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construction steel structure design specification requires a large span roof structure

Guangzhou Steel news: construction steel structure design specification requires a large span roof structure

1 large span roof structure means span roof structure is equal to or greater than 60m, can be used truss, arch frame or other flat structure and grid, net shell, cable construction and cable-membrane structure and other space construction.

An impact on its internal force 2, large span roof structure should consider the deformation member, the support structure displacement, boundary conditions and temperature changes; at the same time get used to using deformable 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 adopt high strength bolt friction type connection (except pipe structure).

5, long-span roof structure should be checking during hoisting, lifting points and the selected location hoisting program should be determined by calculation, in order to ensure the strength of the roof structure during each installation and all stable. Guangzhou Steel