Civil Engineering ETDs

Publication Date



Within the last ten years a considerable amount of research has been conducted to determine the behavior of reinforced concrete deep

structures. The major portion of this recent research has been devoted to deep beams. The results have shown a marked difference in the behavior of deep beams as compared to beams of “normal” proportions. In

this context the word "deep" implies a small span-to-depth ratio. There is not a clear-cut distinction between a "normal-depth" and a deep struc­ture; however, span-to-depth ratios less than ten would suggest deep structures. The difference in behavior between deep beams and normal depth beams would imply there may also exist a corresponding difference in the behavior between deep and normal-depth slabs. One apparent area of deviation in slab behavior may be in the mode of failure. The design of conventional reinforced concrete two-way slabs is normally controlled by its flexural behavior. The shear strength is usually not the governing factor since two-way slabs provide a large perimeter to resist the shear force. As the span-to-depth ratio of a slab decreases, both the flexural and the shear capacities increase. However, the shear strength increases inversely as the first power of span-to-depth (L/d) ratio, whereas, the flexural strength increases inversely as the square of the (L/d) ratio. Therefore it is conceivable that the shear strength of a deep slab could control its design. But, the behavior in shear of reinforced concrete members has not been well understood, therefore limiting the amount of published literature in the area of shear strength of two-way slabs. ultimate strength methods for the design of two-way slabs have been employed increasingly in the last twenty years. However, these methods, such as the yield-line theory, preclude the possibility of a shear failure preceding a flexural failure, increasing the necessity to understand the behavior of deep reinforced concrete two-way slabs

Document Type




Degree Name

Civil Engineering

Level of Degree


Department Name

Civil Engineering

First Committee Member (Chair)

E. J. Rhomberg

Second Committee Member

Roy Linton Johnson

Third Committee Member

Cornie Leonard Hulsbos

Fourth Committee Member