爆炸容器塑性失稳和变形吸能

Plastic Instabilities and Deformation Energy Absorption of Explosion Containment Vessels

爆炸容器设计通常采用等效静载法,结构的动态响应严格限制在弹性范围,有必要研究基于塑性变形的设计方法。由本构方程出发,从理论上分析了韧性材料在塑性状态下发生失稳的条件,即临界失稳应变等于材料拉伸试件发生颈缩时的应变;探讨了爆炸容器塑性拉伸失稳的机理,认为爆炸容器塑性拉伸失稳是"位移控制",不同于一般静态压力容器的"载荷控制",属于几何失稳。对圆柱钢壳爆炸容器实验数据进行了分析,结果表明采用塑性变形设计可以充分利用材料的塑性吸能效应,大幅度降低容器重量。

The method of equivalent static loading is commonly used in the engineering design of explosion containment vessels(ECVs),which considers the dynamic response of the structures is limited in the elastic range.It is necessary to investigate the design method based on plastic deformation.From the constitutive equation,the tensile instabillty criterion of ductile material at plastic stage was deduced theoretically,viz.the critical instability strain is equal to the strain at necking of the sample in tensile test.The mechanism of plastic tensile instability on ECVs was discussed,and it is believed that the mechanism of tensile instability on ECVs is 'displacement control' other than 'load control' which occurs in common pressure vessrls and is attributed to geometric instability.The experimented data of steel cylinder subjected to internal blast was analyzed.It is concluded that the absorbed-energy of the plastic deformation can be sufficiently used and substantial weight reduction of ECVs can be achieved by using the method based on plastic deformation.