本文選題：震源斷層 + 粘滑作用�。� 參考：《西南交通大學》2017年碩士論文

【摘要】：我國境內(nèi)具有復雜、活躍的板內(nèi)構(gòu)造,本地區(qū)地震活動大多與板內(nèi)的活動斷層有關(guān),其觸發(fā)機制多為地殼內(nèi)部震源斷層的粘滑行為。震源斷層發(fā)震時會造成地表巖土層沿斷層面產(chǎn)生脆性破裂形成地震斷層,長久以往近場區(qū)域還會伴有若干斷層、斷層破碎帶等特殊地質(zhì)構(gòu)造;另外,震害調(diào)研以及地震工程學研究成果反應近斷層地震動具有速度脈沖、豎向分量效應等特征,其對結(jié)構(gòu)物的影響明顯區(qū)別于遠場地震動。隨著各地建設規(guī)劃的實施,難免有地處震源斷層場地區(qū)域的隧道工程,因此對于近場區(qū)域的隧道結(jié)構(gòu)而言有不可小覷的安全隱患,本文便著手斷層粘滑作用下跨地震斷層公路隧道的破壞機理和近場地震動作用下穿越斷層破碎帶公路隧道的動力響應兩方面開展了如下工作:(1)以龍門山斷裂為背景,基于速率弱化摩擦本構(gòu)定義震源斷層非線性接觸關(guān)系,以模擬斷層粘滑時刻的破裂行為,并利用Burgers粘彈性本構(gòu)定義地殼巖石圈的流變屬性,通過施加板塊的擠壓(拉伸)速率進行逆斷層(正斷層)粘滑過程的數(shù)值模擬,同時對比計算了多種板塊運動速率下斷層產(chǎn)生粘滑作用的差異。其次,建立了水平面內(nèi)的走滑斷層數(shù)值計算模型,采用同樣的方法模擬走滑斷層的粘滑過程。最終,得到三種形式斷層粘滑作用時的關(guān)鍵參數(shù)特征曲線,作為下一步研究的基礎。(2)建立一正向穿越傾角60°地震斷層的公路隧道三維有限元模型,將(1)中獲得的斷層粘滑時刻上下盤的相對位移時程施加到三維計算模型中,通過擴展有限元理論獲得不同地層條件的逆斷層、正斷層、走滑斷層粘滑作用下襯砌開裂的力學行為和破壞機理。(3)建立賦存于近斷層場地、穿越斷層破碎帶隧道結(jié)構(gòu)三維有限元模型,定義混凝土結(jié)構(gòu)的彈塑性本構(gòu),對比相同峰值加速度的共4條近場、非近場地震波作用下隧道結(jié)構(gòu)的動力響應差異,以評價近斷層地震動的速度脈沖對穿越斷層破碎帶隧道的動力效應;保持水平向輸入集集地震波,定義豎向與水平向峰值向加速度比λ,對豎向地震分量作用下穿越斷層破碎帶隧道結(jié)構(gòu)的動力響應特征進行分析。
[Abstract]:There are complex and active intraplate structures in China. The seismic activities in this area are mostly related to the active faults in the plate, and the triggering mechanism is mostly the visco-slip behavior of the focal faults in the crust.When the source fault occurs, it will result in brittle rupture along the fault plane of the surface rock and soil layer to form an earthquake fault. In the past, there will also be some special geological structures, such as faults, fault fracture zones, etc. In the near field in the past,Seismic damage investigation and seismic engineering research results show that near-fault seismic response has the characteristics of velocity pulse and vertical component effect, and its influence on structure is obviously different from that of far-field ground motion.With the implementation of local construction planning, it is inevitable that there is a tunnel project located in the area of the focal fault site, so there is a potential safety hazard for the tunnel structure in the near-field area.In this paper, the failure mechanism of the cross-seismic highway tunnel under the action of slip and the dynamic response of the highway tunnel under near-field ground motion through the broken fault zone are discussed as follows: 1) taking the Longmenshan fault as the background,Based on the velocity weakening friction constitutive equation, the nonlinear contact relationship of the focal fault is defined to simulate the rupture behavior at the time of viscosity and slip of the fault, and the rheological properties of the crustal lithosphere are defined by using the Burgers viscoelastic constitutive equation.The viscous slip process of the reverse fault (normal fault) is simulated by applying the compression (tensile) rate of the plate, and the difference of the sticking-slip effect of the fault under various plate motion rates is compared and calculated.Secondly, the numerical model of strike-slip fault in horizontal plane is established, and the same method is used to simulate the stick-slip process of strike-slip fault.Finally, the key parameter characteristic curves of three types of fault stick-slip action are obtained. As the basis of further study, a 3-D finite element model of highway tunnel with forward crossing of 60 擄seismic fault is established.The relative displacement time history of the upper and lower displacements of the upper and lower displacements obtained from the slip time of the fault is applied to the three-dimensional computational model, and the reverse faults and normal faults with different formation conditions are obtained by extending the finite element theory.The mechanical behavior and failure mechanism of lining cracking under the action of stick-slip of strike-slip fault. (3) the three-dimensional finite element model of tunnel structure through fault fracture zone is established, and the elastic-plastic constitutive model of concrete structure is defined.The dynamic response of tunnel structure under the action of non-near-field seismic wave is compared with that of four near-field with the same peak acceleration to evaluate the dynamic effect of velocity pulse of near-fault ground earthquake on the tunnel through fault broken zone.The vertical and horizontal peak acceleration ratio 位 is defined and the dynamic response characteristics of the tunnel structure through the fault broken zone under the action of the vertical seismic component are analyzed by preserving the horizontal input collection of seismic waves and defining the ratio of vertical to horizontal peak acceleration.
【學位授予單位】：西南交通大學
【學位級別】：碩士
【學位授予年份】：2017
【分類號】：U451

【相似文獻】

相關(guān)期刊論文 前1條

1 吳立新,劉善軍,許向紅,吳育華,李永強;遙感-巖石力學(III)——交匯斷層粘滑的熱紅外輻射與聲發(fā)射規(guī)律及其構(gòu)造地震前兆意義[J];巖石力學與工程學報;2004年03期

相關(guān)碩士學位論文 前2條

1 丁梯;斷層粘滑及近場地震動作用下公路隧道結(jié)構(gòu)力學行為研究[D];西南交通大學;2017年

2 孫楠;用數(shù)值模擬方法研究不同因素對斷層粘滑運動的影響[D];云南大學;2013年

，

本文編號：1746910