MINIMUM REINFORCEMENT IN RC BEAMS
SUMMARY It is commonly agreed that before failure the RC structure must give a warning by cracking and visible deflections. This constitutes the requirements for the minimum reinforcement ratio. Research results suggest that minimum reinforcement ratio is member size dependant. The exact tendency is, however, not clear. In the lack of experimental data, extrapolation of member size dependence beyond the tested size range often takes place. Considering this situation, extensive test series on beams with minimum reinforcement ratios are initiated, varying the member depth in a wide range. In this paper preliminary test results are discussed. They show that the minimum reinforcement ratio of small beams may be reduced, with respects to standard provisions. Further tests on beams with lower reinforcement ratios and more brittle concrete should permit a formulation of member size dependence law for minimum reinforcement ratio.