Влияние заглубления легкосбрасываемых конструкций на формирование взрывной нагрузки

Introduction. Using relief structures to reduce pressure in case of an indoor explosion is widely spread. Moreover, it is legitimized by regulations. However, regulatory documents ignore the well-known fact that the embedment depth of relief structures is equal to or exceeds the value of their thickness. As of the moment when the relief structure begins to move after the disintegration of its bonding from the frame and up to the moment when it leaves the opening, explosion pressure may rise exponentially. Goal. The goal is to determine the effect of embedment depth of a relief structure on the pressure rise during an indoor explosion at the initial stage of explosion development when the relief structure moves in the opening. Research methods. The experiment was conducted in a blasting chamber with an opening door where the model of a relief structure was installed. Results and discussion. The authors found that, if the chamber remained hermetically sealed, the explosion pressure increased proportionally to t 3 , at least, up to Δ P < 10 kPa. In case of free motion of a relief structure in the opening, the tightness of the system degraded as the explosion developed. As a result, the relief structure left the opening if the pressure value was below that identified as a result of calculations made for conditions of tightness. Nevertheless, an increase in pressure, even in case of poor tightness, followed a change in dimensionless parameter B , which determined the process at this stage of explosion development. Conclusions. The process is controlled by dimensionless parameter B . The quantitative difference is triggered by the system tightness loss, accompanying the pressure rise, and emergence of the friction force accompanying the attempt to hermetically seal the system. These two circumstances reduce the relative explosion pressure rise, while the relief structure is in motion in the opening if the friction force is taken account of in the course of identifying the value of pressure at which bonding between the relief structure and the building are disrupted.