Properties Assessment and Application of Regression analysis on the compressive strength of Hollow Sandcrete Blocks

The study focuses on the properties assessment and application of regression analysis on the compressive strength of hollow sandcrete blocks. A total of ten (10) block producers were visited and fine aggregates used in the production of sandcrete block collected, a total number of 10 blocks per producer was collected with a curing period of 7 days and transported to the laboratory of civil and environmental engineering, Air force institute of technology Kaduna, where it was further cured for an additional period of 7 days making it a total curing period of 14 days. The test carried out on the aggregates and the sandcrete blocks includes: sieve analysis, dimension and compressive strength test. The mix composition of each of the block producer was also determined. Modelling using Minitab software was used to carryout multiple regression analysis to develop a compressive strength model in terms of constituent materials for 14 days curing age of hollow sandcrete blocks. The test result obtained from the sieve analysis of sand from the various block producers revealed that the sand used by the block producers do not comply with the specified standard of grading of aggregates, the mix proportion and dimension of the sandcrete blocks used by the selected block producers does not comply with the required ratio and dimension, the average compressive strength of the blocks ranged from 0.24 N/mm2 to 0.35 N/mm2. The model generated for 14 days compressive strength gave coefficient of regression (R2) of 0.901 for the hollow sandcrete block, showing good correlation.