Precast concrete stair flights and landings are a common form of construction. As individual elements they are inherently robust, and as the spans of such elements are relatively small, flexural or shear failures are very rare.
In the event of an occurrence such as fire or the failure of lifts, stairs often provide the only practical means of escape for the occupants of a building. It is vital therefore, that stairs
remain available and useable under extreme conditions without suffering progressive
collapse. One method through which this can be achieved is the anchoring of the individual elements into the structure.
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