The Damage Index Characteristics Research of Ms6.5 in Hualian County, Taiwan in 2018

李宗超,陈学良,吴清,李铁飞,李昌珑 中国地震局地球物理研究所 北京 100081, 中国 lizongchaoigo@163.com Abstract: On February 4, 2018, a Ms6.5 occurred in Hualien County in Taiwan Province. The source depth was 10 km. This earthquake killed 17 people and injured 285 people. The earthquake also caused huge property losses. Most of the casualties of the earthquake were caused by the collapse and damage of the buildings. The near field strong ground motion was the direct reason which caused the collapse of the building. The collapse of the buildings was greatly related to the amplitude and frequency of circulation of ground motion. The seismic response of system accumulated damage under cyclic load depends not only on the maximum amplitude of motion but also on the duration of motion. Many researchers suggest that the effective number of ground motion cycles is more reflective of seismic damage than the duration. The destructive ability of seismic ground motion depends on the amplitude of the movement and the number of cycles. In the geotechnical earthquake engineering, the number of motion cycles is the most important. Many researchers believe that the number of motion cycles is also an important factor in structural seismic design and damage assessment. Because the strength, stiffness and energy dissipation of the structure decreases with the increase of the load cycle, the amplitude itself is not sufficient to evaluate the seismic performance of the structure. In this paper, the spatial distribution characteristics of the damage index of Hualian earthquake is analyzed, and the correlation between the damage index and seismic intensity is analyzed. Keywords—damage Index, Hualian eartrhquake, characteristics analysis, seismic intensity 摘要:2018 年 2 月 4 日,台湾省花莲县附近海域(北 纬 24.2 度,东经 121.72 度)发生 6.5 级地震,震 源深度 10 千米,地震造成 17 人遇难,285 人受伤, 地震也造成了巨大的财产损失。本次地震的绝大部 分伤亡是由于建筑物倒塌破损造成的,而近场强地 震动是造成建筑物倒塌的直接原因,建筑物倒塌与 地震动的振幅和循环次数相关性极大。系统在循环 荷载下累积损伤的地震响应不仅取决于运动的最 大振幅,还取决于运动的持续时间。许多研究人员 提出,有效的地面运动周期数比持续时间更能反映 地震破坏能力。地震地面运动的破坏能力取决于运 动的振幅和循环次数。在岩土地震工程中,运动循 环次数是最重要的。许多研究人员认为,运动循环 次数也是结构抗震设计和损伤评估方面的一个重 要因素。由于结构的强度、刚度和耗能能力随着荷 载循环次数的增加而降低,因此振幅本身不足以评 估结构的抗震性能。本文将着重分析研究了花莲地 震的损伤指数的空间分布特征,并结合实际的灾害 烈度分布特征,分析了震害指数与地震烈度的相关 性。 关键词:损伤指数,花莲地震,特征分析,地震强 度