Study on performance of lightweight concrete bricks with a ratio of sand and cement composition

Cellular Lightweight Concrete (CLC) brick is a material composition for wall building made of Portland cement, water, and fine aggregate blended with a foaming agent. The weight of the brick is light due to the air cavities formed in the CLC brick. The number composition of sand and cement in the CLC brick could improve the strength of the bricks. Thus, it is essential to find out the sand and cement consumption in order to improve the rate of brick strength. The study aims to improve the strength of the CLC bricks with the different composition of the material and to find out the index properties of the CLC bricks with the variable component of the materials. The study used an experimental work in the material laboratory with two variations of the material composition. The first variation is mixing concrete for the ratio of cement and sand of 1:2, while the second variation is mixing concrete for cement and sand ratio of 2:3. The wet density of the CLC brick is about 800-900kg/m³, and the average compressive strength test was conducted at ages 3, 7, 14, and 28 days for each test. Three identical specimens were prepared for each test. The study resulted in the 28-day strength of the CLC brick with a mass ratio of cement to sand 1:2 of 0.52 MPa, and the strength of the CLC brick with a mass ratio of cement to sand 2:3 was 0.68 MPa. The first variation was lower by 24.5% than the second variation in terms of strength. The higher cement consumption used into the mixed can make porosity of the specimen decrease, and then the strength of the specimen will improve.