Standardised concrete step modules for building prefab. staircase - has riser height side string wing sections of parallelogram shape reinforced with steel flat or bar and bolted together to form flight

摘要

Each step module (21) comprises a tread, riser, and two side sections which form part of the stair string when the flight is assembled. The side sections are of parallelogram form, such that the top and bottom horizontal faces are the dimension of the riser apart. The side string sections (22) are reinforced with steel bar or flat section steel bent and welded to the same parallelogram shape with a bracing bar across the short diagonal. The steps are assembled with bolts (25) in nuts welded to the reinforcement.