| 摘要 |
The framework for casting a concrete staircase or steps in-situ has a corrugated base 1 with trapezoidal corrugations running along its length, side walls 3, and a number of risers 4 running between the side walls and across the base, the frame forms part of the finished stairs when concrete is poured in and has set. The side walls and base may be made from sheet steel between 0.5 to 3mm in thickness. The base may be formed from corrugated deck, having preferably between three and six corrugations, with a height between 2 to 10% the width of the stairs. The dividing walls may be sheet metal and have tabs which engage with slots in the side members. The underside of the base may have fire resistant board placed over it to conceal the corrugated base. |
