Stadium, fitness centre safety factors from steel pipe

Sports, basketball, baseball, ping-pond, badminton are good for our health. And all of them would be our relax ways after work. Thus, it would be a concerned topic for which kind of steel pipe ( ERW steel pipe? SSAW steel pipe?) used in the whole project to build the stadium or fitness centre for those who like these sports.

How much would cost on steel material for demand of steel structure for a general sports stadium building? We can see that gross floor area for sports stadium in Beijing Olympics is 1.69 million square meters, lots of materials are steel among the design. So for every sports stadium, there are various steel would be needed as well as the ERW steel pipe and SSAW steel pipe. For swimming pool, we know there is various steel pipes for the water transportation system. Under this situation, suitable steel pipe like SSAW steel pipe or ERW steel pipe would be necessary as their cost would be lower than the seamless steel pipe.