Hello, today I am introducing to you an excel spreadsheet program specially created to help design one way continuous reinforced concrete slabs. A one way slab is a slab in which its length divided by its breadth is greater than or equal to 2. However, a slab with length/ breadth ratio of not less than 1.5 can still be designed as one way. The spreadsheet named RCC31 designs to BS 8110 and it is free. It was developed by the Reinforced concrete council and its been around for a while.
You can download this spreadsheet by clicking the link below.
At the top of the spreadsheet is the title section. This is
where you input title data for the slabs being designed. You can input names of
the project and client as well as other title information.
Below it is the materials section where you can input
material strength properties of concrete and steel. Including factors of
In the span section you can set slab span and thickness,
note the units.
Under loading pattern you set factor of safety values for
dead and imposed load.
At the supports section, you can set 3 types of supports,
including, kinife, cantilever and encastre.
A look at the loading section, and you will realize the spreadsheet can handle up to six slabs at once.You can input dead imposed and point loads n this section. Again note the units in which the loads should be provided.
Now all what I have explained so far is within the MAIN tab of the spreadsheet. To see the calculated span and support moments, click the ACTIONS tab.
To see calculated and design steel reinforcements, click the SPANS tab.
In the SPANS tab notice that top and bottom reinforcements
are provided in the left right and center for each span designed. However in
your detailing you can rearrange reinforcement for example, in each span you
can pick the highest designed bottom reinforcement occurring either in the
left, centre or right end and use as general for the whole span.
If design fails in maximum spacing ( max S), reduce size of