本文選題：懸臂式擋土墻 + 極限狀態(tài)　； 參考：《太原理工大學(xué)》2017年碩士論文

【摘要】：懸臂式擋土墻是擋土墻的一種,其結(jié)構(gòu)簡單,自重較輕,施工方便,且便于工廠化生產(chǎn),經(jīng)濟(jì)性較好,被廣泛用于河道治理、道路建設(shè)、園林改造等眾多工程中,是近年來國內(nèi)常見的輕型擋土建筑物。合理地確定土壓力是懸臂式擋土墻設(shè)計(jì)的關(guān)鍵內(nèi)容,通常是將墻踵與墻頂?shù)倪B線或者將過墻踵的垂直面作為假想墻背,再根據(jù)朗肯理論或庫倫理論計(jì)算作用在假想墻背上的土壓力。該方法忽略了懸臂式擋土墻墻后填土中產(chǎn)生的破裂面,因此導(dǎo)致其與實(shí)際情況相差較大。本文運(yùn)用ANSYS有限元分析軟件建立懸臂式擋土墻、墻后土體及地基的彈塑性有限元模型,采用分段位移約束和接觸分析,通過尋找主動極限狀態(tài)下第一、二破裂面的位置,研究懸臂式擋土墻在極限狀態(tài)下主動土壓力的分布規(guī)律及影響因素。主要結(jié)論如下:(1)懸臂式擋土墻達(dá)到主動極限狀態(tài),填土中產(chǎn)生第一破裂面和第二破裂面。第一、二破裂面由墻踵附近出現(xiàn),分別向遠(yuǎn)離墻體和靠近墻立板的方向,經(jīng)填土內(nèi)部穿過,呈“V”型貫通。第二破裂面是懸臂式擋土墻固有的特征,并使墻踵板上方的部分填土因墻板保護(hù)而免受剪切破壞,在懸臂式擋土墻位移時(shí)隨墻體一起移動。根據(jù)懸臂式擋土墻幾何尺寸的不同,第二破裂面分為不與墻立板相交的直線形第二破裂面和與墻立板相交的折線形第二破裂面兩種。出現(xiàn)折線形第二破裂面且填土內(nèi)摩擦角和粘聚力較小時(shí),填土中出現(xiàn)平行于第一破裂面且與第二破裂面相交的第三破裂面。(2)填土內(nèi)摩擦角和粘聚力是土體的抗剪強(qiáng)度指標(biāo),內(nèi)摩擦角、粘聚力越大,土體抗剪切破壞能力越強(qiáng),達(dá)到主動極限狀態(tài)所需的墻體位移量也越大。墻體位移一定時(shí),土體發(fā)生塑性變形區(qū)域隨內(nèi)摩擦角和粘聚力的增大而減小。填土表面傾角對第二破裂面影響較小,對第一破裂面影響明顯。填土表面傾角越大,達(dá)到極限狀態(tài)所需的墻體位移量越大,第一破裂面塑性貫通區(qū)域越大,即參與破壞的土體量越多。(3)出現(xiàn)折線形第二破裂面,破裂面與墻體間的土體受到“保護(hù)”不發(fā)生剪切破壞。當(dāng)墻體移動時(shí),這些土體會與墻體一起移動,可視為墻體的一部分,故作用于折線形第二破裂面上的應(yīng)力即為懸臂式擋土墻土壓力,作用于第二破裂面上的水平土壓力隨填土內(nèi)摩擦角、粘聚力、彈性模量的增大而減小�？拷鼔︴嗵�,地基摩擦力影響明顯,水平土壓力有逐漸減小的趨勢。折線形破裂面上的垂直土壓力隨破裂面上方土體體積的增大而增大,填土內(nèi)摩擦角、粘聚力、彈性模量對其影響較小;出現(xiàn)直線形第二破裂面(第二破裂面在墻踵和墻頂連線的外側(cè))時(shí),第二破裂面與墻體之間的土體并不是全部隨著墻體運(yùn)動,因此不能簡單以直線形第二破裂面上的力近似為擋土墻水平土壓力。(4)無論填土中產(chǎn)生折線形還是直線形第二破裂面,隨著內(nèi)摩擦角、粘聚力、彈性模量的逐漸增大,水平合力逐漸減小,而合力作用點(diǎn)高度有增大的趨勢。填土中出現(xiàn)直線形破裂面且內(nèi)摩擦角不同,合力作用點(diǎn)小于折線形第二破裂面的情況。(5)由實(shí)際算例表明,有限元法對一般規(guī)模的懸臂式擋土墻結(jié)構(gòu),在常用計(jì)算機(jī)上試算一次所需時(shí)間為6~15min,因此,采用有限元法模擬工程中的懸臂式擋土墻以驗(yàn)算其土壓力及穩(wěn)定性有良好的應(yīng)用前景,在設(shè)計(jì)人員中推廣有限元原理、方法及軟件的應(yīng)用,用有限元軟件建模進(jìn)而驗(yàn)算其土壓力及穩(wěn)定性有重要意義。
[Abstract]:Cantilever retaining wall is a kind of retaining wall. It is simple in structure, light in weight, convenient in construction, easy to be produced in the factory and good in economy. It is widely used in many projects such as river management, road construction and garden reconstruction. It is a common lightweight retaining wall in China in recent years. It is reasonable to determine the earth pressure as a cantilever retaining wall. The key content is to connect the heel to the top of the wall or the vertical surface of the heel as the back of the imaginary wall, and then calculate the earth pressure on the back of the imaginary wall according to the Rankine theory or the Kulun theory. This method ignores the fracture surface in the backfill of the cantilever retaining wall, so it is quite different from the actual situation. The finite element analysis software ANSYS is used to set up the cantilever retaining wall and the elastoplastic finite element model of the soil and the foundation after the wall. By subsection displacement constraint and contact analysis, the distribution law of the active earth pressure and the influencing factors of the cantilever retaining wall under the limit state are studied by finding the position of the first, second fracture surface under the active limit state. The conclusions are as follows: (1) the cantilever retaining wall reaches the active limit state, the first fracture surface and the second fracture surface are produced in the fill. First, second the rupture surface appears near the wall heel, respectively, to the direction of the wall and the wall near the wall, passing through the fill, and the "V" type through. Second fracture surface is the inherent characteristic of the cantilever retaining wall, and makes the fracture surface a characteristic of the cantilever retaining wall. The partial fill above the wall heel is protected by the wall plate from shear failure and moves along with the wall when the cantilever retaining wall is displaced. According to the different geometric dimensions of the cantilever retaining wall, the second fracture surface is divided into two kinds of fracture surfaces that are not intersected with the wall of the wall and two of the broken line second fracture surfaces intersecting with the wall stand plate. The linear second fracture surface and the inner friction angle and cohesion of the fill are small, and the third fracture surface which is parallel to the first fracture surface and intersected with the second fracture surface. (2) the friction angle and cohesion of the fill are the shear strength index of the soil, the greater the internal friction angle, the greater the cohesive force, the stronger the shear failure ability of the soil, to the active limit shape. When the wall displacement is certain, the plastic deformation area of the soil decreases with the increase of internal friction angle and cohesive force. The inclination of the fill surface has little influence on the second fracture surface, and it has obvious influence on the first fracture surface. The greater the surface angle of the fill surface is, the greater the displacement of the wall is needed to reach the limit state, the first break. The larger the fractured surface plastic penetration area is, the more soil mass is involved. (3) there is a broken line second fracture surface, and the soil between the wall and the wall is protected from shear failure. When the wall moves, the soil will move with the wall, which can be seen as a part of the wall, so it should be used on the fractured surface of the second fracture surface. The force is the earth pressure of the cantilever retaining wall. The horizontal earth pressure on the second fracture surface decreases with the increase of the friction angle, cohesion and modulus of elasticity in the fill. The friction force of the foundation is obviously influenced by the wall near the wall, and the horizontal earth pressure gradually decreases. The vertical earth pressure above the fracture surface is with the volume of soil above the fracture surface. The friction angle, cohesive force and elastic modulus of the fill are less affected by the increase, and the soil between the second fracture surface and the wall is not all along with the wall when the linear second fracture surface (second fracture surface is on the side of the wall and the top of the wall) is not as simple as the force on the straight line second fracture surface. Horizontal earth pressure of retaining wall. (4) no matter the folding or linear second fracture surface in the fill, with the internal friction angle, cohesive force and modulus of elasticity gradually increasing, the horizontal resultant force gradually decreases, and the point of the resultant force is increased. There is a straight fracture surface in the fill and the internal friction angle is different, and the point of action is less than the fold line. Second the case of fracture surface. (5) the actual calculation shows that the time required for the finite element method to test the cantilever retaining wall structure of the general scale is 6~15min. Therefore, the finite element method is used to simulate the cantilever retaining wall in the project to check the earth pressure and stability. It is of great significance to popularize the principles, methods and software applications of finite element method, and use finite element software modeling to check its earth pressure and stability.

【學(xué)位授予單位】：太原理工大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2017
【分類號】：TU476.4

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 楊國清;;基于有限元法的懸臂式擋土墻墻頂變形影響因素分析[J];路基工程;2015年05期

2 劉春梅;李軍;;宋集屯水庫溢洪道尾水渠衡重式擋土墻設(shè)計(jì)[J];黑龍江水利;2015年10期

3 徐楊;閻長虹;姜玉平;許寶田;;滑裂面形狀對擋土墻主動土壓力的影響[J];煤田地質(zhì)與勘探;2015年04期

4 魏歡;張文龍;許茂坤;盧宏飛;;墻后三角形填土主動土壓力理論計(jì)算研究[J];地下空間與工程學(xué)報(bào);2015年S1期

5 施小平;;懸臂式擋土墻抗滑穩(wěn)定性分析[J];南水北調(diào)與水利科技;2015年01期

6 孫鍵;洪寶寧;劉鑫;栗金文;;基于粘聚力與摩擦角的路堤邊坡穩(wěn)定性敏感分析[J];水利與建筑工程學(xué)報(bào);2013年06期

7 王景環(huán);盧義玉;郭建強(qiáng);杜鵬;黃輝;;二級新型懸臂式擋土墻主動土壓力計(jì)算方法[J];煤炭學(xué)報(bào);2013年S1期

8 王奎華;馬少俊;吳文兵;;擋土墻后曲面滑裂面下黏性土主動土壓力計(jì)算[J];西南交通大學(xué)學(xué)報(bào);2011年05期

9 李英杰;;懸臂式擋土墻的設(shè)計(jì)[J];工程建設(shè)與設(shè)計(jì);2010年07期

10 王景環(huán);傅紹娟;;二級新型懸臂式擋土墻有限元分析[J];山西建筑;2010年13期

相關(guān)會議論文 前1條

1 魏歡;張文龍;許茂坤;盧宏飛;;墻后三角形填土主動土壓力理論計(jì)算研究[A];中國土木工程學(xué)會第十二屆全國土力學(xué)及巖土工程學(xué)術(shù)大會論文摘要集[C];2015年

相關(guān)碩士學(xué)位論文 前4條

1 王河;繞墻底轉(zhuǎn)動擋土墻非極限狀態(tài)主動土壓力研究[D];太原理工大學(xué);2016年

2 王婭娜;懸臂式擋土墻力學(xué)特性及結(jié)構(gòu)優(yōu)化研究[D];西南交通大學(xué);2015年

3 張勇;懸臂式擋土墻土壓力研究[D];太原理工大學(xué);2013年

4 鐘智勇;粘性填土重力式擋墻土壓力計(jì)算方法研究[D];長沙理工大學(xué);2007年

，

本文編號：1793721