Bearing capacity of steel tube-concrete-FRP-concrete composite columns
Tao Yi , Zhang Haizhen , Shi Qingxuan , Chen Jianfei
DOI:10.11835/j.issn.1674-4764.2017.02.006
Received July 11, 2016,Revised , Accepted , Available online July 04, 2017
Volume ,2017,Pages 43-49
- Abstract
The sectional form of steel-concrete-FRP-concrete (SCFC) column, as a novel composite column, has a steel tube as the outer layer and a circular FRP tube as the inner layer, and concrete filled between these two layers and within the FRP tube. Considering the confinements from both outer steel and inner FRP layers, the twin shear unified strength theory and force equilibrium condition are utilized to develop an analytical model of bearing capacity of SCFC column. The accuracy of the proposed model is evidenced through being compared with experimental data. The parametrical study is conducted in order to evaluate the confinements affected by the sectional steel proportion, ratio of FRP to steel, ratio of diameter to thickness of FRP and FRP diameter itself. The results indicate that the greater sectional steel proportion, the larger ratio of FRP to steel, and smaller ratio of diameter to thickness of FRP have positive contributions on the confinements of SCFC. The ratio of FRP diameter to steel side length locates between 0.65-0.75 can lead to a better confinement.