Forensic analysis of inflatable structure collapse using 3D simulation

The collapse of an inflatable structure is not an instantaneous event, but a cascade of failures that begins in the textile material or the pressure system. In this technical article, we will analyze the root causes of collapse (membrane failure, differential pressure loss, and wind loads) through a step-by-step 3D reconstruction. The goal is to provide modelers with a forensic guide to simulate the deformation and rupture of these temporary systems.

Simulation of the Deformation and Textile Rupture Sequence 🏗️

To model the collapse, the nominal internal pressure (generally between 200 and 500 Pa) and the textile properties (PVC-coated polyester, with a tensile strength of 3 kN/m) must first be established. In the simulation, failure usually begins with a micro-perforation or a tear in the high-frequency welds. As the pressure drops, the membrane stress redistributes, generating wrinkles and folds that amplify the deformation. The side wind (25 m/s load) introduces a flapping effect that accelerates material rupture. The visual sequence shows how the dome loses its stable curvature, collapsing towards the windward side in less than 2 seconds.

Lessons for Safety in Temporary Structures ⚠️

Comparing the simulation results with the EN 13782 standards (Temporary Structures), it is observed that many real-world collapses occur due to undersized ground anchors. The 3D reconstruction reveals that textile failure is secondary; the primary cause is often the inability of the guying system to resist uplift. For modelers, this implies that any forensic simulation must prioritize the interaction between wind, internal pressure, and the stiffness of the tie-downs, not just the fabric's strength.

Is it possible to predict the exact point of the failure cascade in an inflatable structure by analyzing the progression of material deformation through non-linear 3D simulations?

(PS: Simulating a collapse is easy. The hard part is not crashing the program.)