Assessment of the Construction Resource Wastage Minimization Mechanisms on Concrete and Major Concrete Making Materials on the site: A Case Study in Jimma Town Building Projects.

Abstract

Most of the times, the actual percentage of waste generated is much higher than initially assumed, causing the additional cost of the project. Therefore, minimizing materials waste in the construction projects could yield great cost savings and profit increment. This research was attempted to assess the current situation of minimizing wastage of construction materials. The general objective of this study was to assess construction resource wastage minimization mechanisms on concrete and major concrete making material in Jimma town building project This study also identifies the main causes wastes and rank, identify the effects of the wastes and finally provided minimization practices of concrete and concrete making material wastes . The main tools for the collection of data included questionnaires, interviews, site visits and document collected is used to identify the various efforts that have been made in the past to evaluate and examine the causes and sources of construction materials waste. The data analyzed was calculated using the relative importance index (RII). The findings of this research indicated that the level of contribution of the waste sources to the generation of waste saw differences between the perceptions of the respondents (Contractors and consultants). The results from analysis ranked from the 1st to 5th position by contractors and consultants that the most significant factors causing construction waste on building construction projects are Design and documentation, Operation, Site management and practices, material and Site supervisor factors. The survey focused on the four most dominant materials in terms of influencing the project costs which are concrete and major concrete making material such as cement, sand, aggregate. The variables were then ranked in their order of importance based on the response of the consultant’s and contractors. Therefore, the this study conclude that in order to minimize wastage on building projects were practicing good construction management, proper storage and handling of material, encourage re- using of waste materials and uses of appropriate software package to minimize design changes and over ordering.