Preliminary Stress Analysis on Beam Surface As A Result of Char Expansion In A Fire Exposed Intumescent Coating

Intumescent coating is one of the most popular fire-retardant methods being used nowadays. During a fire event, the coating will expand to create a fire insulation layer on the structure it is protecting called char. When the coating expanded however, stress is created on the char. The objective of this project is to analyze the stress created on the beam-char interface. First, the preliminary 1- dimensional analytical calculation was done to predict the behavior of stress. The types of loading considered in the analytical calculation were uniaxial load and buckling. For 3-dimensional case, the expansion was simulated in ANSYS. The analytical calculations showed that the middle span of the interface experienced high stress. It was observed that the longer the interface, the higher the stress would be. It was also found that the beam interface was in tension while the char interface was in compression. This was parallel with the results obtained by using ANSYS in the 3-dimensional analysis. From the buckling analysis, it was found that the critical load before the buckling can happen is higher when the length of the beam-char interface is longer. Hence it was recommended to apply the intumescent coating in stripes to reduce the interfacial length.