This study manufactured beam-slab beam with reinforced concrete, conducted flexural and shear reinforcement according to kinds of reinforcement and position, examined the reinforcement effect and end restraint and obtained the following conclusions.
1. The test body that is reinforced and does not restrain the end compared with the reference test body shows about 13~47% maximum strength increase while the test body restraining the end indicates about 24~77% increase. In comparison of end restraint conditions, the test body restraining the end shows 6~31% more strength increase than the test body not restraining the end.
2. The test body not restraining the end in stiffness evaluation shows stiffness increase as the layers reinforced and reinforced area by location increase more than the reference test body. Although the test body restraining the end shows more stiffness increase than the reference test body, it indicates higher initial stiffness and lower plastic region stiffness than the test body not restraining the end.
3. According to the result of evaluating softness, the reinforced test body shows 60~79% or so softness decrease than the reference test body.
In comparison of the conditions of end restraint, the test body restraining the end shows about 2~92% softness increase than the test body not restraining the end.
4. In comparison of reinforcing effects with the criterion of reinforced cross-section area, the effect by the increase of reinforced area was not great. In comparison of the conditions of end restraint, the test body restraining the end shows better reinforcing effect by reinforced cross-section area than the test body not restraining the body.
In comparison of reinforcing effects by stiffeners, the carbon tube reinforced test body shows higher reinforcing effect in smaller cross-section area than the fiber sheet.
5. According to the result of all experiments, the test body not restraining the end shows improved strength and stiffness but reduced softness and the tendency of brittle fracture.
However, the test body restraining the end is induced to soft behavior from the brittle fracture resulted from surface delamination.
Therefore, when reinforcement is needed in the bending member, if both the bottom and side of the beam are reinforced and the end is reinforced by restraint, the reinforcing effect will be far greater.