The tensile membrane action of non-orthogonal composite slabs at elevated temperatures

摘要: Abstract In order to generalize the applicability of nonlinear numerical investigation structural behavior slab panels at high deflections, which utilizes tensile membrane action in slabs, meshing such floor systems cannot be restricted orthogonal grids. A separate but related issue is that modelling internal with continuity across their edges has shown way boundary conditions are defined can have a considerable influence on predicted forces various situations. This research investigates behaviour and non-orthogonal composite slabs elevated temperatures by means modelling. With different panel edges, effects deflections identified. In achieve this end, penalty function method first developed allows terms relationships between degrees freedom system’s global coordinates, as opposed conventional binary “free or restrained” choice for individual freedom. either respect axes inclined system, link displacements nodes. easily defines suitable also realistically modelled. In simplified design methods, it often possible divide areas building into rectangular square panels, problem near buildings still exists. thesis attempts begin extend these methods determining optimal small-deflection yield-line failure patterns quadrilateral geometries. Simplified assume enhancement capacity due increases continuously vertical deflection. However, deflection increases, through-depth cracks may not coincide yield lines occur, cause progressive reduction load capacity. Optimizing assumed using plastic work balance method, establishes validates two existing trapezoidal slabs. Further studies determine precise made gradually changing geometrical parameters. A new energy includes dissipation during rebar extension been extended triangular The post-yield-line demonstrated. compares factor performance from method. An reinforcement meshes geometry load-carrying isosceles carried out.