Study on Fire Trace Characteristics of Paper Gypsum Board

As a typical building material, gypsum board is an effective carrier for recording the occurrence and development of fire. Therefore, studying the trace characteristics on the gypsum board has great reference value for indoor fire investigation. This topic adopts the method of macroscopic analysis. By controlling the specifications of the oil pan and the distance from the wall surface of the gypsum board, the fire trace characteristics of the gypsum board under different flame strength conditions are observed and recorded. Based on this, the fire field temperature data is analyzed and compared. Therefore, the relationship between the fire mark characteristics of the plasterboard and the flame position and flame intensity is explored. The results show that the oil pan fire with a size of 20 cm x 20 cm x 5 cm will leave a corresponding trace of heat on the wall of the gypsum board when the distance between the edge of the flame and the wall of the gypsum board is within about 2.5 times the flame radius. Under the condition that the adjacent temperature is lower than 300 °C, the surface of the gypsum board is mainly characterized by coking, and the fire marks are kept on the surface protective paper; when the temperature of the fire reaches 400 °C~500 °C, the protective paper starts to be in the form of debris. When the rupture fell, it was observed that the gypsum board core had a crack of the turtle; the gypsum board completely destroyed the temperature at about 900 °C. Along the distance from the fire point, the gypsum board showed changes in the central round spot, trumpet-like marks, concentric elliptical marks and U-shaped marks. This paper compares and summarizes the influence law of gypsum board fire marks and fire conditions, and provides a reference for the related fire site investigation work in the future.