【摘要】 针对近断层脉冲型地震动的研究大多集中于单脉冲型地震动，对具有多脉冲特征的地震动研究较少.为识别地震数据库中的多脉冲型地震动，采用了一种将卷积与脉冲评估指标相结合的广义连续小波变换(GCWT)方法识别并提取地震动中的脉冲部分.利用该方法从PEER NGAWest2数据库中识别了Chi-Chi地震的非脉冲型、单脉冲型和多脉冲型地震动各7条.比较了3种地震动的速度谱和加速度谱，多脉冲型地震动的谱速度显著大于非脉冲型、单脉冲型地震动的谱速度，且在长周期范围内包含多个峰值.采用离散元软件研究顺层岩质边坡在非脉冲型、单脉冲型和多脉冲型地震动下的动力响应.研究结果表明：(1)多脉冲型地震动引发的边坡潜在滑移带更深，滑坡体体积更大；(2)非脉冲和单脉冲型地震动作用下，边坡对地震动的放大效应随高程呈非线性增加，且单脉冲型地震动在坡顶的放大效应更加明显.多脉冲型地震动的放大效应在边坡1/2高程以下明显大于其他2种地震动，在1/2高程以上与非脉冲型地震动接近；(3)坡体在多脉冲型地震动作用下的最大水平位移约为非脉冲和单脉冲型地震动作用下的2倍，表明多脉冲型地震动对坡体结构易造成严重破坏.更多还原

【Abstract】 Previous studies on near-fault pulse-like ground motions have mainly focused on single-pulse motions, with limited research on multi-pulse motions.To extract multi-pulse ground motions, a method combining generalized continuous wavelet transform(GCWT) and parameter evaluation is employed.Seven non-pulse, single-pulse, and multi-pulse ground motions from the Chi-Chi earthquake in Taiwan were identified from the PEER NGAWest2 database.A comparison of response spectra reveals that multi-pulse ground motions exhibit significantly larger spectral velocities than non-pulse motions, with multiple peaks in the long-period range.Using a discrete element program, the dynamic response of bedding rock slopes under different types of ground motions is analyzed.The results show that:(1)Multi-pulse ground motions generate a deeper potential slip zone and a larger landslide volume.(2)Seismic amplification increases nonlinearly with elevation under non-pulse and single-pulse motions, with stronger amplification at the slope crest for single-pulse motions. In contrast, multi-pulse motions show stronger amplification below mid-slope, with similar amplification above mid-slope as non-pulse motions.(3)The maximum horizontal displacement under multi-pulse motions is approximately three times larger than that under non-pulse and single-pulse motions, indicating a significantly higher risk to slope stability.These findings underscore the critical impact of multi-pulse ground motions on slope stability and structural damage.更多还原