论文标题:金沙江溪洛渡水电站坝区地应力场及地下洞室群围岩稳定性数值模拟
Numerical Simulation of The Damsite Zone Geostress Field and The Stability of Surrounding Rockmass of The Underground Cavern Group in Xiluodu Hydroelectric Power Station
论文作者 李攀峰
论文导师 陶连金;张倬元,论文学位 硕士,论文专业 岩土工程
论文单位 成都理工学院,点击次数 83,论文页数 118页File Size5968k
2001-05-01论文网 http://www.lw23.com/lunwen_123476372/ 水电站,地下洞室群,岩体结构,地应力场, 数值模拟
hydroelectric power station, underground caverns, rockmass structure, geostress field, numerical simulation
拟建的金沙江溪洛渡水电站是继三峡工程工程之后的又一巨型水利枢纽。该工程布置有大规模的地下厂房洞室群，其规模在国内外已建和拟建工程中是极为罕见的。地下厂房布置于二迭系峨眉山玄武岩（P_2β）岩层中。总体上说，地下厂房区岩体质量较好。但由于多期的构造作用，在厂房区岩层中发育有层间错动带、层内错动带和基体裂隙等不同级别的结构面，局部出现层内错动带的集中分布，使岩体强度降低，质量下降；加之洞室的开挖断面如此之大，造成的围岩应力调整与重新分布必然强烈，洞室周围岩体中的应力重分布可能在洞周围产生强烈的应力集中，从而导致洞周围岩的破坏，尤其是层间错动带的存在，必然加剧围岩的破坏。同时，围岩的稳定性还与岩体所处的初始应力场有关。因此，选取坝区地应力场数值模拟拟合与地下厂房洞室群围岩稳定性分析作为论文的主体。在详细调查厂房区基础地质条件的基础上，系统研究了厂房区的岩体结构特征；在已有研究和测试成果的基础上，以地下厂房区为重点进行了坝区地应力场的三维数值模拟拟合研究；同时，运用有限元法分别对左右岸地下洞室群的三大厂房围岩进行稳定性分析，并对比分析了左右岸厂房稳定性的差异；最后，进行了初步的支护设计。
Abstract: Xiluodu hydroelectric power station of Jinsha kiver is another planned giantproject only second to the Thre Gorges Project in China. The dimension of theundengound chambers located in the mountains in Permian Emei Mountain Basalt strataon the bank of Jinsha kiver is qute large in the world. As a whole, the rockmass qualityis qnde good. Bllt the discolltinuities such as interlayer shearng belts, illtrastfatal-shearing belts and joints randomly distributing in the strata, wosened the strellgth andlowered the quality of the rDCkmass. Additional1y the size of the opening section is so -lnye that the stress redistribution and adjustment around the caverns should be intensive.And the stress redistribution and adjustment may lead to violent stress concelltration," Which, in tal may l7ad to failure of sorounding rockmass. When inierayer shearingbelts exist, the probabilop of surrounding roclanass failure would be inerased badly Thesurroundillg rockmass stability is associated with the fethee of initial geostress field too.So numerical simulation of the initial geostress field and the stabilop analysis ofundWund caverns is selected as the topic of this paPer Based oll careful fieldgeological investigaton of the basic geological conditions, the surrounding roCkmassstubo of undengound chambers is studied systematically in this paPer Then thegeostress field at the damsite zone is simulatCd and analyzed according to the dataobtained. At the same time, the stability of three main chambers among the undergroundcaverns on both banks is analyzed with 3D- o software and the differences b0tween themain chambers on both banks are discussed. At last, initial suPpOrt measure design forthe caverns is suggested.
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