Study On Mechanical Behavior Of Corroded Concrete Filled FRP-steel Tube Structures

Concrete filled GFRP-steel tube, a combination of concrete filled steel tube and GFRP sheet, is composite structure which has many excellent characteristics. GFRP (glass fiber reinforced polymer) has high strength, light weight and corrosion resistance property, etc, GFRP strengthening can effectively improve the bearing capacity of concrete filled steel tube structure and reduce the consumption of construction steel and so that reduce the cost. Compared with CFRP reinforced concrete filled steel tube, GFRP one costs less. More importantly, because lots of developed city distribute in coastal areas, concrete filled steel tube has been widely used in different architectural structures in those cities, which puts forward higher corrosion requirement for the structures. Through the theoretical analysis, experimental test and numerical simulation, this paper discusses the new structure of the axial pressure behavior, corrosion resistance to offer scientific basis for engineering design and structure strengthening.In order to research the effect of GFRP on the corrosion resistance of concrete filled steel tube structure, five specimens of the same size with different strengthening styles were corroded in vary degrees and then tested under the axial compressive loading. The results show that, GFRP provide the excellent protection for concrete filled steel tube structures and effectively improved their ultimate axial compressive load as well.For the purpose of further studying, ABAQUS was used for the investment of the effects of FRP thickness on the mechanical properties and the corrosion resistance of the specimens. On the basis of the consistence of simulated results and experimental data, a developing analysis was performed and the results to showed that local corrosion decreases more the ultimate strength than the overall corrosion in the same corrosion conditions.