Effect of Particle Size of Date Palm Seed Ash (Dpsa) on Concrete Properties

The effect of particle size of date palm seed ash (DPSA) on concrete properties was investigated through the use of different fineness of date palm seed ash (600um, 300um, 150um and 75um) at 2.5% replacement of cement with date palm seed ash and tested for compressive strength at 7, 21, 28 and 56 days curing duration. The consistency and setting times of cement-DPSA paste was also researched to determine the amount of water required to prepare hydraulic cement paste for testing. The date palm seed ash used was obtained by controlled burning of date palm

seed in a kiln in two stages: Firstly, it was burnt for eight hours at a maximum temperature of  590oC, and was cooled afterwards for two days. Secondly, it was further burnt for three hours at a maximum

temperature of 630oC and was again cooled for three days. It was then sieved through 75um sieve and its oxide composition analysed using X-ray fluorescence (XRF) procedures. DoE method of mix design was used to produce concrete ingredients for grade 30N/mm2 giving a water-cement ratio of 0.53. The results of oxide composition of date palm seed ash show that DPSA has high silicon dioxide (45.50%), aluminum oxide (20.75%) and Iron oxide (7.25%), making it a good pozzolana. Results also show that the consistency and setting times of cement-DPSA paste decreased with increase in the fineness of date palm seed ash. Further findings show that concrete made using 75um fineness of date palm seed ash gave the highest compressive strength of 33N/mm2 at 56 days curing duration.