Behavior Research Of Whole Steel Frame In Fire

Along with economical development, steel structure is used more and more widely because of its many merits, such as high stiffness,low weight,easily installed and so on. Meanwhile, the number of fire-occurrence and the loss because of fire are increasing. Function of construction is to support loads with the whole structure, so whole structure does not ruined when only a single component ruined. Whole structure is still able to support loads because inner stress will redistribute. It is necessary for steel structure to compute its capability of fire-resistance using whole structure as the object. Taking whole structure as the object, on the basis of ANSYS, Using structure fire-resistance design method that based on the computation, this thesis does the following researches:Firstly, develop a simplifying model. It is reasonable for simulating the relationship of different components to take whole structure as the object. And solution scope becomes huge. In order to limit solution scope, the thesis develop a simplifying model according the studies of the effect that part fire plays on the adjacent area and the whole structure. Secondly, study steel structure in fire with different parameters. Considering the effects of different restrictions playing on whole structure, it takes two connection methods to simulate steel structure in fire. Carrying on the quantitative evaluation analysis with the beam protected and the secondary beam unprotected, get the effects that whole structure is in fire when protected in different ways. Researching mechanics performance when reinforced concrete is acted by temperature load, propose layered reinforced concrete model that will apply in Industry.Thirdly, verify computing model and method. Temperature distribution along the high section is nonuniform. However, temperature grad plays an important part in reviewing mechanic performance of beams in fire with different restriction. It is the first time to perform the experiment and simulation for composite slab–beam in local fire and deduce thermal parameters that will needed to carry on simulation in specific fire condition with"Reverse Method"(namely according to measured temperature to deduce thermal parameters, such as heat conduction coefficient , radiate coefficient and convection coefficient). Finally, simplify the usage of software-ANSYS. In order to make the software used easily and adapt the actual project, the thesis develops the commercial software-ANSYS. So engineers and technicians will take full use of it.