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Design structure:

The cross section of truss structure should be determined according to the calculation of strength and stability. In order to reduce the calculated length of the pressure bar and increase its stability, measures such as adding the redividing bar and supporting bar can be adopted. The joints of the plate-type grid and the double-shell grid made of steel mainly include three forms: the cross plate joint, the welded hollow ball joint and the bolt ball joint. The cross plate joint is suitable for the grid structure of steel bar, bar and joint

The point plate connection shall be welded or high strength bolt connection. Hollow ball joints and bolt ball joints are suitable for the truss structure of steel pipe. The joints of single-layer shell frame should be able to withstand bending internal forces. In general, the steel consumption of the joints accounts for 15 ~ 20% of the total steel used in the whole structure.

Construction and Installation:

The construction and installation methods of grid structure can be divided into two categories: one is the integral jacking method, the integral lifting method and the integral hoisting method assembled on the ground; The other method is bulk loading, strip and block loading and sliding loading.