突然开孔结构的风致内压及屋盖响应研究

在系统阐述开孔结构的内压瞬态波动理论及屋面结构风振响应问题的基础上,对开孔瞬间的脉冲内压、气流稳定后屋盖结构所受的最大净风压进行了估算;同时讨论了内压作用下的屋盖响应特性。研究表明,建筑物突然开孔时的内压脉冲对结构安全威胁很大,对于已经存在开孔的结构的屋盖由于受到内外压的共同作用要比开孔前承受更大的风荷载,从而解释了台风或者飓风期间建筑物门窗突然破坏时容易进一步造成屋盖破坏的现象。屋盖响应分析结果表明,当开孔结构的H e lm ho ltz频率、弹性屋盖的固有频率以及来流中所包含的涡脱落频率,三者接近时,屋盖将发生较大的共振。

Wind-induced internal pressure and roof response of sudden opening building

All previous wind disaster investigations have substantiated that higher wind-induced internal pressure in the case of sudden opening due to destruction of windows or doors during hurricane is one of the major cautions for collapse of fastigiums and roofs.Based on internal pressure transient theory,internal pressure and the roof response of a sudden opening building were theoretically studied.The numeric results show that internal pressure impulsion is a threat against building security in strong wind.It is also proved that roof failure can easily occur under combination affects of large internal pressure and external pressure.Studies on roof response of sudden opening indicate that resonance vibration will be caused if Helmholtz frequency,roof natural frequency and eddy wake current frequency are the same.