PRECAST FERROCEMENT ELEMENTS FOR LOW COST HOUSING

Abstract

Use of ferrocement for a low cost industrialized housing construction is quite appropriate especially for a developing country like India, due to its economy, speedy construction, local availability of the materials in abundance, and most important of all, the use of unskilled labour. Though,a lot of research work has taken place for the develop-ment of suitable flooring, roofing and walling units in fer-rocement, due to the poor dissemination of this information, the practicing engineers and architects are totally unaware of these developments and, therefore, hesitating to take up this material for housing. In spite of this, due to the con- , certed research efforts made in many parts of the world, the application of ferrocement in various fields, especially in housing has been found to be a great success and is being looked as most potential material to fulfil the aspirations of the weaker sections of the society. 1 The present study is, aimed at the following- i) Standardisation and design of prefabricated ferroce-ment units for a multistoried building to promote the concept of industrialised housing for low cost housing. Towards this the concept of multipurpose units is pro-posed for economic viability. ii) In case of industrialized housing constructions, achieving monolithicity of joints always poses a prob-lem. In view of this, the relative performance of dif-ferent types of jointing between the ferrocement elements need to be investigated. An experimental pro-gramme has been undertaken to investigate the efficiency of different types of jointing. iii) Experimental verification of the behaviour .of a two storeyed model building assembled from the precast mul-tipurpose units under field loading conditions has also been undertaken. iv) A cost effectiveness study between ferrocement cons-truction and the other conventional type of construc-tion has been carried out to establish the superiority of the former. The standardised multipurpose units have been designed for the design forces obtained by the finite, element analysis of a chosen four storeyed hostel building. For this purpose the finite element formulation chosen is exact and economical too and an existing computer program.'MAPWBI have been used for the analysis. The scope of analysis is limited to linear analysis only where-in the ferrocement composite has been treated as a homogeneous and isotropic material with equiva-lent properties. Efficiency of four different types of joints such as monolithic, welded skeletal steel with overlap of wire mesh alone and bolted joints has been studied by testing two joint specimens of each category. Behaviour of an experimental model building 'has been studied by errecting a two storeyed model building by using a precast multipurpose unit of double T section for the walling • iv and roofing units. Bolted connections have been preferred at floor levels. The building has been tested under field load conditions and its behaviour reported. Lastly, a cost effectiveness study has been carried out between the building constructed by using precast ferro- • cement elements and conventional constructions, viz. masonry construction and R C framed building with infilled masonry panels. The study reveals the relative economy of the ferro-cement construction.