Compressive strength of cemented sand

Cemented sand is made from a mixture of sand, cement and water. Also known as Sandcrete, this material is widely used as a principal load-bearing and non-load bearing material in African countries due to its affordability, simple constructability and adaptability in tropical countries. The compressive strength of cemented sand is a significant property to consider, especially when used for the construction of residential buildings and communal areas. In this paper, the four main factors affecting the compressive strength of cemented sand will be investigated: water-cement ratio of 0.5, 0.6, 0.7; sand-cement ratio of 4.0, 5.0, 6.0; curing age at 3, 7 and 28 days; strain rate of 0.5mm/min, 1.0mm/min, and 2.0 mm/min. The other factors such as dry density, sample dimensions (height and diameter), curing conditions were kept constant. A total of 51 cemented sand samples were prepared for the experiment according to the specific mix proportions. After air curing at 95% humidity and 26⁰C (+/-3⁰C), unconfined compressive strength test was performed on the individual specimens. Stress-strain graphs were plotted from each compression test. It was found that an optimum water-cement ratio of 0.6 yielded the highest compressive strength at all ages. Cemented sand with a cement-sand ratio of 5.0 gave the highest compressive strength among the other ratios. Compressive strength was observed to increase with increasing curing age. Similarly, compressive strength of cemented sand showed a positive relationship with strain rate during unconfined compression test.Bachelor of Engineering (Civil