人防工程活门槛防护密闭门门框荷载分布研究

Study on Load Distribution of Doorframe for Airtight Blast Door with Movable Threshold in Civil Air Defense Works

活门槛防护密闭门在人防工程中应用广泛,因活门槛刚度低,其门扇受力与普通固定门槛防护密闭门差别大。现行相关设计规范未见针对活门槛防护密闭门门框墙设计的荷载分配算法,一般参照普通防护密闭门进行设计。针对活门槛防护密闭门门框受力问题,构建了活门槛混凝土防护密闭门有限元数值模型,采用ANSYS/LS-DYNA对平板活门槛钢筋混凝土防护密闭门在冲击波超压作用下的动态响应进行了模拟计算,分析了门扇对门框作用力的变化过程及荷载分布规律。结果表明:活门槛的刚性较弱,其承载作用可以略去不计,门扇对门框的作用力随门扇的振动而变化,门框荷载分布与门扇的变形状态密切相关,门扇达到准静态时的门框荷载分布主要取决于门孔的宽高比。

The airtight blast door with movable threshold is widely used in civil air defense engineering.Due to the low stiffness,the load of the door leaf is quite different between the door with movable threshold and that of ordinary fixed threshold.The current design standardizes have no load distribution computational methods for the airtight blast door with movable threshold,generally designed referring to the ordinary airtight blast door.In order to study the reaction force of the doorframe of the flat concrete airtight blast door,the finite element numerical model of flat concrete airtight blast door with movable threshold is constructed.The dynamic behavior of the flat concrete airtight blast door with movable threshold under nuclear explosion pressure is simulated with ANSYS/LS-DYNA.The variety procedure of the force between leaf and doorframe and the load distribution of the doorframe are presented.The calculation results indicate that the support capability of the movable threshold can be omitted for its weak rigidity.The force between leaf and doorframe fluctuates with the vibration of the leaf.The load distribution of the doorframe is closely related to the deform state of the leaf.The load distribution of the doorframe is mainly decided by the ratio of highness and wideness of the doorframe when the leaf reach quasi-static state.