Evaluation of stability design of flat-bottomed cylindrical steel silos

The newly issued Chinese code for design of grain steel silos is compared with the corresponding (European) codes in details such as loads on silos walls and designs for wall stability. Particular (attention) was paid to the imperfection sensitivity of cylindrical shells, effects of internal pressures and manufacturing quality. Parametric studies indicated that for concentric filling/discharging silos (H/D=(1.5～)3.0, D= (5～40()m),) the horizontal wall pressures at the bottom of the silos according to the Chinese code, without considering load factors, are greater than those in the European code, white the axial compression being 60% or so. In contrast to the great difference of the silo wall loads, designs of silos in term of wall thickness, (agree) well with those based on the European code for silos with high manufacturing quality and (subject) to the same load combinations. The differences of the wall thickness are within 20%. Silos (designed) according to the Chinese code are generally economic (thinner wall). Rigorous numerical analyses of a typical (example) silo (H/D=1.5, D=30()m) show that economy is sometimes accompanied by reduction in safety.