【摘要】 运用ADINA软件中的Newmark直接积分法和Mohr-Coulomb弹塑性模型,计算了交叉隧道运行期,在不同地震动波和不同方向地震激励作用下,隧道顶部不同覆土厚度时动力响应规律;分析了衬砌厚度变化对隧道地震反应的影响。计算结果表明:垂直于隧道轴线方向的地震波对隧道结构影响最大,对于立体交叉隧道最大位移、最大加速度一般发生在上部隧道顶板中间位置处,而最大主压应力一般出现在隧道顶板与边墙连接处,这些部位是结构安全的关键点,设计时应重点关注;随着隧道顶部覆土厚度的增加结构相对位移、加速度和应力都有所增加,且位移和应力变化比加速度大,当覆土厚度增加到一定程度时,响应将基本趋于稳定;随着衬砌厚度的增加结构最大相对位移和应力逐渐减小,而加速度将逐渐增大,但减小和增大幅值随衬砌厚度增加而越来越小。更多还原

【Abstract】 Using the Newmark immediate integration in ADINA and Mohr- Coulomb elasto-plastic model,the dynamic response law of cross tunnels with different thickness of covering soil under the impact of various seismic wave and multi-directional seismic excitation is calculated,and the influence of the thickness of lining on the seismic response of tunnels is also analyzed. The calculation result shows that the seismic wave vertical to the axis of the tunnel has the most significant impact on the tunnel structure. Also,the maximum displacement and acceleration normally occur at the middle point of upper tunnels,and the maximum principal compressive stress usually appears at the juncture between the roof of the upper tunnel and the sidewall. Both these positions are critical to structural safety,which deserve special attention in design. Another conclusion is that the relative displacement and acceleration increase with the thickness of covering soil,and that the variation in displacement and stress is larger than that of the acceleration. The response,however,stabilizes as the thickness of covering soil reaches a certain level. The results also reveal that the maximum displacement and stress diminishes yet acceleration rises as the thickness of lining increases,but the amplitude,both in increase and in decrease,abates.更多还原