Force Distribution and ductility Behavior of Reinforced Concrete Coupling Beams with Diagonal Reinforcement
Abstract
Beams with coupling force have been designed as
conventional flexure members with stirrups and with some shear
resistance allocated to the concrete are oftentimes will inevitably
fail specially at diagonal areas, hence for beams with coupling
force is recommended that the beams are reinforced with
diagonal systems (bi-diagonal reinforcement). Six object test
coupling beams 400 x 300 x 150 mm have been tested to aim the
target, which is to know the behavior characteristic of
deformation and mode of failure, to know the placement influence
of diagonal reinforcement at coupling beams. Result of research
indicate that behavior 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. The proposed
method of analysis of reinforced concrete coupling beams based
on the equilibrium of forces of triangular half of the beam at
failure gives a satisfactory prediction the distribution of force in
the main bars. The behavior of coupling beams in shear (diagonal
splitting) mode of failure is represented in mathematical model.