numerical simulation method to get the conclusion that the small deformation depressions of overburden are less threatening to the karst subgrade, and the possibility of the center collapsing depressions continues to be great. In the end, according to the field conditions of Zhulin test section, four segments are put forward, and the grouting effect is evaluated.
【学位授予单位】：西南交通大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U212.22;P642.25

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