Blast resistance of reinforced concrete single room under internal explosive load

In order to study the anti-explosion performance of a single-room reinforced concrete building under internal explosion loads, a full-scale reinforced concrete single-room building, whose dimensions were 4m×4m×3m, was designed and constructed. For the internal explosion test, 3kg TNT was placed in the geometric center of the room. Sensors were installed at the center of the shear wall and roof to record data and analyze the damage characteristics of the single-room structure. In addition, an anti-explosion numerical model of the reinforced concrete single-room structure was established and verified using the LS-DYNA software. The weight of the explosives in the numerical model was changed to study the damage process and shock wave propagation law of the single-room building. Based on the experimental and simulation results, the damage modes of the single room structure were categorized by the dimensionless weighted parameter Dr, and relevant empirical formulas were obtained through data fitting. The results show that when 3kg TNT explodes in the geometric center of the room structure, the single-room structure exhibits roof bulging, with long cracks appearing along the roof edges. However, the whole structure does not collapse; Under the internal explosion condition, the local damage characteristics of reinforced concrete buildings are not only closely related to the explosive yield, but also significantly affected by the design of structural connection nodes and structural details; Due to the delayed dynamic response of reinforced concrete, the next shock wave has acted on the building before the last shock wave has reacted obviously, which subjects it to multiple impacts within a very short time; By varying the charge weight, five damage-aggravating modes (Model I to Model V) were identified. The five damage modes were quantitatively defined using the weighted parameter Dr, and a function curve relating it to the explosive equivalent was fitted. These research findings can provide a reference for damage assessment of shear wall-structured rooms.