现代隧道技术
現代隧道技術
현대수도기술
MODERN TUNNELLING TECHNOLOGY
2014年
6期
41-49
,共9页
改进动力强度折减法%隧道%地震破坏机理%影响因素
改進動力彊度摺減法%隧道%地震破壞機理%影響因素
개진동력강도절감법%수도%지진파배궤리%영향인소
Improved dynamic strength reduction method%Tunnel%Seismic failure mechanism%Influence factor
文章分析了影响隧道在地震作用下破坏的因素,研究了不同围岩级别、不同跨度、不同结构形式和不同埋深等条件下隧道结构在地震中的破坏机理,分别针对各个影响因素进行了对比分析;通过静动力转换边界将静力场施加到动力计算中作为初始应力条件,对动力强度折减法进行了改进,通过计算应用证明了其可行性;使用改进的动力强度折减法对深、浅埋隧道在地震作用下的破坏机理进行了计算分析。结果表明,不同埋深隧道在地震中的破坏过程不同,浅埋隧道是从隧道上方两侧开始破坏的,逐渐形成贯通到地面的破裂面;深埋隧道最先在4个边角的应力集中处出现塑性应变,顶部和底部的塑性应变较小,随后从两侧开始逐渐形成贯通的塑性应变区,直至破坏。
文章分析瞭影響隧道在地震作用下破壞的因素,研究瞭不同圍巖級彆、不同跨度、不同結構形式和不同埋深等條件下隧道結構在地震中的破壞機理,分彆針對各箇影響因素進行瞭對比分析;通過靜動力轉換邊界將靜力場施加到動力計算中作為初始應力條件,對動力彊度摺減法進行瞭改進,通過計算應用證明瞭其可行性;使用改進的動力彊度摺減法對深、淺埋隧道在地震作用下的破壞機理進行瞭計算分析。結果錶明,不同埋深隧道在地震中的破壞過程不同,淺埋隧道是從隧道上方兩側開始破壞的,逐漸形成貫通到地麵的破裂麵;深埋隧道最先在4箇邊角的應力集中處齣現塑性應變,頂部和底部的塑性應變較小,隨後從兩側開始逐漸形成貫通的塑性應變區,直至破壞。
문장분석료영향수도재지진작용하파배적인소,연구료불동위암급별、불동과도、불동결구형식화불동매심등조건하수도결구재지진중적파배궤리,분별침대각개영향인소진행료대비분석;통과정동력전환변계장정력장시가도동력계산중작위초시응력조건,대동력강도절감법진행료개진,통과계산응용증명료기가행성;사용개진적동력강도절감법대심、천매수도재지진작용하적파배궤리진행료계산분석。결과표명,불동매심수도재지진중적파배과정불동,천매수도시종수도상방량측개시파배적,축점형성관통도지면적파렬면;심매수도최선재4개변각적응력집중처출현소성응변,정부화저부적소성응변교소,수후종량측개시축점형성관통적소성응변구,직지파배。
To explore the failure mechanism of tunnel structures in earthquakes, a static field was imposed to dy-namic calculation by shifting the boundary between static and dynamic, which was taken as an initial stress con-dition for the improvement of the dynamic strength reduction method, the feasibility of which was proven by a computing application. The improved dynamic strength reduction method is used to calculate and analyze the failure mechanism of deep and shallow buried tunnels under seismic action, and the results show that failure pro-cesses are different for tunnels with different depths. For the shallow-buried tunnel, failure begins at the two sides above the tunnel and gradually forms a fracture plane cutting through the ground; for the deep tunnel, the plastic strain first occurs at four stress-concentrated corners with a smaller plastic strain on the crown and floor, and then a continuous plastic strain zone is formed gradually from the two sides until failure finally occurs. In light of seismic action, this paper analyzes the factors affecting tunnel failure, studies the failure mechanism of tunnel structures of different surrounding rock grades, spans, structure types, and buried depths, and finally car-ries on a comparative analysis for each influence factor.