The Reinforcement of Steel Columns Engineering（钢柱的加固工程）.pdf

The Reinforcement of Steel Columns LAMBERT TALL Ther e may be a need for a steel column to have load- discussion are the residual stress magnitude and distribu- carrying capacity additional to that planned in the original tion. Residual stresses are those internal stresses set up in design. Columns may be reinforced by the addition of ma- a member due to plastic deformations such as those due terial in the form of cover plates, or by changing the resid- to cooling after welding.^-^ Since the residual stresses exist ual stress distribution to a more favorable one by the lay- in the cross section before the application of load, their ing of a weld, or by a method that combines both of these effect is to reduce the load-carrying capacity from that effects. For columns carrying design loads, their reinforce- which it would have been otherwise.^^^^ Equihbrium re- ment is possible and safe. The strength of reinforced col- quires the existence of both tensile and compressive resid- umns is identical for the conditions of reinforced under ual stresses in the cross section (Fig. 3), yet it is only the load and reinforced under no load . The maximum effect compressive residual stresses that contribute to the reduc- of reinforcement is obtained when the reinforcing weld is tion of compressive strength . The magnitude and distribu- as close as possible to the edge of the flange of the base tion of residual stresses in a structural shape is normally shape.