本文選題：右壩肩邊坡 + 緩傾結(jié)構(gòu)面��； 參考：《成都理工大學》2014年碩士論文

【摘要】：擬建牙根二級水電站是雅礱江中游規(guī)劃的第三個梯級電站，設計重力壩最大壩高153m，右壩肩邊坡開挖高度近210m，最大開挖深度近100m。邊坡斷裂、裂隙發(fā)育，地質(zhì)條件復雜，尤其是受一組順坡緩傾小斷層及裂隙密集帶的控制，邊坡變形強烈，淺表巖體松弛拉裂，穩(wěn)定性較差，工程開挖邊坡存在極大的安全隱患。因此，研究右壩肩邊坡穩(wěn)定性，進而提出相應的支護措施建議，對確保工程施工安全具有重要的實際意義。 本文在查明邊坡賦存的地質(zhì)環(huán)境條件、巖體結(jié)構(gòu)及變形破裂特征基礎上，建立邊坡變形破壞機制的概念模型，采用地質(zhì)分析、剛體極限平衡法及數(shù)值計算方法綜合分析邊坡穩(wěn)定性，進而提出工程邊坡初步支護設計方案。取得了以下主要成果。 （1）邊坡巖性為燕山早期黑云二長花崗巖，以發(fā)育NW向順坡緩傾角結(jié)構(gòu)面為特征，邊坡內(nèi)部發(fā)育的fh01、fh02、fh03、fh04、fh05、fh06長大緩傾角斷層對邊坡的穩(wěn)定性起控制性作用。此外發(fā)育NE向陡傾及NWW-EW向陡傾兩組陡傾角結(jié)構(gòu)面。受巖體結(jié)構(gòu)控制，邊坡巖體普遍沿緩傾角斷層發(fā)生蠕滑拉裂變形，最大滑移變形量可達5m以上（PD53平硐f5303）。巖體風化卸荷強烈，強卸荷水平深度可達108m，，弱卸荷最大水平深度可達153m。 （2）工程邊坡受NW向緩傾角結(jié)構(gòu)面控制，其變形破壞模式為滑移-拉裂型。fh01、fh02、fh03、fh04、fh05、fh06等一系列順坡緩傾斷層作為底滑面，以NNE或NWW向陡傾斷層作為后緣拉裂面，橫河向陡傾長大斷層則構(gòu)成側(cè)向割裂面。 （3）穩(wěn)定性評價結(jié)果表明，右壩肩邊坡整體穩(wěn)定性受控于fh06+f53組合塊體，fh01+f53、fh02+f53、fh03+f53、fh04+f53、fh05+f53大型組合塊體對邊坡的總體穩(wěn)定性亦存在重大影響。天然工況下fh03+f53、fh04+f53、fh04+f555穩(wěn)定性系數(shù)介于0.865-0.901之間，邊坡整體處于不穩(wěn)定狀態(tài)。局部以fh03+f53、fh04+f53組合塊體穩(wěn)定性系數(shù)最低，介于0.865～0.889之間。fh01+f53、fh02+f53、fh05+f53塊體組合穩(wěn)定性系數(shù)介于0.954-1.033之間，邊坡整體處于極限平衡狀態(tài)。暴雨工及地震工況況下，fh01+f53、fh02+f53、fh03+f53、fh04+f53、fh05+f53、fh06+f53組合塊體穩(wěn)定性系數(shù)均小于0.95，邊坡整體處于不穩(wěn)定狀態(tài)。 （4）根據(jù)穩(wěn)定性評價結(jié)果，對右壩肩邊坡不同部位提出了相應的支護措施。邊坡加固設計應按照謹慎開挖、減少爆破、分區(qū)域分層次支護的原則進行，將工程邊坡的整體穩(wěn)定性控制作為邊坡支護措施設計的首要問題，穩(wěn)定性的控制秉從先整體后局部順序進行。右壩肩邊坡穩(wěn)定性受典型的控制性緩傾角斷層坡體結(jié)構(gòu)控制，工程邊坡開挖后，緩傾角斷層切出地表，嚴重影響工程安全性；經(jīng)邊坡下滑力計算結(jié)果可知，以緩傾角結(jié)構(gòu)面為底滑面，NNE或NWW向陡傾斷層作為后緣拉裂面的組合塊體下滑力大，安全系數(shù)較低。由于右壩肩邊坡內(nèi)部緩傾角斷層性狀較差（多為泥型、夾泥型），且延伸長、埋深較大，邊坡的支護措施在采用傳統(tǒng)的預應力錨索為主對邊坡進行加固的同時，還應當采用混凝土抗剪洞置換結(jié)構(gòu)面軟弱物質(zhì)，提高緩傾角斷層力學性能，兩種有效支護措施結(jié)合對邊坡整體穩(wěn)定性進行控制；對于邊坡淺表部巖體以及隨機不穩(wěn)定塊體采用掛網(wǎng)噴漿及全長黏結(jié)砂漿錨桿加強支護，對規(guī)模相對較大的潛在不穩(wěn)定塊體主要采用預應力錨索支護。 （5）Midas數(shù)值計算結(jié)果表明，開挖后，坡體表面及坡腳處出現(xiàn)應力調(diào)整及應力集中現(xiàn)象，緩傾角斷層后緣附近出現(xiàn)較大范圍的拉應力區(qū)。伴隨緩傾角斷層切露，斷層處出現(xiàn)大水平位移；開挖后緩傾角結(jié)構(gòu)面上部巖體整體均表現(xiàn)出向臨空面的滑移變形，剪應變增量區(qū)域主要沿緩傾角斷層發(fā)展。在實施加固措施之后，fh01、fh02、fh03、fh04、fh05、fh06號緩傾角斷層附近的最大主應力及最大位移量顯著減小，邊坡表面應力在支護前后重新變得平滑且連續(xù)，指向工程邊坡臨空面的最大水平位移下降至毫米級別。同時，混凝土抗剪洞的布置中斷剪應力增量集中區(qū)的貫通，表明工程采用的一系列支護措施對邊坡的加固有效，能夠較好的防止工程邊坡的失穩(wěn)破壞。
[Abstract]:The proposed two cascade hydropower station is the third cascade hydropower station planned in the middle reaches of the Yalong River. The maximum dam height of the gravity dam is 153m, the height of the right abutment slope is nearly 210m, the maximum excavation depth is near 100m. slope fracture, the cracks are developed and the geological conditions are complex, especially the control of a group of gently sloping small faults and fractured zones, and the slope deformation is strong. The shallow rock mass is relaxed and cracked, and the stability is poor. There is a great safety hazard in the excavation slope. Therefore, it is of great practical significance to study the stability of the right abutment slope and put forward the corresponding support measures to ensure the safety of the construction.
In this paper, on the basis of geological environment conditions, rock mass structure and deformation fracture characteristics, the concept model of slope deformation and failure mechanism is established, and the stability of slope is analyzed synthetically by geological analysis, rigid body limit equilibrium method and numerical calculation method, and then the preliminary support design scheme of Engineering Slope is put forward. The following main points are obtained. Achievements.
(1) the slope lithology is the early Yanshan black cloud two long granite, which is characterized by the development of NW to gentle dip angle structure. The fh01, fh02, fh03, fh04, fh05, and fh06 long dip angle faults in the slope are controlled by the slope stability. In addition, the steep dip and NWW-EW steep dip two steep dip angles are developed. The rock structure is controlled by the rock mass structure. The rock slope rock generally has creeping and splitting deformation along the slow dip fault, the maximum slip deformation can reach more than 5m (PD53 adit f5303). The rock weathering and unloading is strong, the level depth of the strong unloading can reach 108m, the maximum horizontal depth of the weak unloading can reach 153m..
(2) the slope of the engineering slope is controlled by NW to slow dip angle structure surface, and its deformation and failure mode is a series of slippery.Fh01, fh02, fh03, fh04, fh05, fh06 and a series of gentle dip faults as the bottom sliding surface, with NNE or NWW to the steep dip fault as the back edge crack surface, and Henghe to the steep steep fault is a lateral cutting surface.
(3) the stability evaluation results show that the overall stability of the right abutment slope is controlled by the fh06+f53 composite block. The large combination block of fh01+f53, fh02+f53, fh03+f53, fh04+f53 and fh05+f53 also has great influence on the overall stability of the slope. The stability coefficient of fh03+f53, fh04+f53 and fh04+f555 is between 0.865-0.901 and the whole slope of the slope under the natural condition. In the unstable state, the local stability coefficient of fh03+f53, fh04+f53 composite block is the lowest, between 0.865 and 0.889.Fh01+f53, fh02+f53, fh05+f53 block combination stability coefficient is between 0.954-1.033, the whole slope is in the limit equilibrium state. Under heavy rain and earthquake conditions, fh01+f53, fh02+f53, fh03+f53, fh04+f53, fh05+f53, fh06 The stability coefficient of +f53 block is less than 0.95, and the slope is unstable.
(4) according to the results of stability evaluation, the corresponding supporting measures are put forward for different parts of the right abutment slope. The design of slope reinforcement should be carried out according to the prudent excavation, reducing blasting and subregional hierarchical support, and taking the overall stability control of the slope as the primary problem in the design of slope support measures. The stability of the right abutment slope is controlled by the typical controlled gentle dip slope structure. After the excavation of the slope, the surface of the slope is cut out of the surface, which seriously affects the safety of the engineering. The result of the slope sliding force calculation shows that the gentle dip structure surface is a bottom sliding surface, and the NNE or NWW to the steep dip fault as the rear edge pull. The combination block of the split surface has a large sliding force and a lower safety factor. Due to the poor inclination of the slope in the right abutment slope (mostly mud and mud type), and lengthening and burial depth, the supporting measures of the slope are mainly reinforced by the traditional prestressed anchorage cable, while the concrete shear hole replacement structure surface should be adopted. The soft material can improve the mechanical properties of the slow dip fault, and the two effective supporting measures combine to control the overall stability of the slope; for the rock mass and the random unstable block of the slope, the hanging net spray and the full length cohesive mortar bolt are used to strengthen the support, and the prestressing anchor is mainly used for the relatively large potential unstable blocks. Cable support.
(5) the results of Midas numerical calculation show that after the excavation, the stress adjustment and stress concentration appear on the surface of the slope and the foot of the slope, and there is a large tensile stress zone near the back edge of the slow dip fault. With the slow dip angle fault exposure, the large horizontal displacement appears at the fault. After the implementation of the reinforcement measures, the maximum principal stress and maximum displacement of fh01, fh02, fh03, fh04, fh05 and fh06 are significantly reduced, and the surface stress of the slope becomes smooth and continuous before and after the support, pointing to the maximum water level on the surface of the engineering slope. The horizontal displacement is reduced to the millimeter level. At the same time, the concrete shear hole is arranged in the concentrated area of the shear stress increment, which indicates that a series of supporting measures adopted in the project are effective for the slope reinforcement and can better prevent the instability and failure of the slope.
【學位授予單位】：成都理工大學
【學位級別】：碩士
【學位授予年份】：2014
【分類號】：TV223

【參考文獻】

相關期刊論文 前10條

1 方建瑞;朱合華;蔡永昌;;邊坡穩(wěn)定性研究方法與進展[J];地下空間與工程學報;2007年02期

2 高大水;國內(nèi)巖土預應力錨固技術應用及錨固技術參數(shù)統(tǒng)計[J];長江科學院院報;2004年06期

3 索海生;文峪河水庫左岸滑坡體加固預應力錨索設計[J];東北水利水電;2005年05期

4 黃潤秋;中國西南巖石高邊坡的主要特征及其演化[J];地球科學進展;2005年03期

5 黃潤秋;論中國西南地區(qū)水電開發(fā)工程地質(zhì)問題及其研究對策[J];地質(zhì)災害與環(huán)境保護;2002年01期

6 伍法權;;巖體工程地質(zhì)動力學基本原理[J];工程地質(zhì)學報;2011年03期

7 宋從軍,周德培;預應力錨索框架型地梁的內(nèi)力計算[J];公路;2004年07期

8 張玉浩,張立宏;邊坡穩(wěn)定性分析方法及其研究進展[J];廣西水利水電;2005年02期

9 詹興強;徐乾奇;張曦;;雅礱江某水電站導流洞進水口邊坡穩(wěn)定性研究[J];長春工程學院學報(自然科學版);2014年01期

10 沈良峰,廖繼原,張月龍;邊坡穩(wěn)定性分析評價方法研究及趨向[J];建筑科學;2004年06期

本文編號：2077519