Compound Sections, Cellular Beams and Slim Floor Construction

There are additional options available for compound steel sections, cellular beams and slim floor construction.

Compound Sections

An additional bottom plate can be added to the steel beam, where the thickness and width of the plate are specified. Instead of the plate width, a projection distance can be entered. The plate can be central on the beam or be offset to the left or right only.

Cellular Beams

A cellular beam can easily be set up.

If a normal UB or UC is specified initially and the cells are added, the beam is considered to be profiled cut along the length of the web, moved a short distance laterally and welded back together again along the web to create a deeper cellular beam type section. The new beam depth will be dependent on the diameter of the cells and is specified in the start of the calcs.

The cells can be specified as the diameter of the opening (Do) and the spacing (S) and can be entered either in mm or as a ratio of the beam depth. For example, Do could be entered as 0.6 times the beam depth. The spacing is then entered as a multiple of the Do ratio, say 1.8. For a 356 UB, the opening diameter Do would be 0.6x356 = 215mm and the spacing S would be 1.8x215 = 385mm (rounded down from 387mm).

You can specify the distance from the top of the beam to the top of the opening. If no value is entered, it is assumed the opening is central in the depth of the beam.

The Cut Gap is the additional gap allowance between the top and bottom parts of the beam when it is being profile cut, eg, 10mm.

In some situations you may want to fill certain openings, for example those at incoming secondary beams. Enter the distance to the centre of these openings to remove them from the beam as shown above where the openings at 3m and 6m are filled.

You can also enter a value for the clear distance to the start and end of the openings by placing a minus sign in front of these distances - see below where the first 1.4 m of the beam is clear of openings and the beam beyond 8.5m is clear of openings.

Slim Floor Construction

In addition to profiled decking or precast slabs being placed on the top flange of a beam you can design slim floor construction beams where a deeper decking is placed on the bottom flange of a beam. A normal UB or UC section can be chosen from the droplist of sections and an extended plate added to the bottom flange if required, on which the deeper profile decking will sit. There are also a list of Asymmetrical SlimFloor Beams (ASBs) available from the sections droplist to accommodate the slim floor construction.