Economical choice of columns
Existing stables are being extended with a canteen of approx. 54 m2 a passageway of approx. 31 m2 with a toilet of approx. 3 m2, an office of approx. 28 m2, washrooms of approx. 16 m2. In front of the facade, the roof of the whole is carried by an oak truss, in the facade by a steel truss and roughly halfway along the side walls by another steel truss. The steel trusses are connected by steel beams, creating a space frame. The roof pitch is 20°. Because many windows are planned in both the front and side walls, no wind bracing is installed there. The columns are therefore fixed at the base.
The deformation limits govern the sizing of the structure. Suppose the x-direction runs parallel to the front wall and the y-direction perpendicular to it. Giving one pair of short columns high stiffness in the x-direction and another pair high stiffness in the y-direction produces an economical structure. The other columns can then be designed relatively light. Meeting the building regulations (in the Netherlands, the Bouwbesluit) still leaves many variables that can be optimised for an economical result.