Diagonally reinforced coupling beams (1972)
AuthorsBinney, J. R.show all
A previous investigation by Paulay¹ at the University of Canterbury cast doubts on the ability of coupling beams with an L/D ratio of 1.5 or less, to perform satisfactorily in a coupled shear wall system. A theoretical study of the behaviour of coupled shear walls indicated that a ductility of at least twelve was required in the critically situated beams. The conventionally reinforced coupling beams could not attain this ductility, particularly at loads approaching the theoretical ultimate. A system of diagonal reinforcement for the beams was developed in an effort to resist the load by forces within the steel only, hence enhancing the ductility. By testing one conventionally reinforced beam and three diagonally reinforced beams it was hoped to compare their behaviour. It was especially desired to establish any improvement of the ductility and load retention ability under repeated cyclic loading. A comparison was made between theoretical and experimental values for the stiffness and elongation of the beams. This gives some indication of the predictability of beam and coupled shear wall behaviour.