Evaluation of Qualities of Demolished Debris used as Substitutes of Aggregate in Construction Projects Management in Nigeria

Experts and stakeholders in the construction industry in Nigeria are skeptical regarding reuse of debris as substitutes at construction sites. This is largely due to scanty literature to demystify the inherent properties of debris. This study aims to evaluate the quality of demolished debris used as substitutes of aggregates in construction sites. The study adopted an experimental survey approach, in an attempt to accurately determine the values of the metrics upon which quality of debris and its justification for reuse and substitution as aggregate is based. Samples of demolished debris were collected, Furthermore, Statistical Package for Social Sciences (SPSS, version. 21) was used to compute the results obtained to aid in making inferences on the data. The simple mean and percentages were obtained where appropriate and Analysis of Variance (ANOVA) was used to evaluate the significance difference in the means of water absorption capacity, density and compressive strength between the fine aggregate and the coarse aggregates (denoted as J, A, K and S) as obtained from the four different construction companies in River’s state. A total of 60 cubes measuring 150mm x 150mm x 150mm were cast and cured for 7, 14, 21, and 28 days before being crushed. Due to the presence of porous cement paste on the rocks, recycled concrete waste aggregate absorb more water than typical fresh granite. A significant difference exists in level of water absorption and density between the natural concrete cubes and the recycled aggregates at , except for compressive strength of the concretes. The study therefore recommends that, a well-prepared sample could be used in the absence of natural concrete, but it is expected to compulsorily meet the specified requirements.