A field blast test including 6 specimens was conducted to investigate the effect of the axial compression ratio,the scaled distance,the hollow ratio and the shape of the facing blasting side on the dynamic response of ultra-high performance steel fiber reinforced concrete-filled double skin steel tube columns (UHPSFRCFDST).Then a three dimensional finite element model (3D FEM) was built using the LS-DYNA software to analyse the dynamic response and damage mechanism of UHPS FRCFDST columns under blast loading,and it was validated by comparison of simulation with blast testing results.Based on this model,the effect of such key parameters as the axial compression ratio,the hollow ratio,the steel ration,the thickness and strength of the inner or outer steel tube,on the blast-resisting performance of UHPSFRCFDST columns was presented.The results indicate that the 3D FEM can accurately describe the dynamic response of UHPSFRCFDST columns under blast loading.The blast-resisting performance of UHPSFRCFDST columns can be improved by increasing the axial compression ratio in a certain range,whereas the damage of the specimens will aggravate when this ratio goes above a critical value.Moreover,the blast-resisting performance of UHPSFRCFDST columns can be enhanced by reducing the hollow ratio or the diameter to thickness ratio of the inner and outer steel tube,and the effect can also be achieved by increasing the steel proportion or the strength of the outer steel tube.However,the strength of the inner steel tube has little effect on the blast-resisting performance of UHPSFRCFDST columns.%通过6根圆形中空夹层钢管超高性能钢纤维混凝土(UHPSFRCFDST)柱爆炸破坏实验,研究了轴压、折合距离、空心率和迎爆面形状对其动态响应及损伤破坏的影响,并运用LS-DYNA软件建立了爆炸荷载作用下UHPSFRCFDST柱动态响应的有限元模型.在验证了模型有效性的基础上,运用参数化分析方法,研究了轴压比、空心率、含钢率、内层和外层钢管径厚比及其强度等关键参数对圆形UHPSFRCFDST柱抗爆性能的影响.结果表明:有限元模型能够有效地分析UHPSFRCFDST柱在爆炸荷载作用下的动态响应及损伤破坏;在小于临界轴压时,提高轴压比能够提升UHPSFRCFDST柱抗爆性能,但超过临界轴压后继续提高反而会加重其损伤破坏;减小空心率或内、外层钢管径厚比均可有效提升UHPSFRCFDST柱的抗爆性能,提高含钢率或外层钢管强度也能达到相同效果,但提高内层钢管强度对其抗爆性能的提升作用并不显著.
展开▼
