Abstract: To address the issues of poor blast resistance and inadequate sealing performance of existing inflatable fire area closures, a novel method combining multi-inflatable airbags with a truss structure for sealing was designed. This approach considers the advantages and disadvantages of mainstream inflatable closure patents and potential technical challenges. Numerical simulation studies (using Ansys LS-DYNA) and field tests were conducted to evaluate the blast resistance and leak-sealing performance of the joint sealing system. Simulation results showed that under explosion shock waves, the airbags exhibited axial compression displacement along the tunnel direction, with deformation gradually decreasing outward from the cross-sectional center. The maximum displacement of the truss structure under pressure occurred at the weakly supported arc-shaped top section, corresponding to the highest localized stress. In the lower, densely supported sections of the truss, stress concentration was observed at the bolted joints, with a maximum stress value of 625 MPa, below the yield stress of the material. The joint sealing system withstood overpressure shock waves up to 0.17 MPa. Optimization measures were proposed to address stress concentration at the top weak supports and bolted joints, including densifying supports and increasing truss length to reduce stress at joint locations. The joint sealing device is adaptable to tunnel of different shapes ranging from 7 m² to 11 m², with short setup time, ease of operation, and strong adaptability. The ground inflation of the sealed airbag to the working pressure can be completed within 20 minutes, after 24 hours of being stationary, the airbag pressure remained above 110 kPa, demonstrating excellent pressure retention. A sealing and leakage-blocking test was conducted on a simulated tunnel from Kailuan Mine Emergency Rescue Team, and the test results showed that the sealing airbags closely adhered to the surrounding tunnel without significant leakage paths, confirming the good sealing effect of the combined system, which is also reusable.