Abstract: In order to compare the fire protection and heat insulation effects of different materials of fire barriers in cable tunnels and provide a reference for the selection of fire barriers, this paper first tests the combustion and mechanical properties of four typical fire barriers used in tunnels, and then builds a real test platform to simulate cable tunnel fire, and conducts comparative tests on the fire protection effects of different barriers. The results show that the inorganic calcium silicate board is incombustible, but its mechanical properties are the worst. In the true type test, the partition plate breaks under three kinds of fire power, and can not play a role in fire protection after breaking; Inorganic glass magnesium plate is incombustible. In the true type test, the mechanical properties become worse under the fire power of 300 kW and 400 kW, the upper part of the fire source of the partition is deformed, and the fire prevention effect is poor; The organic pultrusion board is combustible, and the back fire surface of the partition will be ignited under the fire source power of 300 kW and 400 kW, which cannot play a role in fire prevention; The organic molded plate is difficult to burn. In the true type test, under the power of three fire sources, the heat insulation effect is good, the back fire surface will not be ignited, and the mechanical property is good, which can play a good fire protection effect.

Key words: cable tunnel fire, fire barriers, combustion properties, mechanical properties, fire protection effect