Assessment of Quality of Sand from Rivers Imo and Otamiri, Imo State for Construction Purposes

Abstract

This research presents assessment of quality of sand from Imo and Otamiri rivers, located in Imo State, southeast Nigeria for construction purposes. Tests carried out include sieve analysis, bulk density, specific gravity, organic content and California bearing test. The results classified the sand from both rivers as medium poorly graded, low compressibility, good drainage quality. The tests also revealed that the sand belong to Zone 2 of the grading curve of particle size distribution. The study further showed that sand from the two rivers have low California Bearing Ratio (CBR) values, which ranged between 0.15% and 0.22%. The pH value of sand from Otamiri river is 7 (Neutral), while sand from Imo River is slightly acidic with a pH value of 6.5. However the level of acidity does not pose a threat to any construction material. The Specific Gravity of Otamiri river sand averaged 2.57, which falls within the acceptable range of 2.50 and 3.00 for aggregates for construction purposes. The specific gravity of Imo river is 2.36, which is slightly below the given range. The research further revealed that sand from Imo river shows slight present of impurities which may be deleterious to chemical reaction of cement or bitumen. However, Otamiri river sand on the other hand, have little or no impurities. Sand from Imo River is slightly acidic and therefore not recommended for construction where steel materials are recommended or preferred, as this may aggravate corrosion and rust. Notwithstanding, with proper sorting, sand from both rivers are suitable for construction purposes.