文档介绍：岩溶区围岩与隧道初期支护结构相互作用研究摘要本文以广西区钦崇高速公路路河山隧道为工程背景,采用理论分析、数值模拟结合现场试验等方法对岩溶区隧道围岩与初期支护结构相互作用进行了研究,并分析了隧道衬砌水压力对围岩及支护结构的影响,主要研究内容如下: (1)阐述了隧道围岩渗流场与应力场的相互作用原理,分别推导了不考虑渗流及考虑流固耦合情况下围岩应力与变形计算公式。(2)论述了支护结构作用机理,运用推导的公式结合路河山隧道实际绘制了围岩收敛曲线与支护抗力曲线。(3)运用MIDAS/GTS建立了路河山隧道二维模型,对比不施作支护结构与施作支护结构后围岩位移的变形及塑性区的发展,表明支护结构可明显的限制围岩的变形,延缓塑性区的发展;并进行了渗流一应力耦合模拟, 分析了渗流对围岩应力、位移、塑性区及锚杆应力、喷射混凝土应力的影响,结果表明渗流增大了围岩应力、位移,扩大了围岩塑性区的范围。通过施加不同大小的衬砌外水压力,表明衬砌外水压力对围岩及支护结构有着较大的影响。最后运用荷载释放系数法分别绘制了不考虑渗流与考虑渗流情况下围岩收敛曲线,考虑渗流作用时曲线有向右移动的趋势,这表明在同样的荷载释放系数下,考虑水的渗流作用时,围岩的位移有增大的趋; 发生相同位移时,所需的支护力也增大。(4)对路河山隧道进行监控量测,采集拱顶位移、锚杆应力、喷射混凝土应力并与理论解、数值解进行对比,结果表明以上各值大于不考虑渗流情况下的数值解,介于考虑渗流但不考虑外水压力与考虑渗流且考虑全部外水压力情况数值解之间,为“堵水限排’’提供一定理论基础。关键词:岩溶流固耦合相互作用特征曲线衬砌水压力 THE INTERACTION RESEARCH OF KARST AREA SI刀RRoUUD矾G RoCK ANDTl皿TI"眦L lMTIAL SUPPoRT STRUCTURE ABSTRACT Based on theLuheshan tunnel ofQin Chong freeway,this paper investigates interactionbetween surrounding rockandsupport ofkarst area tunnel,adopting numerical simulation withfieldtests,and analyzes thathydraulic pressure upon lining inkarst area have influence on surrounding rock and support structure. The main research contents areas follows: (1)The principle ofinteractionbetween seepage field and stressfieldof tunnel surrounding rock have been expatiated,derivating rock stress and deformation formula when taking consideration ofseepage and not. (2)The mechanism ofsupport structure havebeene)【patiatied,drawing the rockconvergence curve and support resistance curve theoretically withdeduced formula andLuheshan tunnel. (3)Thetwo dimension model ofLuheshan tunnelhave been established by MIDAS/paring the development ofplastic zone and the rock displacements when applie tosupporting structure ornot,show thatSupporting structure can be obvious limitation thedeformation ofthe surrounding rock, delay thedevelopment ofplasticzone;simulating seepage and stress coupling, Ⅲ analysis oftheimpact seepage on surrounding rockstress,displacement,plastic zone,bolt stress,shotcrete are thatth