Abstract
This study aims to evaluate the engineering properties of crushed sandstone sand from the Kawkaban Member (Tawilah Group) exposed in Zigan area, northeast Sana'a city. This was accomplished through various laboratory tests that evaluated grain size, water absorption, water content, specific gravity, unit weight, and deleterious materials content on Zigan sand (ZS) and compared with standard sand (SS). The results met ASTM and AASHTO requirements for fine aggregates except the gradation. The mortar mixes were prepared by grouping the component materials by weight, using a 1:2:4 mix ratio. The mortar specimens were immersed in water for 2, 7, 28, 56, 70, and 90 days. The SS mortar showed better results, with higher flexural strength (FS) and compressive strength (CS) values than those for ZS mortar across all curing periods. The CS values of SS mortar were 9.65% higher than the required limits, whereas ZS mortar fell 20.59% below the required CS values at the 28th day of curing. At 7 days of curing, the CS values for SS and ZS mortars were 70 and 80% of their respective values at 28 days. At 28 days of curing, the FS value of ZS mortar was 8.70% lower than that of SS mortar. With the designated water-to-cement (w/c) ratio and mix proportions, the ZS (Kawkaban Member) mortar was found suitable for structural applications where high strength is not required such as plastering and flooring.