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

【摘要】：擬建牙根二級(jí)水電站是雅礱江中游規(guī)劃的第三個(gè)梯級(jí)電站，設(shè)計(jì)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(fù)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(qiáng)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(jìn)而提出相應(yīng)的支護(hù)措施建議，對(duì)確保工程施工安全具有重要的實(shí)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(chǔ)上，建立邊坡變形破壞機(jī)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(jì)算方法綜合分析邊坡穩(wěn)定性，進(jìn)而提出工程邊坡初步支護(hù)設(shè)計(jì)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(zhǎng)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(zhǎng)大緩傾角斷層對(duì)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(dá)5m以上（PD53平硐f5303）。巖體風(fēng)化卸荷強(qiáng)烈，強(qiáng)卸荷水平深度可達(dá)108m，，弱卸荷最大水平深度可達(dá)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(zhǎng)大斷層則構(gòu)成側(cè)向割裂面。 （3）穩(wěn)定性評(píng)價(jià)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(duì)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(píng)價(jià)結(jié)果，對(duì)右壩肩邊坡不同部位提出了相應(yīng)的支護(hù)措施。邊坡加固設(shè)計(jì)應(yīng)按照謹(jǐn)慎開挖、減少爆破、分區(qū)域分層次支護(hù)的原則進(jìn)行，將工程邊坡的整體穩(wěn)定性控制作為邊坡支護(hù)措施設(shè)計(jì)的首要問(wèn)題，穩(wěn)定性的控制秉從先整體后局部順序進(jìn)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(yán)重影響工程安全性；經(jīng)邊坡下滑力計(jì)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(zhǎng)、埋深較大，邊坡的支護(hù)措施在采用傳統(tǒng)的預(yù)應(yīng)力錨索為主對(duì)邊坡進(jìn)行加固的同時(shí)，還應(yīng)當(dāng)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(xué)性能，兩種有效支護(hù)措施結(jié)合對(duì)邊坡整體穩(wěn)定性進(jìn)行控制；對(duì)于邊坡淺表部巖體以及隨機(jī)不穩(wěn)定塊體采用掛網(wǎng)噴漿及全長(zhǎng)黏結(jié)砂漿錨桿加強(qiáng)支護(hù)，對(duì)規(guī)模相對(duì)較大的潛在不穩(wěn)定塊體主要采用預(yù)應(yīng)力錨索支護(hù)。 （5）Midas數(shù)值計(jì)算結(jié)果表明，開挖后，坡體表面及坡腳處出現(xiàn)應(yīng)力調(diào)整及應(yīng)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(yīng)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(yīng)變?cè)隽繀^(qū)域主要沿緩傾角斷層發(fā)展。在實(shí)施加固措施之后，fh01、fh02、fh03、fh04、fh05、fh06號(hào)緩傾角斷層附近的最大主應(yīng)力及最大位移量顯著減小，邊坡表面應(yīng)力在支護(hù)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(jí)別。同時(shí)，混凝土抗剪洞的布置中斷剪應(yīng)力增量集中區(qū)的貫通，表明工程采用的一系列支護(hù)措施對(duì)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(xué)位授予單位】：成都理工大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2014
【分類號(hào)】：TV223

【參考文獻(xiàn)】

相關(guān)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(jìn)展[J];地下空間與工程學(xué)報(bào);2007年02期

2 高大水;國(guó)內(nèi)巖土預(yù)應(yīng)力錨固技術(shù)應(yīng)用及錨固技術(shù)參數(shù)統(tǒng)計(jì)[J];長(zhǎng)江科學(xué)院院報(bào);2004年06期

3 索海生;文峪河水庫(kù)左岸滑坡體加固預(yù)應(yīng)力錨索設(shè)計(jì)[J];東北水利水電;2005年05期

4 黃潤(rùn)秋;中國(guó)西南巖石高邊坡的主要特征及其演化[J];地球科學(xué)進(jìn)展;2005年03期

5 黃潤(rùn)秋;論中國(guó)西南地區(qū)水電開發(fā)工程地質(zhì)問(wèn)題及其研究對(duì)策[J];地質(zhì)災(zāi)害與環(huán)境保護(hù);2002年01期

6 伍法權(quán);;巖體工程地質(zhì)動(dòng)力學(xué)基本原理[J];工程地質(zhì)學(xué)報(bào);2011年03期

7 宋從軍,周德培;預(yù)應(yīng)力錨索框架型地梁的內(nèi)力計(jì)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(jìn)展[J];廣西水利水電;2005年02期

9 詹興強(qiáng);徐乾奇;張曦;;雅礱江某水電站導(dǎo)流洞進(jìn)水口邊坡穩(wěn)定性研究[J];長(zhǎng)春工程學(xué)院學(xué)報(bào)(自然科學(xué)版);2014年01期

10 沈良峰,廖繼原,張?jiān)慢?邊坡穩(wěn)定性分析評(píng)價(jià)方法研究及趨向[J];建筑科學(xué);2004年06期

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