Optimization of frame structures with possibility оf emergency actions
The purpose of the research was to develop the method for optimizing the plane steel frames on the discrete sets of parameters with possibility of emergency actions. The search for the solution was carried out using genetic algorithm. The computational scheme included the following main steps: finding the optimal embodiment taking into account the conditions of normal use of the building; performing calculations of this object in the static and dynamic formulations in the assumption of local damages with the estimation of dynamic coefficient for each considered emergency action; optimal design of the construction with the calculations of the damaged rod systems in a quasi-static formulation using the obtained dynamic coefficients. The analysis of the transient dynamics was executed in the physically and geometrically nonlinear formulation using the associated flow rule. Calculation in the static formulation was implemented within the framework of the deformation plasticity theory with the account for rods of the influence of normal forces on bending. The example of optimal synthesis of the three-span plane frame with the fast damages of any of its column supports was considered. The proposed methodology can be recommended for use in the design of buildings and structures with high level of safety.