穿孔与热辐射耦合作用下固定拱顶钢储罐的失效机理

To study the failure mechanism of a large fixed-roof Q345 steel tank under coupling effects of the fragment impact and pool-fire heat radiation, finite element models of thermal and dynamic response analysis under coupling effects of the high-velocity fragment perforation and heat radiation of a burning tank was established by Abaqus. The dynamic behaviors of a fixed-roof tank subjected to high-velocity fragment perforation were investigated. And the effect of the heat radiation on the thermal buckling behaviors of a perforated tank was analyzed. Moreover, the stress distribution and variation on the cylindrical shell was studied. The results indicated that the thermal buckling of the tank begun from the connection of the cylindrical shell and dome under the single effect of the heat radiation. And the cylindrical shell wrinkled along the circumferential direction with the temperature increasing at the post-buckling state. The reason was that circumferential and meridional stresses alternated between tension and compression to maintain the balance. The tank was perforated, and the thermal buckling of the perforated tank started from both sides of the perforation under coupling effects of the perforation and heat radiation. Moreover, perforation led to stress concentration in the plastic deformation zone and its vicinity. Compared with the unimpacted storage tank, the wall of the perforated storage tank was at a higher stress level and was more prone to instability. Therefore, the fire resistance of the perforated storage tank reduced, and the thermal buckling mode also changed.