construction steel structure design specification request large span roof structure

　　Hainan Steel tells you: construction steel structure design specification request large span roof structure
  1 large span roof structure means span roof structure is equal to or greater than 60m, the choice of the truss, arch frame or other flat structure and grid, net shell, cable construction and cable-membrane structure and other space construction.
  
  Impact on the internal forces generated 2, large span roof structure should consider the deformation member, the support structure displacement, boundary conditions and temperature variations; the same can be used to adapt the deformation of bearing structure according to the specific circumstances to release additional internal forces.
  
  3, there is a crane hanging trusses, deflection by permanent and variable load standard value calculated allowable value of 1/500 span advisable, when calculated according to the value of the variable load standard advisable 1/600. No suspension for crane trusses, allowable value of deflection by permanent and variable load standard value calculated advisable span 1/250; when there hanging ceiling, allowable value of deflection value calculated according to standard variable load desirability span l / 500 .
  
  4, large span roof structure book member forces greater or dynamic load is large, its node should use high strength bolt friction type of convergence (excluding tubular structure) Hainan Steel.
  
  5, long-span roof structure should be lifting stage checking, selection and hanging position and other lifting program should be determined by calculation, in order to ensure the strength of the roof structure of each installation stage and all stable.