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Case study Leuven Railway Station
The design of the station covering takes several boundary conditions into account:
visual comfort, the relation with the surrounding buildings, the choice of covering,
acoustics, wind control, optimum use of materials, and minimal cost.
Considering each boundary condition separately yields consistently different
results. Therefore, a singular solution which responds to all the aforementioned
boundary conditions is being sought.
The study of volume and displacement indicators is used to gain an immediate
insight into the possible characteristics of the arches and is a helpful aid in the
research pertaining to the optimum structure (optimum material use and minimal
cost).
The following graph indicates that the total cost price, in this case the cost of
a singular arch, is the result of the cost of the main structure (the arch) on the
one hand, and the covering material (for instance glass or steel decking) on the
other hand. The optimum result in the case of the arch is attained at a very low
slenderness L/H level. Since the cost of the finishing material decreases as the
slenderness increases, the sum of both figures will yield the optimum result.
The various boundary conditions delineate an area in this graph within which the
most favourable structure can be identified. The graph also indicates in how far a
chosen solution deviates from the optimum result.
The volume indicator W specifies the volume of steel necessary to realise the arch
through simple calculation. Exact design calculations can be made from this point
onward.