Study On Thermal Performance Of Commonly Used Fire-resistant Plates At High Temperature

The building fire-resistant board is not only a steel structure fire-proof protection material,but also a kind of wallboards,which is widely used in the cold-formed steel structure.However,the thermal performance of fire-resistant panels and the fire resistance of cold-formed steel walls with build-in sound insulation measures at high temperatures remains to be further studied.Therefore,this paper studied the thermal parameters of fire-resistant panels widely used in the construction field at the beginning.In the density,we applied different heating rates to measure the density of panels.And in order to remedy the shortcomings of traditional thermal conductivity measurement methods,the thermal conductivity is measured by different measurement methods.At the same time,in order to study the equivalent specific heat capacity considering the effect of water migration,experiments and numerical simulation are carried out.Equivalent specific heat capacity was studied by combining the two methods.Secondly,the fire resistance performance of the cold-formed steel wall with built-in sound insulation is measured.The main contents and results are as follows:1.Thermal performance test and theoretical study of commonly used building fire-resistant panels: The gypsum board(including Long brand fire-resistant gypsum board and Knauf fire-resistant gypsum board),glass magnesium board,calcium silicate board and CCA board which are widely used in the construction field were tested for density,specific heat and thermal conductivity.(1)The density of three different fire conditions was tested to investigate the influence of different heating rates on the density of the board;(2)A total of 64 specimens were designed for thermal conductivity test.By using PBD method,one-dimensional transient heat transfer method and lumped heat capacity method,the thermal coefficients of different plates under different fire conditions were obtained;(3)Through the combination of test and numerical simulation,the veneer of five different plates(total of 10 test pieces)was tested.The two-dimensional heat transfer model of the veneerwas established by ABAQUS.By comparing the results of the simulation and the test,the influence coefficient of specific heat capacity migration was obtained.2.Experimental study on fire resistance of different cold-formed steel walls: The fire resistance of four different types of cold-formed steel walls was tested.The test results show that:(1)The wall resistance time(118 mins)using the self-tapping screw fixing method on the main keel is longer than the resistance time(96 mins)of the wall using the pinhole fixing method;(2)The rubber mat sound insulation measures in the cold-formed steel walls can alleviate the "thermal bridge effect" at the vertical keel,and the fire resistance is better than other walls,and the fire resistance time is123 mins;The rubber mat sound insulation measures in the cold-formed steel walls can alleviate the "thermal bridge effect" at the vertical keel,and the fire resistance is the worst one,and the fire resistance time is only 89 mins.