建筑坍塌事故有哪些特点？
What are the characteristics of building collapse accidents?
1、突发性、不可预见性强，人员逃生难：建筑坍塌受建筑结构、建筑质量、自然条件等因素影响。建(构)筑物倒塌事故随时可能发生，且事故前兆很不明显，允许人员逃生的时间极短，待人们察觉时，倒塌事故往往已经造成了严重后果。
1. Sudden, unpredictable, difficult to escape: building collapse is affected by building structure, building quality, natural conditions and other factors. Building (structure) collapse accidents may occur at any time, and the precursor of the accident is not obvious, and the time for people to escape is very short. When people are aware, the collapse accidents often have caused serious consequences.
2、易引发次生灾害：突发性建筑物坍塌事故，可能造成建筑物内部燃气、供电等设施毁坏，导致火灾的发生。
2. It is easy to cause secondary disasters: sudden building collapse accident may cause the destruction of gas, power supply and other facilities inside the building, leading to the occurrence of fire.
3、社会影响大。
3. It has great social influence.
4、救援难度大：由于被埋压待救的被困人员较多，受装备限制，救援行动的有效性势必减弱，灾后救助往往是长时间连续作战。
4. Rescue is difficult: due to the large number of trapped people buried and waiting for rescue, the effectiveness of rescue operations is bound to weaken due to the limitation of equipment, and the post disaster rescue is often a long-term continuous operation.