ANALYSIS AND DESIGN OF LARGE SPAN OFFICE BUILDING USING COLD FORMED STEEL SECTION

Abstract

This report involves analysis and design of an office building having a large multipurpose hall in which large span panels are designed as floor using universal beam (UB), universal column (UC) and HE cold formed section of steel with yield strength 310 Mpa. This study considered two buildings one is five storey office buildings having panels of dimension 9m x 5m, 7m x 5m and 5m x 4m. The next building is a Multi-Purpose Hall with dimensions 26m xl6m. In the Multi-Purpose Hall to avoid vision obstruction large floor panels are provided. In Multi-purpose Hall the column spacing has been varied in order to study its effect on the structural behaviour as well as to obtain an appropriate spacing of columns. For this purpose five different column spacing have been considered as 4.0, 4.5, 5.0, 5.5 and 6.0m. It has been found that at the spacing of 5.0 m although the section beam has increased however, the total steel intake has reduced due to the decrease in number of frames. In Multi-Purpose Hall, the column section has been designed once by tubular sections then by open section. It has been found that tubular section is economical and better choice for columns but the available range of tubular section is limited. In office building, once the whole building has been designed by using tubular sections and then by open sections for all elements except for the columns. It has been found that the available- range of tubular section is not sufficient to design bending element of intermediate span floors and the steel consumption is more in case of tubular section building. It has been concluded in the present study that bending elements cold-formed open sections like BE-sections are better choice than the tubular sections. The analysis and design has been carried out using STAAD.Pro confirming to the clauses of IS: 800 -2007 which is based on Limit state method. After study it is found that large span panels using cold formed steel section can be designed as floor. iii