地震模拟振动台的数字仿真及其在龙江拱坝上的应用

Numerical simulation of shaking table and its application to Longjiang Arch Dam

通过对地震模拟振动台工作原理的模仿，用计算机技术实现了对地震模拟振动台的数字仿真。在这一“仿真模型”中，黏弹性边界被用来吸收外传的散射波。因此，计入了无限地基辐射阻尼的影响。利用该“仿真模型”计算了龙江拱坝的地震反应。计算结果表明：考虑无限地基辐射阻尼的影响。龙江拱坝的动拱梁应力与无质量地基模型比较均有较大幅度的降低，最大降幅约在40％～50％范围内。且导致正常蓄水位和死水位条件下。大坝静动综合的最大主拉、主压应力明显降低。

According to the work principle of shaking table for seismic simulation, numerical simulation of shaking table was performed by use of the computer technique. In the simulation model, the vlsco-elnstic boundary was employed to absorb outwardspreading scattering waves; therefore, the influence of infinite foundation radiation damping was taken into account. The calculation of the earthquake response of Longjiang Arch Dam as a case study shows that the infinite foundation radiation damping associated with wave propagation away from the dam decreases the dynamic arch cantilever stress by 40 %-50 % as compared with massless foundation models and results in obvious decrease of maximal principal tensile stress and maximal principal compressive stress of the dam in static and dynamic composite states under normal water storage level and dead water level.