【摘要】：四川西部地形復(fù)雜,地質(zhì)活躍,是我國(guó)地震災(zāi)害最嚴(yán)重的地區(qū)之一。這些地區(qū)高陡邊坡繁多,許多鐵路線(xiàn)路的橋梁的墩臺(tái)基礎(chǔ)不可避免的會(huì)設(shè)置于高陡邊坡及滑坡、巖堆等不良地質(zhì)體上。許多高陡邊坡在地震作用下極易發(fā)生滑坡,從而對(duì)邊坡上的鐵路橋梁樁基造成嚴(yán)重?fù)p害。因此,研究地震作用下陡坡橋梁樁基及其支護(hù)結(jié)構(gòu)地震響應(yīng)特征與結(jié)構(gòu)的內(nèi)力分布規(guī)律顯得尤為重要。論文針對(duì)高陡邊坡鐵路橋梁樁基及支護(hù)結(jié)構(gòu)在地震作用下的響應(yīng)特征及內(nèi)力分布問(wèn)題,以某鐵路線(xiàn)上某工點(diǎn)滑坡體的鐵路橋梁工程建設(shè)為背景,采用資料調(diào)研、振動(dòng)臺(tái)模型試驗(yàn)、FLAC3D數(shù)值模擬等方法,研究橋梁樁基及其支護(hù)結(jié)構(gòu)在地震作用下的動(dòng)力響應(yīng)特征及結(jié)構(gòu)的內(nèi)力分布規(guī)律。經(jīng)過(guò)研究,得到主要結(jié)論如下:(1)地震作用下,模型邊坡會(huì)發(fā)生剪切變形,從坡頂?shù)狡履_,沿水平方向上,由于抗滑樁的加固作用,各測(cè)點(diǎn)水平位移增量幅值越來(lái)越小;(2)地震作用下,動(dòng)力加速度響應(yīng)被邊坡放大,放大效應(yīng)隨高程增加越發(fā)明顯;加速度時(shí)程出現(xiàn)"滯后效應(yīng)"現(xiàn)象,較高位置點(diǎn)響應(yīng)滯后于較低位置點(diǎn);橋梁樁基及抗滑樁加固的臨近土體地震加速度響應(yīng)情況受到明顯抑制;(3)在基巖與滑體交界面附近,隨著地震荷載作用的增強(qiáng),考慮樁土相互作用下的橋梁樁基沿樁身自上而下的土壓力呈不規(guī)則分布,隨著埋深先增大后減小;抗滑樁樁背動(dòng)土壓力在滑動(dòng)面以下沿樁身逐漸變小,而在滑動(dòng)面以上沿樁身動(dòng)土壓力逐漸變大;隨著地震荷載的增大,抗滑樁樁后土體會(huì)產(chǎn)生一定的土抗力,樁身滑動(dòng)面以下部分可能會(huì)發(fā)生微小旋轉(zhuǎn)或者出現(xiàn)脫空現(xiàn)象,因此,工程設(shè)計(jì)中應(yīng)注意轉(zhuǎn)角的控制計(jì)算;(4)地震荷載作用下,由于抗滑樁對(duì)邊坡加固,橋梁樁基的彎矩整體相對(duì)較小,且從內(nèi)側(cè)樁基到外側(cè)樁基,同一高度處樁身彎矩越來(lái)越小;部分嵌固在基巖中的抗滑樁類(lèi)似于懸臂梁,內(nèi)力分布形式也近似,基巖以上抗滑部分的樁身彎矩隨高程的增加而減小;隨著地震荷載的增加,彎矩極值點(diǎn)附近樁身會(huì)發(fā)生塑性鉸破壞,因此抗震設(shè)計(jì)時(shí),應(yīng)該注意滑動(dòng)面處樁身的抗彎承載力的設(shè)計(jì)計(jì)算。
[Abstract]:The western part of Sichuan is one of the most serious areas of earthquake disaster because of its complex topography and active geology. There are many high and steep slopes in these areas, and the piers and abutments of many railway bridges will inevitably be set on high and steep slopes, landslides, rock piles and other bad geological bodies. Many high and steep slopes are prone to landslide under earthquake, which results in serious damage to the pile foundation of railway bridges on the slope. Therefore, it is very important to study the seismic response characteristics and internal force distribution of steep slope bridge pile foundation and its supporting structure. Aiming at the response characteristics and internal force distribution of pile foundation and supporting structure of railway bridge on high and steep slope under earthquake, the paper takes the railway bridge construction of a certain work point on a railway line as the background, adopts the data investigation. The dynamic response characteristics and internal force distribution of bridge pile foundation and its supporting structure under earthquake are studied by means of shaking table model test and FLAC3D numerical simulation. The main conclusions are as follows: (1) under earthquake, shear deformation will occur in the model slope, from the top to the foot of the slope, along the horizontal direction, because of the reinforcement effect of anti-slide pile, The increment amplitude of horizontal displacement is becoming smaller and smaller. (2) under the earthquake, the dynamic acceleration response is magnified by the slope, and the amplification effect becomes more and more obvious with the elevation increasing, and the acceleration time history appears the phenomenon of "lag effect". The response of the higher position point lags behind the lower position point; the seismic acceleration response of the bridge pile foundation and the adjacent soil strengthened by the anti-slide pile is obviously restrained; (3) near the interface between the bedrock and the sliding body, with the increase of the seismic load, Considering the pile-soil interaction, the earth pressure of bridge pile foundation is irregular distribution along the pile body from top to bottom, which increases first and then decreases with the depth of burying, and the dynamic earth pressure on the back of anti-slide pile decreases gradually along the pile body below the sliding surface. However, the dynamic earth pressure along the pile body increases gradually above the sliding surface, and with the increase of seismic load, the soil behind the anti-slide pile produces a certain soil resistance, and the slip surface of the pile body may rotate slightly or appear void phenomenon, so, In engineering design, attention should be paid to the calculation of the angle of rotation: (4) under the action of seismic load, the bending moment of bridge pile foundation is relatively small due to the reinforcement of slope by anti-slide pile, and the bending moment of pile body becomes smaller and smaller at the same height from the inside pile foundation to the outside pile foundation; The anti-slide pile embedded in the bedrock is similar to the cantilever beam, and the internal force distribution is similar. The bending moment of the anti-slide part above the bedrock decreases with the increase of elevation, and with the increase of seismic load, The plastic hinge failure will occur in the pile body near the moment extremum, so in seismic design, attention should be paid to the design and calculation of the flexural bearing capacity of the pile body at the sliding surface.
【學(xué)位授予單位】：西南交通大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2017
【分類(lèi)號(hào)】：U445.551

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 李明清;劉發(fā)明;;高烈度地震頻發(fā)山區(qū)泥石流對(duì)成蘭鐵路的影響和防治對(duì)策[J];高速鐵路技術(shù);2013年02期

2 葉海林;鄭穎人;李安洪;杜修力;;地震作用下邊坡抗滑樁振動(dòng)臺(tái)試驗(yàn)研究[J];巖土工程學(xué)報(bào);2012年02期

3 徐炳偉;姜忻良;;大型復(fù)雜結(jié)構(gòu)-樁-土振動(dòng)臺(tái)模型試驗(yàn)土箱設(shè)計(jì)[J];天津大學(xué)學(xué)報(bào);2010年10期

4 姚令侃;陳強(qiáng);;“5·12”汶川地震對(duì)線(xiàn)路工程抗震技術(shù)提出的新課題[J];四川大學(xué)學(xué)報(bào)(工程科學(xué)版);2009年03期

5 徐光興;姚令侃;李朝紅;高召寧;;邊坡地震動(dòng)力響應(yīng)規(guī)律及地震動(dòng)參數(shù)影響研究[J];巖土工程學(xué)報(bào);2008年06期

6 徐光興;姚令侃;高召寧;李朝紅;;邊坡動(dòng)力特性與動(dòng)力響應(yīng)的大型振動(dòng)臺(tái)模型試驗(yàn)研究[J];巖石力學(xué)與工程學(xué)報(bào);2008年03期

7 陳健瓊;李斌;伍海山;;土-樁-結(jié)構(gòu)動(dòng)力相互作用理論研究綜述[J];湖南城市學(xué)院學(xué)報(bào)(自然科學(xué)版);2006年03期

8 年廷凱,欒茂田,楊慶;阻滑樁加固土坡穩(wěn)定性分析與樁基的簡(jiǎn)化設(shè)計(jì)[J];巖石力學(xué)與工程學(xué)報(bào);2005年19期

9 凌賢長(zhǎng),王東升,王志強(qiáng),王成,王臣;液化場(chǎng)地樁-土-橋梁結(jié)構(gòu)動(dòng)力相互作用大型振動(dòng)臺(tái)模型試驗(yàn)研究[J];土木工程學(xué)報(bào);2004年11期

10 張建華,謝強(qiáng),張照秀;抗滑樁結(jié)構(gòu)的土拱效應(yīng)及其數(shù)值模擬[J];巖石力學(xué)與工程學(xué)報(bào);2004年04期

相關(guān)博士學(xué)位論文 前5條

1 張愛(ài)軍;擋土樁—土相互作用模型及抗滑樁加固邊坡簡(jiǎn)化計(jì)算方法研究[D];華南理工大學(xué);2013年

2 李雨潤(rùn);液化土層中樁基橫向動(dòng)力響應(yīng)研究[D];中國(guó)地震局工程力學(xué)研究所;2006年

3 孔德森;樁——土相互作用計(jì)算模型及其在樁基結(jié)構(gòu)抗震分析中的應(yīng)用[D];大連理工大學(xué);2004年

4 馮士倫;可液化土層中樁基橫向承載特性研究[D];天津大學(xué);2004年

5 肖曉春;地震作用下土—樁—結(jié)構(gòu)動(dòng)力相互作用的數(shù)值模擬[D];大連理工大學(xué);2003年

相關(guān)碩士學(xué)位論文 前2條

1 劉培玲;考慮土樁相互作用的高鐵橋梁抗震性能分析[D];北京交通大學(xué);2015年

2 宋保強(qiáng);抗滑樁支護(hù)結(jié)構(gòu)中樁后土拱效應(yīng)研究與應(yīng)用[D];成都理工大學(xué);2007年

，

本文編號(hào)：2192755