DISCUSSION ON THE IMPROVING COEFFICIENT FOR BEARING CAPACITY OF SPIRAL REINFORCEMENT COLUMN UNDER AXIAL COMPRESSION

摘要

In the "Code for Design of Concrete Structure" (GB50010-2002), the improving coefficient for bearing capacity of spiral reinforcement column under axial compression is mainly obtained by experiments, but it shows a lack of systematicness and theoretical property. In the paper,the twin shear unified strength theory, which considers the influence of intermediate principal stress σ2 and can be applied to various materials under complex stress state, is adopted to analyze the reason that the bearing capacity of spiral reinforcement column under axial compression is enhanced.The bearing capacity formula of spiral reinforcement column based on unified strength theory is proposed. Compared with the formula of the code, the bearing capacity formula of spiral reinforcement column under axial compression based on unified strength theory has more systematicness and theoretical property, and the calculated values are closed to the experimental values. So the modified formula can provide more applicability and economy for practical engineering.