Abstract:

Sixteen specimens were tested under low cyclic loading to analyze the shear distribution between the shapesteel and the concrete in transfer columns as well as the distance from the shear action spot of shape steel to the col-umn bottom.Then,the shear damage of concrete under low cyclic loading was investigated.The results show that(1) the distance from the shear action spot of shape steel to the column bottom is mainly affected by the shape steelratio,the extension height of shape steel and the axial compression ratio; (2) the shear force resisted by shapesteel increases with the shape steel ratio; (3) with the increase of extension height of shape steel,the shear forceratio decreases first and then increases; (4) the distribution coefficient of shear force slightly decreases with theincrease of axial compression ratio; (5) the distance from the shear action spot of shape steel to the column bot-tom,which is slightly affected by the shape steel ratio,increases with the decrease of axial compression ratio,andincreases first and then decreases with the increase in the extension height of shape steel; and (6) the shear forceof shape steel reacts upon the central area of concrete section and leads to tension stress,which accelerates thedamage of concrete.At the same time,the damage of concrete results in the degradation of shear capacity and theshear enlargement of shape steel.This interplay between concrete damage and shear force of shape steel ultimatelyleads to the accumulation of concrete damage and the failure of transfer columns.

Key words:  steel reinforced concrete, reinforced concrete, transfer column, shape steel ratio, extension height, axial compression ratio, shear behavior