水平向加速度峰值比为两条水平向加速度峰值的较大值与较小值的比值;竖向与水平向加速度峰值比为竖向加速度峰值与两条水平向加速度峰值的较小值的比值。以2 129次破坏性地震的156 783组地震动加速度记录为基础,研究水平向、竖向与水平向加速度峰值比值的统计分布特征,对加速度记录按照震中距、震级和震源深度进行分类统计分析。统计分析结果表明:水平向加速度峰值比总体平均值为0.83,水平向加速度峰值比≤0.85的累积概率为63%;竖向与水平向加速度峰值比总体呈现极值Ⅱ型分布特征,竖向与水平向加速度峰值比总体平均值为0.44,竖向与水平向加速度峰值比≤0.65的累积概率为92%。水平向加速度峰值比随震中距的增大而增大,竖向与水平向加速度峰值比随震中距的增大而减小。竖向与水平向加速度峰值比随着震级的增大而增大;在大震(7＜M≤8)近场(0＜R≤60 km)增大的趋势更加明显,水平向加速度峰值比与震级的相关关系不明显。在震中距0~100 km范围内,水平向、竖向与水平向加速度峰值比随着震源深度的增加而增加。
In this work, the statistical distribution characteristics of peak acceleration ratios in the horizontal, vertical, and horizontal directions were studied on the basis of 156 783 groups of ground motion records from 2 129 destructive earthquakes, and the acceleration records were classified and analyzed in accordance with epicentral distance, magnitude, and focal depth. Results showed that the overall average value of the acceleration ratio peak in the horizontal direction was 0.83, and the cumulative probability of the acceleration peak ratio in the horizontal direction≤0.85 was 63%. The ratio of vertical to horizontal peak accelerations generally presented an extreme type II distribution with an average value of 0.44, and the cumulative probability of the ratio of vertical to horizontal peak accelerations ≤0.65 was 92%. With the increase in epicentral distance, the horizontal peak acceleration ratio increased, whereas the ratio of vertical to horizontal peak accelerations decreased. The ratio of vertical to horizontal peak accelerations increased with the increase in magnitude, and this increasing trend was more obvious under large (7＜M≤8) near field (0＜R≤60) earthquakes. Meanwhile, the correlation between the horizontal peak acceleration ratio and magnitude was not obvious. Within 0-100 km from the epicenter, the peak acceleration ratios in the horizontal, vertical, and horizontal directions increased with the increase in focal depth.
孔宇阳,柳煜,廉超,陈新强.强地面运动加速度峰值三向比值统计分析[J].地震工程学报,2023,(1):43-49,57. KONG Yuyang, LIU Yu, LIAN Chao, CHEN Xinqiang. Statistical analysis of peak acceleration ratios in three directions for strong ground motions[J]. China Earthquake Engineering Journal,2023,(1):43-49,57.复制