西藏怒江松塔水电站坝区岩饼及片帮形成机制研究

发布时间：2018-06-01 16:22

本文选题：松塔水电站 + 高地应力　；参考：《成都理工大学》2014年硕士论文

【摘要】：我国西部水资源丰富，水电项目是西部大开发任务的重中之重。许多水电项目都涉及到坝区的高地应力问题。对高地应力问题的研究除了用各种试验方法测得直观的数据，还可以通过对高地应力现象如岩饼、片帮的研究来判断该区域的地应力状况。本文以西藏怒江松塔水电站坝区岩饼以及片帮为研究对象，在了解了国内外研究现状的基础上，在野外调查中做了大量的钻孔岩饼和平硐片帮编录工作，结合现场平面水压致裂法和空间应力解除法试验数据，分析研究了坝区河床钻孔岩饼的发育特征、平硐片帮的发育特征，总结了坝区的地应力分布特征。同时采用数值方法，对岩饼以及片帮的形成过程进行了模拟，分析了形成过程中的应力重分布状况，最后得出松塔坝区岩饼及片帮的形成机制。具体研究内容成果如下：（1）对平面水压致裂法和空间应力解除法地应力实测结果进行统计分析，，得出了松塔坝区水电站左右岸以及河床的最大主应力、最小主应力、中间主应力的大小。分析得出最大水平主应力的优势方向。（2）对岩芯编录资料进行整理，分析了坝区岩饼的空间分布特征以及岩饼的几何形态特征，总结了岩饼发育的影响因素。据经验公式估算出了坝区岩饼形成的临界应力。用FLAC3D数值计算方法模拟岩饼的形成过程总结出了岩饼形成的三种类型，结合松塔坝区实际情况，判断该坝区岩饼的形成机制。（3）对片帮编录资料进行整理，分析了坝区的平硐片帮空间分布特征、片帮破裂面的特征、片帮发育影响因素。对片帮发育程度进行了分级。对片帮样品做了微观测试研究，通过电镜扫描得到的图像来判断片帮的形成类型和初始地应力的方向。同时，作者用FLAC3D数值计算方法模拟片帮的形成过程，研究了片帮发育部位以及发育程度与初始地应力场的最大主应力之间的关系，结合工程实际情况，判断该坝区片帮的形成机制。
[Abstract]:Water resources are rich in Western China. Hydropower projects are the most important task of western development. Many hydropower projects are involved in the high stress problem in the dam area. The condition of ground stress.
In this paper, taking the rock cake and the slice of the dam area of the Nu River of Nu River in the dam area as the research object, on the basis of understanding the present situation at home and abroad, a large number of drilling rock cake and cavern help cataloging work have been done in the field investigation, and the river bed drilling in the dam area is analyzed and studied in combination with the field plane water pressure cracking method and the test data of the spatial stress relief method. The characteristics of the development of the rock cake and the development characteristics of the cavern slice help have summarized the distribution characteristics of the geostress in the dam area. At the same time, the numerical method is used to simulate the formation process of the rock cake and the slice help, and the stress redistribution in the formation process is analyzed. Finally, the formation mechanism of the rock cake and the slice gang in the pine tower dam area is obtained. The concrete research content results are as follows. Below:
(1) according to the statistical analysis of the in-situ stress measured results of the plane hydraulic fracturing and the spatial stress relief method, the maximum principal stress, the minimum principal stress and the middle principal stress of the river bed in the hydropower station of the pine tower dam area are obtained, and the dominant direction of the maximum horizontal principal stress is analyzed.
(2) to sort out the rock core cataloguing data, analyze the spatial distribution characteristics of the rock cake in the dam area and the geometric shape characteristics of the rock cake, and summarize the influence factors of the development of the rock cake. According to the empirical formula, the critical stress of the formation of the rock cake in the dam area is estimated. Three kinds of the formation of the rock cake are summed up by the FLAC3D numerical calculation method. Based on the actual situation of the dam, the formation mechanism of rock cake is determined.
(3) to sort out the data of the sheet Gang cataloguing, the characteristics of the space distribution of the cavern section, the characteristics of the fracture surface and the influence factors of the development of the slice help were analyzed. The development degree of the slice help was classified. The microcosmic test of the slice help samples was done. The formation type and initial crustal stress were judged by the image image obtained by the scanning electron microscope. At the same time, the author uses the FLAC3D numerical method to simulate the forming process of the flakes, and studies the relationship between the development position of the flakes and the maximum principal stress of the initial geostress field. The formation mechanism of the section of the dam is judged by the actual situation of the project.
【学位授予单位】：成都理工大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TV221.2

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