Experimental Research On Seismic Behavior Of Reinforced Concrete Columns Combination Rehabilitation With Bonded Steel Angles And Carbon Fiber Reinforced Polymer Sheet

It is a new form of reinforcement for concrete structure to strengthen them with combination of bonded steel angles (BSA) and carbon fiber reinforced polymer sheet(CFRP) ,which must be proved safe and functional in rehabilitation and strengthening of concrete structure .Based on this purpose, Seven reinforced concrete columns strengthened with combination of bonded steel angles and carbon fiber reinforced polymer sheet under cyclic loads have been conducted to investigate the seismic behaviors. The research focused on such a few aspects as shown below.Seven reinforced concrete columns strengthened with combination of bonded steel angles (BSA) and carbon fiber reinforced polymer sheet (CFRP) under cyclic loads have been conducted to investigate the seismic behaviors. Manufacture of the specimen, the whole experiment process and especially concerning phenomena are expounded. The difference of strengthening methods in seismicity is decided by their comparison while parameters influence on members hysteresis, curve shape , elastic rigidity and ductility are all analyzed by hysteresis curve and curve shape. The results demonstrate that there is a remarkable improvement in ductility, energy dissipation and the load-carrying capacity of flexural-compressive .concrete columns strengthened with combination of bonded steel angles (BSA) and carbon fiber reinforced polymer sheet (CFRP) compared with un-strengthened columns. Furthermore, seismic behaviors of combined strengthened columns are also improved compared with only strengthened by externally wrapped angle steel.Based on confirmation of stress-strain relationship model of steel and core concrete subjected to cyclic loads, theoretical analysis is made on monotonous curve and P-â–³ hysteresis curve of steel tube concrete flexural-compressive members with rectangular section. P-â–³ hysteresis curves obtained from this agree well with computational results. Furthermore, the influences of such parameters as axial load ratio, re-strengthening amount of BSA and CFRP, compression strength of concrete on P-â–³ hysteresis curves are all analyzed based on load-displacement monotonous curve obtained from numerical computation.