Experimental Study on the Thermal Performance of Fire-Resistant Plaster for Tunnel Applications

Passive fire protection is a key component of tunnel safety strategies, aiming to delay temperature rise in the concrete lining and limit heat transfer through structural elements. This article presents findings from full-scale fire experiments conducted at the research centre “Zentrum am Berg”. The tests were divided into two groups to evaluate the thermal performance of fire-resistant coating under realistic fire scenarios in tunnel environments. The first group examined plaster layers of maxit ip 160 T with thicknesses of 4 cm, 3 cm, and 2 cm applied directly to tunnel walls and exposed to moderate heat loads representative of passenger vehicle fires, with varying ventilation settings. The second group involved prefabricated panels with 4 cm fireprotection plaster maxit ip 160 T layers subjected to more severe fire exposures using burning magnesium and controlled gas flames. Temperature measurements were recorded on the fire-exposed plaster surface and at various depths beneath using thermocouples. The collected data provide a robust basis for assessing the insulation performance of the tested material. Preliminary results indicate effective thermal protection, supporting the plaster’s potential for use in tunnel fire safety applications.