The present work studies the flexural behavior of a new type of staying in place (SIP) forms which could be used for beams in future buildings. Six specimens were prepared with (SIP) and tested under four points bending loads. The first group contains two specimens; both of them are supplied with inverted FRP U shape strips to improve the bond between FRP form and concrete. The first specimen contains a PVC tube without reinforcing while the second specimen contains a PVC tube wrapped by three layers of GFRP sheets. The second group contains two specimens; both of them are prepared with upper FRP hooks to improve the bond between FRP form and concrete. Also, the first specimen of the second group contains a PVC tube without reinforcing while the second specimen contains a PVC tube wrapped by three layers of GFRP sheets. The third group contains two specimens; both of them are prepared with upper FRP hook and have three layers of CFRP in the bottom inner face of the form. Both specimens contain unreinforced PVC tube, and the second specimen is prepared with transversal FRP links to improve the bond between FRP form and concrete. The experimental results included ultimate load, load-deflection and load-strain relationships, also; the cracking behavior and failure mode were observed and recorded. The experimental results showed an improvement in the flexural strength of the tested specimens as FRP reinforcement is added to PVC tube or to the form. Also, using FRP hook was the best technique to improve the bond between FRP form and concrete.
Moreover, the tested specimens were simulated numerically using ANSYS (version 15). The ultimate loads according to the numerical simulation were higher than the corresponding experimental results by 5% to 38%. |
