This paper has already examined the corrosion condition of space truss for welding hollow ball in a swimming pool that is bulit twenty years ago,obtained the average corrosion thickness of bars and the conditon of anticorrosion paint,then analyzed the reasons for the damage of anticorrosion paint and effect of anticorrosion paint which has been painted again.

The paper,from a view of the optimized design,has made a plain analysis on the ratio nality of rust and corrosion resistance for steel sluice gate surface and computerized the weight pro protion of the surface among that of the whole arched steel sluice gate.