PARAMETRIC STUDY OF PRECAST REINFORCED ROOFING ELEMENTS USING CAD

Abstract

To fulfill the increasing demand of houses in the country within a reasonable time, prefabrication of structure. either in full or major components-is the only answer. Adoptiop of prefabrication leads to product with a better finish, quality and better utilization of material strength. In prefabrication, materials are used most efficiently and enormous time and money is saved. Prefabrication 'technology is better than cast-in-situ at places of adverse climatic and weather conditions like subzero temperature, inclement weather in rainy season and deserts. In cases, where the time period is the most critical factor, prefabrication technique is the only alternative. This dissertation work consists of the development of software package for Parametric Study of Precast Reinforced Concrete Roofing elements(Channel, Double T and Cored sections) using CAD conforming to IS: 456-1978 requirements. In this parametric study three conrete grades (i.e.M20, M25 and M30),two steel grades (i.e_ Fe250 and Fe415),for three spans (i.e.3000 mm, 6000 mm and 9000 mm)with five widths (i.e. 600 mm, 900 mm , 1200 mm, 1500 mm and 1800 mm) keeping four aspect ratios (depth/width ratio to 1.5, 2.0, 2.5 and 3.0) have been investigated. In Cored sections, inplace of aspect, ratio six cular core sizes have been investigated. The computer programs are written in FORTRAN and implemented on PC-XT and AT. The design program is quite general. It caters for load as per IS 875(part 2)-1987. However, the program is capable of designing for any other uniformly distributed load intensity which can be useful in the design of floor units. Drafting programs have been written in PLOT88 and 'C' (ur) language. These drafting programs takes their input from the design program. This program takes about 7 seconds in the design and 12 seconds in plotting of one section on PC286. The usages of this package- will not only relieve the designer from the repetitive and labourious design routine but increase the productivity with the optimal design from the available input parameters.