scholarly journals Fire Safety Assessment of Epoxy Composites Reinforced by Carbon Fibre and Graphene

2020 ◽  
Vol 27 (5) ◽  
pp. 619-639 ◽  
Author(s):  
Qiangjun Zhang ◽  
Yong C Wang ◽  
Constantinos Soutis ◽  
Colin G. Bailey ◽  
Yuan Hu

Abstract This paper presents a coupled numerical investigation to assess the reaction to fire performance and fire resistance of various types of epoxy resin (ER) based composites. It examines the fire response of carbon fibre (CF) reinforced ER (CF/ER), ER with graphene nanoplatelets (GNP/ER) and CF reinforced GNP/ER (CF/GNP/ER). Thermal, physical and pyrolysis properties are presented to assist numerical modelling that is used to assess the material ability to pass the regulatory vertical burn test for new aircraft structures and estimate in-fire and post-fire residual strength properties. Except for the CF/GNP/ER composite, all other material systems fail the vertical burn test due to continuous burning after removal of the fire source. Carbon fibres are non-combustible and therefore reduce heat release rate of the ER composite. By combining this property with the beneficial barrier effects of graphene platelets, the CF/GNP/ER composite with 1.5 wt% GNP and 50 wt% CF self-extinguishes within 15 s after removal of the burner with a relatively small burn length. Graphene drastically slows down heat conduction and migration of decomposed volatiles to the surface by creating improved char structures. Thus, graphene is allowing the CF/GNP/ER composite panel to pass the regulatory vertical burn test. Due to low heat conduction and reduced heat release rate, the maximum temperatures in the CF/GNP/ER composite are low so the composite material retains very high in-fire and post-fire mechanical properties, maintaining structural integrity. In contrast, temperatures in the CF/ER composite are much higher. At a maximum temperature of 86 °C, the residual in-fire tensile and compressive mechanical strengths of CF/GNP/ER are about 87% and 59% respectively of the ambient temperature values, compared to 70% and 21% respectively for the CF/ER composite that has a temperature of 140 °C at the same time (but the CF/ER temperature will be higher due to continuing burning). Converting mass losses of the composites into char depth, the post-fire mechanical properties of the CF/GNP/ER composite are about 75% of the ambient condition compared to about 68% for the CF/ER composite.

2019 ◽  
Vol 37 (3) ◽  
pp. 257-272 ◽  
Author(s):  
Chenkai Zhu ◽  
Jingjing Li ◽  
Mandy Clement ◽  
Xiaosu Yi ◽  
Chris Rudd ◽  
...  

This study investigated the effect of intumescent mats (M1 and M2) with different compositions on the post-fire performance of carbon fibre reinforced composites. The sandwich structure was designed for composites where M1 (carbon fibre reinforced composite-M1) or M2 (carbon fibre reinforced composite-M2) mats were covered on the composite surface. A significant reduction in the peak heat release rate and total heat release was observed from the cone calorimetric data, and carbon fibre reinforced composite-M1 showed the lowest value of 148 kW/m2 and 29 MJ/m2 for peak heat release rate and total heat release, respectively. In addition, a minor influence on mechanical properties was observed due to the variation of composite thickness and resin volume in the composite. The post-fire properties of composite were characterised, and the M1 mat presented better retention of flexural strength and modulus. The feasibility of two-layer model was confirmed to predict the post-fire performance of composites and reduce the reliance on the large amounts of empirical data.


2012 ◽  
Vol 518-523 ◽  
pp. 1269-1272 ◽  
Author(s):  
Liang Yi ◽  
Jie Chen

The aim of this work is to study the burning characteristics of coach fire. With application of computational fluid dynamics (FDS software package), coach fires caused by arson are simulated under different ventilation conditions. Variation of heat release rate (HRR) and distribution of temperature are analyzed. Peak heat release rate of coach fire caused by arson in passenger carriage can reach about 24 MW and maximum temperature in the carriage is over 1000 °C. Results of this study can be referred for fire protection and rescue design of coach.


1992 ◽  
Vol 18 (3) ◽  
pp. 255-272 ◽  
Author(s):  
Vytenis Babrauskas ◽  
Richard D. Peacock

2001 ◽  
Vol 25 (5) ◽  
pp. 203-207 ◽  
Author(s):  
P.A. (Tony) Enright ◽  
Paul Vandevelde

2007 ◽  
Vol 334-335 ◽  
pp. 737-740
Author(s):  
Russel J. Varley ◽  
Andrew M. Groth ◽  
Kok Hoong Leong

This paper presents results of a study carried out to evaluate the effects of an organomodified nanoclay, either on its own or in combination with a polyimide, upon the fire performance of a commercially available nylon. The fire performance, as determined using cone calorimetry showed that up to 40% improvement in the peak heat release rate could be achieved at addition levels of only around 5wt% of nanoclay. The level of improvement was shown to be strongly dependent upon nanoscale dispersion with a more highly exfoliated morphology, as determined using transmission electron microscopy, which showed a greater reduction in the peak heat release rate compared to a more ordered intercalated structure. Investigation of the mechanism of fire retardancy showed that the reduction in the heat release rate is due to the nanoclay reinforcing the char layer which prevented combustible products from entering in to the gaseous phase. Generally, though, the time to ignition is unaffected by nanoclay additions. The addition of the polyimide to the nanoclay reinforced nylon was inconclusive showing little evidence of further improvements in fire performance.


2012 ◽  
Vol 170-173 ◽  
pp. 2535-2540 ◽  
Author(s):  
Li Jun Li ◽  
Zhao Tong Hu ◽  
Qiang Liu

With the rapid development of the highway industry, the steel structure as the main Long Span Bridge build more and more, the highways are carrying more and more traffic than before and vehicle fires are becoming more frequent. This paper, (which is based on previous literature on the behavior of fire, and the main research method of fire heat release-rate) proposes a mathematical model for the heat release-rate of highway fires. Using the fire numerical simulation software FDS to do an analysis of the temperature field of an open space formed by a 300 mw heat release-rate reveals that the maximum temperature decrease is non-linear when the height increase.


2021 ◽  
Vol 35 (3) ◽  
pp. 14-22
Author(s):  
Ho-Sik Han ◽  
Sun-Yeo Mun ◽  
Cheol-Hong Hwang

To improve the reliability of safety assessments in domestic performance-based designs (PBDs), the problem of the input parameters being dependent on fire-simulation users was quantitatively analyzed. Thus, the results of statistical analyses of domestic PBD reports evaluated over the last 5 years were examined. It was determined that the uncertainties of the input parameters might have a relatively larger influence on the statistical deviations than the measurement uncertainties. Accordingly, a sensitivity analysis was performed by considering the statistical deviations of the input parameters that could greatly influence the prediction results of visibility, which are important for the available safe egress time. The main results were as follows: a large change in visibility was observed owing to deviations of the heat release rate and soot yield. Based on this study, it is expected that more accurate results can be obtained if the objectivity of input parameters determined by user dependence can be secured in domestic PBDs.


2021 ◽  
pp. 1420326X2110348
Author(s):  
Jiaxin Li ◽  
Yanfeng Li ◽  
Junmei Li ◽  
Quan Yang

Blocking the tunnel portal is one strategy in railway tunnel firefighting. In order to evaluate the effect of tunnel portal sealing ratio on fire behaviour, Fire Dynamics Simulator (FDS) was used to simulate tilted tunnel fire with different slope angles varying from 0% to 5%, heat release rate varying from 10 to 50 MW and sealing ratios varying from 0% to 75%. Results show that the experimental data of the temperature distribution inside the tilted tunnel were in good agreement with the simulation results. Moreover, the ceiling temperature rise decreases along the tunnel with the increase of the tunnel portal sealing ratio at initial stage and then tends to stabilize because of less oxygen supply when the heat release rate is relatively large. The maximum temperature rise decays exponentially along the tunnel ceiling with distance. The current model for temperature decay beneath the tunnel ceiling was proposed to be modified by taking the tunnel entrance sealing ratio into account. The predictions by the modified model agree well with the experimental measurement. The results could provide practical information and knowledge in ventilation system design and emergency evacuation for inclined railway tunnels.


Sign in / Sign up

Export Citation Format

Share Document