FRP (Fiber Reinforced Polymer) reinforced lightweight concrete structures can offer corrosion resistance and weight reduction effect simultaneously, so practical use of the structures may be expected afterwards. But, to construct the concrete structures using lightweight concrete and FRP bar, one of many important things to be previously investigated is to study bond characteristic between the lightweight concrete and the FRP bar. So, bond characteristics between lightweight concrete and two types of GFRP bar (helically deformed GFRP bar and sand coated GFRP bar) were investigated in this study. To do this study, literature review and bond strength test using a number of bond strength specimens were conducted. As a result, it could be seen that the bond strength of helically deformed GFRP bar and sand coated GFRP bar in the lightweight concrete were 49% and 81%, respectively, for the bond strength of steel reinforcement in the normal concrete.

This study is to understand the structural behavior of flexural member according to the splice length of specimens reinforced by GFRP reinforcing bar. As compared with reinforcement, GFRP reinforcing bar has superior material properties such as non-corrosiveness, light weight, non-conduction, etc. However, GFRP reinforcing bar is difficult to use instead of reinforcement owing to brittle fracture when it failed. Therefore, GFRP reinforcing bar mixed with deformed reinforcing bar were used. A total of 5 specimen was produced and tested and the test main variables are the diameter of tension steel, lap splice length of GFRP reinforcing bar which are for investigating the reinforcement effects. The diameter of tension steel set as D10, and D13 and the lap splice length of GFRP reinforcing bar set as 30db, 45db and, 60db. The results of the experimental test, the specimen with GFRP reinforcing bar proved more reinforcement effect than the one without GFRP tie bar. At the same time, the specimen with tension steel of D13 increased an overall strength more than the one with tension steel of D10. The longer lap splice length showed increase the strength.

The objective of this study is about hollow core slab with GFRP (Glass Fiber Reinforced plastics) Reinforcing bar instead of using deformed bar. This experiment is planed because using GFRP Reinforcing bar instead of tension bar in existing RC hollow core slab will improve not only on the constructability but also on the durability by solving the corrosion of slab. As the result of the experimental study, GFRP Reinforcing bar and additional deformed bar appear to be superior compared to RC hollow core slab in structural ability.