基岩地震波作用下隧道计算模型分析

Analysis on Tunnel Models by Bedrock Seismic Waves

针对隧道的地震计算模型,详细分析了地震波、有限元区域及边界条件、有限单元尺寸等3个关键问题,指出:隧道的地震分析应采用平原基岩地震波;在地震波作用分析中计算模型应采用底部固定边界条件,侧面具有无限边界时,不宜采用有限截断后添加具有透射功能的边界,而宜根据圣维南原理采用大范围的截断边界;有限元尺寸应根据地震波的频谱关系确定。

Regarding the seismic calculation model of tunnels, three key issues, i. e. , the seismic waves, the finite ele- ment region and boundary condition and the finite element size, are analyzed in detail in this paper. The following conclusions are drawn： plain bedrock seismic wave should be used in seismic analysis of tunnels; bottom-fixed boundary conditions should be adopted in the calculation model of the seismic analysis; instead of boundaries that have transmis- sion functions after finite truncation, large scale truncation boundaries should be adopted based on Saint-Venant＇s principle in case of infinite boundaries on the side; the finite element size should be determined in accordance with the spectrum of seismic waves.