Research On Temperature Distribution And Fire Resistance Performance Of Composite Deck Slabs

High temperature caused by fire may damage the building severely, even make it collapse. In order to make sure that the building has enough fire resistance capacity, the fire resistance of the building structures must be analyzed.In recent years, profiled steel sheeting-concrete composite deck slab (hereinafter for short: composite slab) has been developed and widely applied in engineering field, Steel composite slab,as a very reasonable structure where steel and concrete aterial strength are completely utilized, has quick construction, good ductility and higher anti-earthquake capacity.At the present time,special method is still ambiguous in criterion, and it also can't meet the need of engineering development. Therefore, a thorough study of fire resistance and fire resistance design method of composite slab has great theoretical value and practical significance.Firstly in this paper, analyzes the thermal and mechanical properties of normal concrete and structural steel at elevated temperatures for composite slab are presented. The thermal properties and the stress-strain relations of steel and concrete in composite slab under high temperature are determined.Secondly analysis of temperature distribution of composite slabs under fire. The temperature field in composite slabs is to be determined before fire resistance of composite slab must be studied. Based on the thermal transmission, The temperature distribution in composite slabs under fire is analyzed by using FEM(Finite element method). The transient temperature contours and curves varying with time acquired from numerical simulation and experiment are quite identical. It is showed that the calculation model is reasonable and the method is correct and feasible. Meanwhile, 2D and 3D FEM models of the composite deck slabs are built. The optimal calculation model based upon the comparison of calculation results of two different simulative models is obtained; references can be supplied for the temperature distribution of member under fire.At last, the fire-resistance performance of simple-support slabs is studied, By using ANSYS program, the temperature filed of composite slabs subjected to the standard fire has been done, and then the result of temperature field was introduced into the structure program by using the coupling program of ANSYS, the effect on the fire resistance of simple-support slabs has been discussed and the result was compared to the result of the experiment. The simulation result and experiment result show agreement on the whole. It testifies that the simulation result is right and result is accurate and reliable.