Experimental and Numerical Analysis of Glass Fragmentation Kinetics in Typical Residential Gas Explosions

High-velocity fragments from building glass pose severe safety hazards during gas explosions. This study investigated the failure mechanisms and fragmentation dynamics of architectural glass under liquefied petroleum gas (LPG) and natural gas (NG) explosions using integrated full-scale experiments and numerical simulations. The results demonstrate that gas type is the dominant factor influencing blast load and glass response. Owing to its higher energy density and burning velocity, LPG produced a far-field overpressure peak of 78.2 kPa, approximately 8 times greater than that of NG, which was 10.4 kPa. Additionally, LPG generated a faster blast wave (arrival time: 0.62 versus 1.75 s, respectively) and 78% higher initial fragment velocities (15.1 m/s compared to 8.3 m/s, respectively). Gas stratification further affected fracture patterns, with floor-deposited LPG causing top-initiated fracture and ceiling-accumulated NG leading to bottom-initiated failure. Fragment dispersal follows a two-stage acceleration process: initial blast-induced fracture within 1 m, followed by gas-venting-driven acceleration propelling fragments beyond 30 m/s. Mass recovery analysis indicated that only 16.5% of glass was recovered after LPG explosions, compared with 25.54% for NG explosions, indicating significantly farther fragment projection and an expanded hazard zone. Numerical simulations using LS-DYNA with the Johnson–Holmquist ceramic (JH-2) constitutive model accurately captured fracture and fragmentation processes, confirming that thinner glass produces sharper, high-aspect-ratio fragments with elevated penetration risk despite lower velocities. These findings provide valuable insights for safety assessments and structural design in explosion-prone environments.