11-03-2010, 12:21 PM
Please send any project report on Design of Post Tensioned Slab
11-03-2010, 12:21 PM
Please send any project report on Design of Post Tensioned Slab
26-07-2012, 02:10 PM
DESIGN OF POST TENSION SLAB
DESIGN OF POST TENSION SLAB.docx (Size: 17.94 KB / Downloads: 176) ABSTRACT Post-tensioning is a method of reinforcing (strengthening) concrete or other materials with high-strength steel strands or bars, typically referred to as tendons. Post-tensioning applications include office and apartment buildings, parking structures, slabs-on-ground, bridges, sports stadiums, rock and soil anchors, and water-tanks. In many cases, post tensioning allows construction that would otherwise be impossible due to either site constraints or architectural requirements. we would like to carry our major project for the final year on these PT slabs, which are seeming to be a new trend in present generation.
20-08-2012, 04:24 PM
POST-TENSIONED SLABS POST-TENSIONED.pdf (Size: 3.68 MB / Downloads: 355) Introduction General Post-tensioned construction has for many years occupied a very important position, especially in the construction of bridges and storage tanks. The reason for this lies in its decisive technical and economical advantages. The most important advantages offered by post-tensioning may be briefly recalled here: - By comparison with reinforced concrete, a considerable saving in concrete and steel since, due to the working of the entire concrete cross-section more slender designs are possible. - Smaller deflections than with steel and reinforced concrete. - Good crack behaviour and therefore permanent protection of the steel against corrosion. - Almost unchanged serviceability even after considerable overload, since temporary cracks close again after the overload has disappeared. - High fatigue strength, since the amplitude of the stress changes in the prestressing steel under alternating loads are quite small. Historical review Although some post-tensioned slab structures had been constructed in Europe quite early on, the real development took place in the USA and Australia. The first posttensioned slabs were erected in the USA In 1955, already using unbonded posttensioning. In the succeeding years numerous post-tensioned slabs were designed and constructed in connection with the lift slab method. Post-tensionmg enabled the lifting weight to be reduced and the deflection and cracking performance to be improved. Attempts were made to improve knowledge In depth by theoretical studies and experiments on post-tensioned plates (see Chapter 2.2). Joint efforts by researchers, design engineers and prestressing firms resulted in corresponding standards and recommendations and assisted in promoting the widespread use of this form of construction in the USA and Australia. To date, in the USA alone, more than 50 million m2 of slabs have been post tensioned. Punching shear General Punching shear has a position of special importance in the design of flat slabs. Slabs, which are practically always under-reinforced against flexure, exhibit pronounced ductile bending failure. In beams, due to the usually present shear reinforcement, a ductile failure is usually assured in shear also. Since slabs, by contrast, are provided with punching shear reinforcement only in very exceptional cases,because such reinforcement is avoided if at all possible for practical reasons, punching shear is associated with a brittle failure of the concrete. This report cannot attempt to provide generally valid solutions for the punching problem. Instead, one possibile solution will be illustrated. In particular we shall discuss how the prestress can be taken into account in the existing design specifications, which have usually been developed for ordinarily reinforced flat slabs. |
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