摘要
利用轴对称线弹性模型有限元方法,计算了洞室中温度微小年变化引起的地倾斜和地应变.结果表明,在满足地震台站建设规范的情况下(洞室内温度年变化幅度应小于等于0.5℃),当洞室中温度年变化幅度仅为0.2℃时,仍会引起量级为10-7rad的地倾斜和10-7的地应变,并且在洞室的尽头和拐弯处由于热汇聚和热扩散的作用引起地倾斜和地应变的变化更为突出.因此今后在观测中,有必要进一步减小洞室内温度年变化;在台站设计建设和仪器布设中,对基线式仪器和摆式仪器都可以做一些恰当考虑,以尽量压制温度年变化带来的影响.
In this paper, finite element method （FEM） of axisymmetric linear elastic model has been used to calculate the tilt and strain induced by small annual temperature variations in a deep tunnel. The results show that even if the amplitude of the annual variation meets the construction standard of seismic station issued by China Earthquake Administration （the annual temperature varia tion amplitude in the tunnel is no more than 0.5℃）, a small annual temperature variation of amplitude iust 0.2℃ in the tunnel would produce 10^-7 rad changes in tilt and 10^-7 changes in strain. Especially, at the end and the corner of the tunnel, changes of tilt and strain can he even larger. Therefore, in the future, it is an important task to reduce the annual temperature variation in the tunnel as far as possible. Within the tunnel, for both baseline instrument and pendulum instrument, the modeling suggests ways of construction of the tunnel and installation of the instrument to decrease the influence of the annual tempera- ture variation.
出处
《地震学报》
CSCD
北大核心
2008年第5期464-473,550,共10页
Acta Seismologica Sinica
基金
China Earthquake Administration Sector Fund (2008419077)
Knowledge Innovation Program of the Chinese Academy of Sciences (kzcx2-yw-123).
关键词
有限单元法
地倾斜
地应变
年变化
finite element method （FEM）
tilt
strain
annual variation
