单向载荷下防火铝塑复合板屈曲特征研究

Buckling characteristics of fireproof aluminum plastic composite plate under unidirectional load

用改进的Riks弧长法研究建筑外墙用防火铝塑复合板屈曲特征,设置单向载荷及边界条件,提取压扭组合、轴向压缩、切向扭曲、先压后扭、先扭后压5种工况下试件的屈曲特征。结果表明:单向加载初期试件变形不明显,屈曲承载变化小,后期局部出现波浪状变形,屈曲部位承载失效,无变形部位承载增加;弹性模量增大时,轴向压缩、先扭后压和切向扭曲载荷下的承载增加,先压后扭和压扭组合载荷下承载下降;压缩载荷为500 MPa时,达到最高极限强度;屈曲前试件纵向应力呈峰状且位移宽度较小,屈曲后纵向应力最高达130 MPa,位移扩大为-150~150 mm,且逐渐靠近试件中部。

The improved risk arc length method was used to study the buckling characteristics of fireproof aluminum plastic composite plate used for building exterior wall. The buckling characteristics of specimens under five kinds of unidirectional loading conditions,i.e. Compression torsion combination,axial compression,tangential torsion,compression before torsion and torsion before compression,were extracted by setting unidirectional loading and boundary conditions. The results show that the deformation is not obvious at the initial stage of unidirectional bias loading,and the changes buckling bearing capacity are small.At the later stage,the specimen has local wavy deformation,the bearing capacity at the buckling position is ineffective,and the bearing capacity at the nondeformed part increases. When the elastic modulus increases,the load under three kinds of unidirectional bias loading,axial compression,torsional compression and tangential torsion increase,and the loads of compression before torsion and axial-torsional loads decrease. When the compressive load is 500 MPa,the specimen reaches the maximum ultimate strength. The longitudinal stress of the specimen shows peak shape before buckling and the displacement width is relatively small. After buckling,the maximum longitudinal stress reaches 130 MPa,and the displacement expands to-150-150 mm,gradually approaching the specimen middle position.