汶川地震中教学楼倒塌调查分析——5·12汶川地震三周年祭

Investigation of collapse of teaching buildings during the Wenchuan Earthquake: third anniversary memorial of 5·12 Wenchuan Earthquake

根据对汶川地震中村镇地区教学楼破坏情况的实地调查,详细介绍了倒塌现象并进行了深入分析。研究结果表明:结构方案缺陷、整体稳固性不足是造成倒塌的根本原因;构件间连接构造措施缺失导致结构解体;而结构材料的脆性和施工质量失控,造成结构综合抗力不足。具体表现为:结构体系头重脚轻,刚度不均;传力途径单薄,缺乏冗余约束;关键传力部位严重削弱,缺乏抵抗水平作用的能力;墙体缺乏圈梁-构造柱约束;预制板没有任何连接构造措施;材料(混凝土、砌体、冷加工钢筋)强度不足或延性很差;任意加层改造等。历史造成的管理缺失和不遵守有关的标准、规范是人为方面的原因。因此,加强管理和遵守标准规范至关重要。

Based on the on-the-spot investigation of the damages to teaching buildings of schools in rural areas during the Wenchuan Earthquake,the collapse phenomena was introduced and analyzed in depth.Research results indicate that the deficiency of the conceptual design of the structure,i.e.the insufficient whole structural robustness,is the fundamental cause.The dismantle of the structure is attributed to the deficient connection construction measures.The brittleness of the construction material and the uncontrollable construction quality leads to the inadequate overall resistance of structure.The collapses of structures were also due to the following reasons： the top-heavy structural system,uneven distribution of stiffness,inadequate load transfer path,lack of redundant constraint.Critical components of load path severely weakened,lack of horizontal load resistance,lack of ring beam-structural column restraint,precast slab without any connection measures,insufficient strength and ductility of materials such as concrete,masonry,and cold steel.Arbitrarily added stories,and etc.As a result of historic reasons,the poor management and violation of standards are human related factors.Consequently,it is important to strengthen management and the compliance with standards and codes.