2025年缅甸7.9级地震灾害特点浅析

Damage characteristics and brief analysis of the 2025 Myanmar M_S7.9 earthquake

摘要

2025年3月28日,缅甸中部实皆省发生7.9级地震,此次地震造成了重大经济损失和人员伤亡。基于震后灾区震害调查,总结建筑结构的震害特点,初步分析震害原因。沿断层扩展的地表裂缝延伸上百千米,对建筑及工程结构破坏严重,同时造成场地液化、边坡失稳等地质灾害,进一步加剧了灾情。灾区量大面广的主要建筑结构形式是木结构,轻质围护墙的木结构房屋的抗震性能很好,即使震损也只有很低的伤亡率。少数不设防砖混结构房屋,年代久远、抗震性能差,震害重。钢筋混凝土框架结构总体抗震性能较好,但存在抗震不利因素时也会降低抗震能力,造成重大人员伤亡。最后浅析了灾情特点。震害经验的总结对提高抗震能力有重要的现实意义。

Abstract

On March 28, 2025, a magnitude M_S7.9 earthquake occurred in Sagaing Region, central Myanmar. The earthquake caused significant economic losses and casualties. Based on the field survey, the characteristics of structure damage are summarized, and the causes of earthquake damage are analyzed preliminarily. The surface cracks extending hundreds of kilometers along the fault zone seriously damaged buildings and engineering structures, and caused geological disasters such as liquefaction and slope instability, which further exacerbated the losses. The main structural type in the disaster area is wooden structure. The wooden houses with light enclosure walls have good seismic performance, and even if they are damaged by earthquake, the casualty rate is very low. Few unreinforced masonry structure houses with old age and poor seismic performance, were severely damaged in this earthquake. Reinforced concrete frame structure buildings are mainly distributed in cities, which seismic performance is relatively better. But a few RC buildings had unfavorable seismic factors, which reduced the seismic capacity and caused serious casualties. Finally, the disaster characteristics are briefly analyzed. The summary of earthquake disaster experience has important practical significance, which is beneficial for improving seismic resistance.

关键词

缅甸7.9级地震 / 震害调查 / 震害特点 / 灾情分析

Key words

Myanmar M_S7.9 earthquake / field survey / damage characteristics / disaster analysis

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基金资助

中国地震局工程力学研究所基本科研业务费专项资助项目(2019B11)