Failure mechanisms of prefabricated multi-family buildings under gas explosions

Abstract

Large-panel buildings are multi-story structures made of prefabricated large-sized wall and floor panels, where the integrity of connections between elements plays crucial role in structural integrity. Under gas explosions, these structures exhibit specific failure mechanisms that differ from those of monolithic slab-column systems. The potential for preventing progressive collapse in large-panel buildings depends on the arrangement of load-bearing walls, the effectiveness of alternative load paths, and the resistance of structural ties. Despite adherence to modern safety standards, unexpected structural failures still occur, highlighting the need for a deeper understanding of these mechanisms.

This study examines real cases of gas explosions in large-panel buildings, identifying three primary failure mechanisms. Type 1 – local damage limited to a one room (usually the kitchen), with limited structural impact on adjacent elements. Type 2 – damage to the entire apartment, potentially leading to progressive collapse depending on tie resistance. Type 3 – High-energy explosions in basements or extensive areas of gas saturation, often causing progressive collapse and significant structural damage. Analysis reveals that spatially appropriately shaped cross-wall construction systems significantly improve structural resilience by enhancing alternative load paths and reducing progressive collapse probability. Additionally, structural damage severity correlates with energy and extent of the explosion, which is consistent with modern technical standards.

The findings contribute to a more comprehensive understanding of how large-panel buildings behave under gas explosion overpressure, emphasizing the importance of proper reinforcement detailing, high-quality workmanship, and periodic inspections to detect corrosion or weakened connections. The study provides practical recommendations for improving design strategies, maintenance practices, and safety measures to prevent or mitigate progressive collapse. These insights are critical for enhancing the long-term safety and resilience of large-panel residential buildings, ensuring their continued usability under both normal and extreme conditions.