Nine two-span continuous reinforced concrete beams with point loads 4.5' on each side of the center reaction were tested. This tested the effects of both longitudinal and transverse reinforcement on the shear strength of the beams. Results of testing the beams showed the effects of maximum shear and moment occurring at the center reaction.
Three sets of three beams were constructed to examine the affect varying the amount of longitudinal and transverse reinforcement had on the flexural and shear strength of a beam. Within a set of beams, the longitudinal reinforcement consisted of either No. 3, 8, or 10 reinforcing bars.
Transverse reinforcement was consistent for each set of beams. The first set of beams did not have any shear reinforcement and were used to study the effects of longitudinal reinforcement on the shear strength of a beam. The second set of beams considered the effects maximum transverse reinforcement spacing has on the shear strength of a continuous beam. The third set of beams was used to examine whether further increases in transverse reinforcement were sufficient to preserve the shear strength when the flexural steel yields.
Specimens with No. 3 longitudinal bars explored the flexural characteristics of continuous beams with minimum longitudinal reinforcement ratios. Specimens with larger longitudinal reinforcement were used to evaluate the effects of more longitudinal reinforcement had on the shear strength and moment distribution. A test was performed to determine deformed welded wire fabrics ability to be used as transverse reinforcement.
Measured values from testing were compared to calculated values from ACI 318-05 Building Code Requirements for Structural Concrete, which provided conservative results in both shear and flexural capacity when shear reinforcement existed.