Investigating the effect of sewage sludge in making bricks in the construction industry of Uganda.

Abstract

The Building Industry in Uganda today has got many construction materials being put to use. Many of these materials are very reliable due to their different potentials in terms of durability, strength say for concrete blocks, pavers, and the like; water tightness for clay products, fire resistance say for timber among others. Most of these materials are not readily available in their natural form. However, the same industry seems to have dropped readily available materials like sewage sludge deposits for the purpose of making bricks due to its inability to meet the required standards instead of finding remedies of how such materials can be improved to suit their purpose. The Principal objective of this research therefore, was to investigate the effect of sewage sludge as a component for brick making in the Construction Industry of Uganda. Chapter one of this thesis introduces a review of the literature on the main theoretical concepts of the existence of sewage sludge and its usage in making Composite Sewage Sludge bricks highlighting mainly on its compressive strength and water absorption. This chapter also identifies the existence of environmental gas pollutants attributed to animal dung especially in the pastoral areas of Uganda and the World at large emphasizing that most of it is not put to good use. Chapter two is a literature review showing ideas and views of other researchers about the issue as well as explaining some of the main terms that were considered in the research; followed by the methodical approaches (in Chapter three) that were used among which was determination of compressive strength and water absorption for seven batches of bricks prepared with the mixes: 0%, 5%, 10%, 15%, 20%, 25%, and 30% by weight of sewage sludge. Chapter four presents the results of methods used. Laboratory experiments conducted reveal that the sewage sample used consisted of Inorganic Clays of high plasticity; This thesis therefore concludes that it is possible to make good use of the sewage sludge wastes other than using it for manure mainly here in Uganda, and the study also poses queries for further research.