Although intensive research of the influence of ground motion duration on structural cumulative damage has been carried out, the influence of dynamic responses in underground tunnels remains a heated debate. This study attempts to highlight the importance of the ground motion duration effect on hydraulic tunnels subjected to deep-focus earthquakes. In the study, a set of 18 recorded accelerograms with a wide-range of durations were employed. A spectrally equivalent method serves to distinguish the effect of duration from other ground motion features, and then the seismic input model was simulated using SV-wave excitation based on a viscous-spring boundary, which was verified by the time-domain waves analysis method. The nonlinear analysis results demonstrate that the risk of collapse of the hydraulic tunnel is higher under long-duration ground motion than that of short-duration ground motion of the same seismic intensity. In a low intensity earthquake, the ground motion duration has little effect on the damage energy consumption of a hydraulic tunnel lining, but in a high intensity earthquake, dissipation of the damage energy and damage index of concrete shows a nonlinear growth trend accompanied by the increase of ground motion duration, which has a great influence on the deformation and stress of hydraulic tunnels, and correlation analysis shows that the correlation coefficient is greater than 0.8. Therefore, the duration of ground motion should be taken into consideration except for its intensity and frequency content in the design of hydraulic tunnel, and evaluation of seismic risk.

尽管已经对地震动持续时间对结构累积损伤的影响进行了深入研究，但是地下隧道中动力响应的影响仍然是一个激烈的争论。这项研究试图强调地震动持续时间效应对遭受深层地震的水力隧道的重要性。在这项研究中，采用了一组18个记录的加速度图，其持续时间范围很广。频谱等效方法可以将持续时间的影响与其他地面运动特征区分开，然后使用基于粘性弹簧边界的SV波激励模拟地震输入模型，并通过时域波分析方法进行了验证。非线性分析结果表明，在相同地震烈度下，长距离地震动作用下水工隧洞的坍塌风险要高于短时间地震动作用。在低烈度地震中，地震动持续时间对水工隧洞衬砌的破坏能量消耗几乎没有影响，但是在高烈度地震中，混凝土的破坏能和破坏指数的消散显示出非线性的增长趋势，并伴随着增加。地震动持续时间的变化，对水工隧洞的变形和应力影响很大，相关分析表明，相关系数大于0.8。因此，在水力隧道的设计中，除了地震动的强度和频率含量外，还应考虑地震动的持续时间，