Profiled steel sheeting. depths ranging from 45 mm to over 200 mm. yield strengths ranging from 235 N/mm2 to at least 460 N/mm2. 0.8 mm and 1.5 mm thick. The various shapes provide Interlock between steel and concrete.
Stress is the measure of an external force acting over the cross sectional area of an object. Stress has units of force per area: N/m 2 (SI) or lb/in 2 (US). The SI units are commonly referred to as Pascals, abbreviated Pa.Since the 1 Pa is inconveniently small compared to the stresses most structures experience, we'll often encounter 10 3 Pa = 1 kPa (kilo Pascal), 10 6 Pa = a MPa (mega Pascal. Plane cross sections continue to be plane after bending. Tensile strength of concrete is neglected because: Concrete's tensile strength is about 1/10 of its compressive strength. Cracked concrete is assumed to be not effective Before cracking, the entire cross section is effective in resisting the external moments.
decking may also be used to stabilise the beams against lateral torsional buckling during construction. stabilize the building as a whole by acting as a diaphragm to transfer wind loads to the walls and columns. temporary construction load usually governs the choice of decking profileComposite Columns. protection from fire. It is assumed to Resist a small axial load. to reduce the effective slenderness of the steel member, which increases its resistance to axial load.The bending stiffness of steel columns of H-or I-section is much greater in the plane of the web (‘major-axis bending’) than in a plane parallel to the flanges (‘minor-axis bending’). The ductility performance of circular type of columns is significantly better than rectangular types.
There is no requirement to provide additional reinforcing steel for composite concrete filled tubular sections. Corrosion protection is provided by concrete to steel sections in encased columnsWhile local buckling of the steel sections may be eliminated, the reduction in the compression resistance of the composite column due to overall buckling should definitely be allowed for.
The plastic compression resistance of a composite cross-section represents the maximum load that can be applied to a short composite column. Stress Distribution in an encased I Section Aspects for using composite structures:. Architectural. Economical. Functionality. Service and Flexibility.
AssemblyArchitectural. Longer spans. Thinner slabs. More slender column. More generous opportunities for designEconomical.
Reduction of height reduces the total of the building – saving area of cladding. Longer spans with the same height – column free rooms.
Additional storeys with the same total height of building. Quicker time of erection.
Finishing the top portion of the beam shall be a highly skilled job. The de -shuttering:It shall not be possible to first strike off the sides and then the beam bottom.The form work shall have to be removed in two halves after the concrete attains the strength. Comparing rectangular & square section.1) Beam width could match with the wall – fixing this geometric parameter the depth ofthe beam could be decided as per the design requirement.2) Beam strength varies in cubic magnitude of depth- and rectangularsection is efficient in comparison to square section. Moment of inertia is high for rectangular sections.