长江科学院院报
長江科學院院報
장강과학원원보
JOURNAL OF YANGTZE RIVER SCIENTIFIC RESEARCH INSTITUTE
2015年
5期
121-126
,共6页
凌飞%肖宏跃%朱夏乐%雷宛%蒋亚东
凌飛%肖宏躍%硃夏樂%雷宛%蔣亞東
릉비%초굉약%주하악%뢰완%장아동
黏弹性介质%隧道地震%交错网格%开挖损伤带%波场模拟
黏彈性介質%隧道地震%交錯網格%開挖損傷帶%波場模擬
점탄성개질%수도지진%교착망격%개알손상대%파장모의
viscoelastic medium%tunnel seismic%staggered grid%excavation damaged zone%wave field simulation
针对隧道中各种不良地质体的超前预报问题,以黏弹性介质为基础,在空气隧道周围添加一定厚度的开挖损伤带,建立符合实际情况的观测系统,通过交错网格有限差分正演,模拟地震波在断层、软弱夹层、溶洞等地质灾害体模型中的传播,根据不同时刻的波场快照来研究相应地质模型地震记录的响应特征。通过对隧道地震二维波场模拟结果进行分析,研究结果表明:对一阶速度-应力黏弹性波动方程,采用交错网格有限差分,并且对隧道添加约束条件,可以快速、有效地实现隧道地震的二维正演模拟,并且波场快照能够清楚地反映地震波在不同地质模型中的传播特征以及波的转换特征,地震记录能够反映不同地质模型的地震响应特征,可以为实际隧道超前预报提供理论依据。
針對隧道中各種不良地質體的超前預報問題,以黏彈性介質為基礎,在空氣隧道週圍添加一定厚度的開挖損傷帶,建立符閤實際情況的觀測繫統,通過交錯網格有限差分正縯,模擬地震波在斷層、軟弱夾層、溶洞等地質災害體模型中的傳播,根據不同時刻的波場快照來研究相應地質模型地震記錄的響應特徵。通過對隧道地震二維波場模擬結果進行分析,研究結果錶明:對一階速度-應力黏彈性波動方程,採用交錯網格有限差分,併且對隧道添加約束條件,可以快速、有效地實現隧道地震的二維正縯模擬,併且波場快照能夠清楚地反映地震波在不同地質模型中的傳播特徵以及波的轉換特徵,地震記錄能夠反映不同地質模型的地震響應特徵,可以為實際隧道超前預報提供理論依據。
침대수도중각충불량지질체적초전예보문제,이점탄성개질위기출,재공기수도주위첨가일정후도적개알손상대,건립부합실제정황적관측계통,통과교착망격유한차분정연,모의지진파재단층、연약협층、용동등지질재해체모형중적전파,근거불동시각적파장쾌조래연구상응지질모형지진기록적향응특정。통과대수도지진이유파장모의결과진행분석,연구결과표명:대일계속도-응력점탄성파동방정,채용교착망격유한차분,병차대수도첨가약속조건,가이쾌속、유효지실현수도지진적이유정연모의,병차파장쾌조능구청초지반영지진파재불동지질모형중적전파특정이급파적전환특정,지진기록능구반영불동지질모형적지진향응특정,가이위실제수도초전예보제공이론의거。
In view of the problems in advanced detection of defective geological structures in tunnel,a geological tunnel model was established based on viscoelastic medium to simulate the seismic wave propagation in fault,weak interlayer,karst cave and other geological hazard body.The tunnel is surrounded by the excavation damaged zone. A practical observation system and the staggered grid finite-difference method were employed for the simulation. According to the wave field snapshots at different instants,the response of seismic record acquired from the corre-sponding forward modelling was researched.Result shows that the two-dimensional forward simulation based on vis-coelastic medium can be achieved by using a staggered grid finite-difference algorithm and adding tunnel con-straints.The wave field snapshots could clearly reflect the seismic wave propagation and transformation in different geological models.The seismic record reflects the seismic response characteristics of different models,and offers a theoretical basis for the seismic prediction of actual tunnels.