Effective Span

Summary

Effective Span - The effective span is used to calculate the flexural resistance of an element.

Technical Information

Depending on the location of the span in question the effective span (Leff) is a function of the slab thickness, the width or diameter of the supports and the distance between the centre of the supports. The effective span decreases as the width of the support slab increases.

In a pile-supported slab, a pile head is often situated on top of the pile, which increases the width of the slab support hence reducing the effective span. This will reduce the maximum bending moment induced in the slab.

Effective spans are not applicable to the design of ground supported slab.