One-Way Reinforced Concrete Slabs

Abstract

The simplest routine structural element for illustration of design provisions in the Code is the one-way slab. A one-way slab is defined for purposes of this book as a flexural member with depth small relative to other dimensions, supporting (gravity) loads applied normal to and directly over its surface, spanning in one direction between parallel supports, and reinforced for flexure in that direction only. For purposes of analysis, one-way slabs may be restrained to any degree at the supports or may be unrestrained. A number of Code provisions refer to “flexural members,” which include one- and two-way slabs, beams, girders, footings, and, where bending exists with the axial load, walls and columns. In general, when the Code provision is intended to apply to one-way slabs, the term will be used in the sense of the definition herein. For example, the Code requires stirrups in most beams, but specifically exempts slabs and footings from the requirement (Section 11.5.5.1). Where the Code term “structural slabs” is used, as in the provision that the minimum reinforcement in the direction of span shall be that required for temperature and shrinkage (Sections 7.12 and 10.5.4), the requirement applies to both one- and two-way slabs as herein defined. In this book, one-way slabs and beams are discussed separately. Beams are defined herein as one-way flexural members designed to support concentrated line loads such as slabs, girders as one-way flexural members designed to support concentrated loads such as beams. Either beams or girders or two-way slabs may be utilized as primary members of a frame. For design of beams, see Chapter 9. For design of two-way slabs, see Chapters, 5, 6, and 7.