本文關(guān)鍵詞： 盾構(gòu)襯砌 管片接頭 三維非連續(xù)接觸模型 靜動力分析 側(cè)向卸載 多尺度混合建模技術(shù)　出處：《中南大學(xué)》2014年碩士論文　論文類型：學(xué)位論文

【摘要】：盾構(gòu)隧道襯砌的最重要特征是采用管片拼裝而成,而接頭結(jié)構(gòu)的存在使得盾構(gòu)襯砌在受力與變形方面與一般整體式隧道襯砌存在顯著差異,尤其在列車荷載的反復(fù)作用下,管片接頭結(jié)構(gòu)常常發(fā)展為隧道的病害多發(fā)點。 本論文以國家重點基礎(chǔ)研究發(fā)展計劃項目(2011CB013802)等課題為依托,采用數(shù)值計算方法系統(tǒng)研究正常服役及鄰近基坑開挖卸載條件下的地鐵盾構(gòu)管片與接頭結(jié)構(gòu)靜動力特性。主要內(nèi)容和結(jié)論如下： (1)充分考慮盾構(gòu)隧道結(jié)構(gòu)特征,運用非線性接觸理論,模擬管片接頭結(jié)構(gòu)和管片襯砌與圍巖及道床之間的相互作用,建立道床-管片-圍巖的三維非連續(xù)接觸模型,并通過引入無限元靜動力人工邊界及列車動力荷載,使模型可以在靜力計算的應(yīng)力應(yīng)變基礎(chǔ)上進行列車荷載作用下的隧道動力響應(yīng)分析。 (2)基于道床-管片-圍巖的三維非連續(xù)接觸模型,對盾構(gòu)管片與接頭結(jié)構(gòu)在圍巖靜壓及列車動載作用下的受力與變形進行了分析,得到了管片接頭結(jié)構(gòu)的變形、應(yīng)力、接頭螺栓內(nèi)力在列車動載作用下的變化規(guī)律。 (3)結(jié)合多尺度混合建模技術(shù),研究鄰近基坑開挖過程中盾構(gòu)管片與接頭結(jié)構(gòu)的受力變形規(guī)律及控制指標。隨著鄰近基坑開挖,管片與接頭結(jié)構(gòu)的應(yīng)力和變形均大幅增加,且當襯砌豎向收斂率大于3.68‰,軸線水平偏移率大于0.53‰時,應(yīng)對盾構(gòu)隧道性態(tài)進行特別關(guān)注,部分接頭變形、接頭處混凝土應(yīng)力、接頭螺栓內(nèi)力已經(jīng)達到使用極限。 (4)研究了鄰近基坑開挖卸載對管片與接頭結(jié)構(gòu)動力特性的影響。側(cè)向卸載前后結(jié)構(gòu)的動力響應(yīng)時程曲線變化規(guī)律一致,但側(cè)向卸載使隧道的動力響應(yīng)有所增大,且靠近基坑一側(cè)的接頭結(jié)構(gòu)動力響應(yīng)增大最多。
[Abstract]:The most important feature of shield tunnel lining is that the pipe piece is assembled , and the existence of the joint structure makes the shield lining significantly different from the general one - piece tunnel lining in the aspects of stress and deformation , especially under the repeated action of train load . Based on the research and development plan project of the national key basic research and development plan project ( 2011CB13802 ) , this paper uses numerical calculation method to study the static dynamic characteristics of metro shield segments and joint structures under normal service and adjacent excavation unloading conditions . The main contents and conclusions are as follows : ( 1 ) taking fully into account the structural features of shield tunnel , using nonlinear contact theory , simulating interaction between pipe joint structure and pipe piece lining and surrounding rock and ballast bed , establishing three - dimensional non - continuous contact model of ballast bed - tube sheet - surrounding rock , and introducing infinite element static power artificial boundary and train dynamic load , so that the model can carry out tunnel dynamic response analysis under the action of train load on the basis of stress strain calculated by static force . ( 2 ) Based on the three - dimensional discontinuous contact model of bed - tube - surrounding rock , the stress and deformation of shield segment and joint structure under the action of static pressure of surrounding rock and dynamic load of train are analyzed , and the rule of deformation , stress and internal force of joint bolt under the action of train dynamic load is obtained . ( 3 ) Combined with multi - scale hybrid modeling technology , the stress deformation law and control index of shield tube sheet and joint structure in excavation of adjacent foundation pit are studied . As the vertical convergence rate of adjacent foundation pit is greater than 3.68 鈥，

本文編號：1475944