الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
The primary advantage of castellated beams is the improved strength due to the increased
depth of the section without any additional weight. In some instances, the depth is increased
as much as 50%. By increasing the depth of the beam, strong axis bending strength and
stiffness are improved as the strong axis moment of inertia, Ix, and section modulus, Sx, are
increased. Further, the castellation or holes also allow HVAC (heating, ventilation, and air
conditioning) ductwork, plumbing pipelines, and electrical conduits to pass through them
ultimately reducing the thickness of the floor assembly.
A finite element model of castellated steel simple and cantilever beams using SAP program
has been developed to investigate the natural frequency and the acceleration of the structure
due to human and rhythmic excitation. The results obtained from the finite element model
were compared with those obtained from AISC (2003) specifications equations for human
and rhythmic excitations. The ultimate distribution of the load that the castellated beams can
sustain is performed and the results are compared with the design equations of BS (5950)-1
(2000).
The Study revealed that the proposed finite element model is capable of predicting the natural
frequency and acceleration of castellated steel simple and cantilever beamsto an acceptable
accuracy.
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The verified FEM is used to investigate the optimum design and the ultimate load capacity
under applied static and vibration load for castellated simply supported and cantilever beams.
The minimum weight is considered the design objective and can be defined by the beam
rational factor. The rational factor is the ultimate distributed uniform load per beam weight.
The design constraints are implemented from the BS 5950 standards and AISC2003. Design
constraints include the Vibration limitations, overall beam flexural capacity, beam shear
capacity, overall beam buckling strength, web post flexure and buckling, vierendeel bending
of upper and lower tees and local buckling of compression flange.
The finite element analysis model is used to perform elastic buckling analysis and predict the
critical loads of steel castellated hot-rolled and built-up beams thcan satisfy the highestrational factor (minimum steel weight).