Optimum Floor Framing System Supporting Largely Spaced Columns

The development of technology and design procedures of modern tall building that
started in 1880s, now reached to an advanced level, particularlywith the use of software
available for design and construction of tall buildings. The sophisticated structural
systems high accuracy is possible to obtain. Besides the main structural system,
selection of an appropriate floor framing system is essential to determine the overall
economyof the building. The efficiencyof buildings using same material with the same
height is measured by the weight per unit floor area of it.
The focus of this project is to analyze the most optimum two-way concrete floor framing
system, supporting largely spaced columns for tall buildings, especially public gathering
buildings. Four types of floor framing systems were analyzed. Optimum in this context
refers to the optimum deflection satisfying the permissible deflection range. Besides,
cost effectiveness with minimum floor thickness fulfilling the head room specified is
also taken into consideration.
The grids of the slabs analyzed are 12m x 12m, 15mx 15m and 18mx 18m, while the
types of floor framing systems analyzed are conventional beam-slab system, flat plate,
waffle slabs and the post-tensioned flat slabs. The conventional beam-slab system acts
as the bench mark for comparison. Computer modeling using STAAD.Pro 2002 was
carried out. Two life load conditions, which are the normal floor and mechanical floor,
with two life load patterns were modeled. The results were analyzed and the most
optimum floor framing system was determined. The controlling parameters in
determining the optimization of the floor framing system are the maximum deflection,
the slab thickness, the floor headroom, the costandthe construct ability of the structure.
With this analysis, the most optimum floor framing system can thus be applied for
design of tall buildings with slabs supported by largely space columns in the future.
Recommendations were given at theendof the report for further study of this project.