Force Distribution of Reinforced Concrete Coupling Beams With Diagonal Reinforcement

Abstract

The structural behaviour of reinforced concrete couple shear walls is greatly influenced by the behaviour of their coupling beams. The behaviour of the coupling beams themselves depends on the geometry of the beams and the strength characteristics of the concrete and reinforcement. Behaviour characteristic of deformation and mode of failure at coupling beams that happened is the existence of compression area at diagonal direction coming in contact with tip of force, tension area at opposite diagonal direction which will have crack till split at diagonal area compress, and the beam will attain its maximum load carrying capacity when small portion of the concrete in the compression corners crush. Mode of failure that happened is shear failure. The proposed method of analysis of reinforced concrete coupling beams based on the equilibrium of forces of a triangular half of the beam at failure gives a satisfactory prediction of force in the main bars. The distribution of force in the main bars of the beams at failure is showed using the proposed concept, when the diagonal splitting mode of failure occurs, is tensile. The force varies linearly along the span with a smaller value at he tip of the triangular half of the beam to its full capacity at the support. Although it was not possible to compare the force directly with the experimental result, the observed behavior agrees with the proposed concept. The distribution of force in the bars based on the conventional concept of flexural deformation of reinforced concrete coupling beams differs drastically with the actual behavior.