西藏定日6.8级地震震灾分析及启示  

Seismic Disaster Analysis and Lessons Learned from Dingri M6.8 Earthquake in Xizang

作　　者：马星宇 陈相兆[1,2] 张桂欣 闫佳琦[1,2] 王楠 Ma Xingyu;Chen Xiangzhao;Zhang Guixin;Yan Jiaqi;Wang Nan(Institute of Engineering Mechanics,China Earthquake Administration,Harbin 150080,China;Key Laboratory of Earthquake Engineering and Engineering Vibration of China Earthquake Administration,Harbin 150080,China)

机构地区：[1]中国地震局工程力学研究所,哈尔滨150080 [2]中国地震局地震工程与工程振动重点实验室,哈尔滨150080

出　　处：《震灾防御技术》2025年第1期13-23,共11页Technology for Earthquake Disaster Prevention

基　　金：国家重点研发计划项目(2022YFC3005701)。

摘　　要：2025年1月7日9时,西藏定日县发生6.8级地震。截至1月9日6时,此次地震造成了126人遇难,影响场内死亡率高达0.3%。基于台站数据、现场建筑物建(构)造特征等信息,从危险性、承灾体等多角度进行分析,提出此次地震灾害较为严重的可能原因:(1)当地传统民居多为土/石木结构,整体结构性能和延性较差,在地震作用下易产生严重破坏。更为重要的是,这些建筑往往采用的是外围护墙和内部木框架承担土/石木楼板的结构形式,在地震中大量内部木框架歪闪、与墙体分离,没有拉结的屋面和木屋架向房屋内部塌落,造成严重人员伤亡。(2)地震动强度大,有台站记录的水平向峰值加速度最高达到784 cm/s^(2)。且近场地震动短周期成分丰富,竖向地震动作用明显,对震区大量分布的本就较为松散的低层建筑破坏力较大。(3)震区位于西部高海拔地区,地震发生时刚刚日出,天气寒冷,大部分受灾群众尚未外出,人员在室率高。由于高海拔地区的环境和气候恶劣,救援难度较大,导致人员生存率低。根据震害原因,建议在少数民族地区坚持“保持原有传统建筑风格、就地取材、引导建设抗震结构”和“尊重民族习俗、低扰动、价格低廉”的原则,全面推进既有建筑抗震能力提升和新建建筑抗震设防。At 9:00 AM on January 7,2025,a 6.8 magnitude earthquake struck Dingri County,Xizang.As of January 9,the earthquake had resulted in 126 fatalities,with a mortality rate of up to 0.3%within a 100-kilometer radius of the epicenter.Using data from seismic stations and an analysis of local building characteristics,a multi-faceted investigation was conducted from both hazard and vulnerability perspectives.The following key factors contributing to the severity of the disaster were identified:(1)The majority of traditional residential buildings in the region,primarily constructed from earth,stone,and wood,exhibit poor structural integrity and ductility,making them highly susceptible to seismic damage.Additionally,the walls are prone to collapse,losing their vertical load-bearing capacity and leaving minimal survival space after failure.(2)The earthquake produced intense ground motion,with peak acceleration recorded at some seismic stations reaching 784 cm/s^(2)-significantly exceeding local seismic fortification standards.Moreover,the near-field motion contained abundant short-period components,which exerted a particularly destructive force on the low-rise buildings prevalent in the affected area.(3)The earthquake occurred early in the morning in a high-altitude region with a harsh climate,complicating rescue efforts and reducing survival rates.Based on these findings,it is recommended that seismic mitigation efforts in minority regions adhere to the principles of preserving traditional architectural styles,utilizing local materials,and promoting the construction of earthquake-resistant structures.Additionally,efforts should focus on minimizing disruptions to local communities while maintaining cost-effectiveness.A comprehensive strategy should be implemented to assess and reinforce existing buildings and enhance the seismic resilience of new constructions.

关 键 词：定日地震 震灾分析 致灾原因 抗震能力提升 

分 类 号：P315.9[天文地球—地震学]