Shear Behavior Of RC Beams Reinforced By Steel Fiber Ferrocement Mortar

Reinforced concrete structure is common among civil engineering. Much attention has been directed toward the existing reinforced concrete structure of repairing and strengthening, and it gradually became an important branch of civil engineering. Those buildings with age, using of the age-old, problems of structure design and construction, changes of operating requirement, the disastrous effect of fire etc, would face reinforcing and repair problems. Therefore, various approaches such as structure member strengthening with R.C, externally bonded steel frame, externally applied prestressing and increasing supporting have been employed.Structure member strengthening with steel fiber cement mortar which is use the adding appropriate steel fiber to reinforce cement mortar is a new kind of strengthenting method.It has the advantages of simple construction, convenient, less space occupied and has better durability, fire resistance, tensile strength and elongation, etc than normal mortar, which is suitable for strengthening under various conditions. The foreign experimental study indicates it can be applied in repairing and strengthening engineering. For the domestic study of this method, especially on the shear bearing capacity of the experimental research, need further research.Based on the comparison of the shear test about two general beams and four beams strengthenting with steel fiber cement mortar, the work presented in this paper focuses on several aspects of the following: analysis of the failure form, inclined cracks, deflection and strain development of the experimental beams; the effects of different shear span ratio on shear resistance capacity, failure types, stiffness and crack distribution of the strengthening; comparison reinforcement effect of beams subjected to one-off load and secondary load.According to the analysis of failure mechanism for strengthening beams in building codes and experimental data,some empirical formulas was presented to predict the shear resistance capacity of beam strengthenting with steel fiber cement mortar. In addition, finite element analysis software for nonlinear finite element analysis was used to validate the test results.