燃气爆炸荷载作用下综合管廊破坏历程研究

采用ANSYS/LS-DYNA软件,结合MAT_72R3和HJC两种混凝土本构模型,建立地下综合管廊(有3个舱,电力舱靠左侧,综合舱居中,燃气舱靠右侧)三维模型,对燃气爆炸荷载作用下管廊损伤破坏历程和周围土体动力响应进行了数值模拟。研究结果表明:地下综合管廊结构的损伤破坏历程是由燃气舱局部损伤破坏逐渐扩展至综合舱和电力舱,燃气舱主要向四周扩张;管廊各测点在爆炸荷载作用下产生的最大水平位移均大于最大竖向位移;在爆炸荷载作用下,管廊燃气舱顶板的振动现象明显且速度呈现周期性衰减变化;由于燃气舱直接承受爆炸荷载作用,最大速度发生在燃气舱右侧壁测点。建议工程实践中在燃气舱和其他舱室之间设置一定的缝隙,以阻碍爆炸应力波向其他舱室扩展,从而避免其他舱室进一步发生破坏。在实际设计管廊时,应增强管廊的抗滑移能力。

Study on Destruction Process of Utility Tunnel under Gas Explosion Load

By using ANSYS/LS-DYNA soff-ware,combined with two kinds of concrete constitutive models of MAT_72R3 and HJC,a three-dimensional model of underground utility tunnel(with three depart-ments,electric department on the left,comprehensive department in the middle and gas department on the right)is established to mumerically simulate the destruction process of utility tunnel and the dynamic response of surrounding soil under gas explosion load.The results show that the damage destruction process of the underground utility tunnel structure gradually extends from the local damage destruction of the gas department to the comprehensive department and the e-letric department,and the gas department mainly expands to the surroundings;The maximum horizontal displacement of each measuring point in the utility tunnel under the explosion load is larger than the maximum vertical displacement;Under the explosion load,the vibration phenomenon of the roof of the gas department in the utility tunnel is obvious and the velocity exhibits periodic decay changes;Because the gas department is directly subjected to the explosion load,the maximum velocity occurs at the measuring point on the right wall of the gas department.It is suggested that in engineering practice,a certain gap should be set between the gas department and other departments to prevent the explosion stress wave from expanding to other departments,so as to avoid further damage to other departments.In the actual design of the utility tunnel,the anti-slip ability of the utility tunnel should be enhanced.