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Evaluation of a specific facade system's fire performance can be undertaken using large-scale testing, following the local regulations. The fire test protocol detailed in BS 8414 series is representative of an external fire source, or a fully developed (post-flashover) fire in a room, venting through an opening such as a window that exposes the façade to the effects of external flames. This test can be performed indoors or outdoors, with a wind or air velocity of less than 2 m/s. However, wind can have significant effects on the external flame shape, and thus on the thermal exposure of the tested façade. According to the testing conditions given in BS 8414 series, the test uses a wood crib as a fire source with Heat Release Rate between 2.5 MW and 3.5 MW (3.0 ± 0.5 MW). In this paper, a numerical model of the BS 8414 facility is validated based on experiments for an incombustible façade system. Then, the influence of the wood crib contribution on the heat exposure is investigated numerically, using three different values of the wood crib HRR. It was thus shown that the uncertainty allowed for wood crib HRR in BS 8414 with a peak rate of (3.0 ± 0.5) MW and up to 4 MW had no significant influence on the temperature results achieved for the calibration system, but had an impact on the heat flux imparted to the walls for the lower HRR value. The effect of an external wind with three different directions is addressed in terms of variation of the thermal exposure on the façade. A strong impact was observed in terms of patterns of fire exposure and flame height. [ABSTRACT FROM AUTHOR]

Observations and numerical studies have allowed an understanding the fire development inside apartments and over the façade during the Grenfell Tower fire. During these analyses, the highlighted need was for a deeper investigation into the failure of windows during the fire. This detailed and complex model for window failure validates the thermal breakage criteria used in fire simulations of the whole Grenfell Tower fire. However, the present investigation is dedicated to a single pathway for the influx of fire and toxic smoke. Other pathways from the façade to the apartments, such as the melting of elements surrounding the window frame, are not addressed here. To analyse window behaviour during fire, Finite Element Method thermomechanical modelling is used. First, a heat transfer analysis is performed for windows subjected to the external flames from the identified façade fire scenario. The thermal loads evaluated from the fire are applied to the window structures to estimate their failure times. Two window casement configurations, closed and tilted-in, are investigated numerically. Then, a thermomechanical analysis of the window is addressed for each casement configuration. The modelled failure times are compared with those used in the general fire development model and from the observations. The good correlation that is observed, regardless of casement configuration, justifies the use of a simplified criterion for window failure in CFD fire models. [ABSTRACT FROM AUTHOR]

This paper presents the combustibility and thermal stability of an intumescent coating system, which incorporates rice husk ash (RHA) and eggshell as abundant by-products, with two other industrial fillers, namely TiO2 and Al(OH)3. Evaluation was performed using cone calorimeter test at 50 kW m−2 and TGA. Experimental results indicated the influence of fillers on the combustibility properties of coating samples and the decomposition rate of coating materials. The TGA results demonstrated that the addition of RHA and eggshell results in the excess residue weight of more than 35% of the total weight loss. The cone calorimeter test results revealed the coating, which consists of TiO2 and RHA, exerts no effect on fire growth because no ignition is observed. The results proved a remarkable fire resistance of waterborne intumescent coating with the addition of RHA and TiO2 which (1) reduces the total heat release rate (HRR) and heat of combustion; (2) increases the carbon monoxide, carbon dioxide, and smoke yields; and (3) releases the lowest amount of gaseous oxygen released. Consequently, the appropriate combination of hybrid industrial fillers and biofillers has significant influence on the combustibility performance and decomposition of the intumescent coating system. [ABSTRACT FROM AUTHOR]

The article Reconstruction of the Grenfell Tower Fire—Thermomechanical Analysis of Window Failure During the Grenfell Tower Disaster. [ABSTRACT FROM AUTHOR]