الفهرس | Only 14 pages are availabe for public view |
Abstract Precast reinforced concrete elements are widely used for construction of buildings in many countries. The benefits of the precast method, as compared to the cast in-situ method, lie primarily in the easier quality and production control of the structural components and in the onsite construction speed. There is a reduction in the amount of in-situ concrete required on-site and reduced delays caused by bad weather and seasonal conditions. This has a great influence on the cost and projects schedules. In the latest years, a large number of precast prestressed concrete structures have been built all over many countries. Prestressed concrete is structural concrete in which internal stresses have been introduced to reduce potential tensile stresses in the concrete resulting from loads. It is used in a wide range of building and civil structures where its improved performance can allow for longer spans, reduced structural thicknesses, and material savings compared with simple reinforced concrete. There are two kinds for this type of concrete structures; pretension concrete and posttension concrete. Typical applications include high-rise buildings, residential and industrial ceilings, stadiums, parking garages, bridges, conference halls…. etc. The aim of this study is to get a better understanding of the behavior and response of the precast prestressed concrete floors as well as to compare the different advanced techniques with the traditional construction method of concrete structures. Two cases of studies for real buildings were designed by three different methods using ADAPT Builder and CONCISE Beam programs, which depend on finite element method. The first case of study was designing a part of factory in at Sadat-city of dimensions 24x40 m2 divided into panels 8x8 m2 and the second case of study was to design wedding hall of area 18x30 m2 without any interior columns. Different techniques for constructing floors such as precast prestressed, post tensioned and traditional reinforced were used. The results of the alternative selected solutions were analyzed and compared in terms of flexure, deflection, stresses and the overall cost. The finite element results showed that using precast prestressed reinforced concrete techniques give best results compared to the other techniques. |