In this study, 29 reinforcement concrete short beams were tested under two symmetrical concentrated loads up to failure. The main objective of this research was to study the effect of vertical and horizontal web reinforcement and shear span to depth ratio "a/d=1.0, I .5,2.0" on concrete shear strength "V„ " and ultimate shear strength "V„". All beams had the same dimensions and the same tension and compression longitudinal reinforcement. The test results are compared with predictions based on the AC1 building code equations, the CIR1A guide equation, and the modified CIRIA equation. A proposed equation is studied and its prediction values are examined with the test results. Test results indicate that the vertical web reinforcement improves the ultimate shear strength for the tested short beams whatever the shear span to depth ratios. The horizontal web reinforcement also improves the ultimate shear strength but depending on the decrease of shear span to depth ratio "a/d" from 2 to I. The decrease in shear span to depth ratio "aid" between 2 and I showed a considerable increase in concrete shear strength "V„".
KEYWORDS : Shear strength, short beam, web reinforcement, shear span, effective span.