International Journal of Scientific Research and Engineering Development

Lightweight foamed concrete (LFC) offers significant structural and thermal benefits in modern construction; however, foam instability during mixing and early curing results in non-uniform pore distribution and reduced mechanical performance. This study systematically evaluates the influence of Carboxymethyl Cellulose (CMC) as a foam stabilizer at dosages of 0.05%, 0.08%, and 0.10% by cement weight, combined with Alpha-Olefin Sulfonate (AOS) foaming agent at 0.5%, on workability, compressive strength, and split tensile strength of LFC across three binder-to-sand ratios (1:1, 1:2, 1:3). Forty-eight specimens were cast and water-cured for 7, 14, and 28 days. Foam stability was monitored by volume and mass retention over 25 minutes. Fresh concrete workability was assessed by the flow table test. Compressive strength was measured on 150 mm cube specimens (IS 15658:2006) and split tensile strength on 150 mm × 300 mm cylinders (IS 5816:1999). AOS and CMC (0.10%) foam retained its volume of 100%, while unsterilized AOS foam lost 17% of its volume over 25 minutes. The best combination (1:1, AOS 0.5%, CMC 0.10%) yielded a 28-day compressive strength of 4.67 MPa and split tensile strength of 0.47 MPa, which is a 32.7% and 34.3% increase over the unsterilized reference. Mean flow values were between 130 and 180 mm for various mix ratios. CMC effectively stabilizes AOS-generated foam and significantly improves the mechanical performance of lightweight foamed concrete, making it suitable for partition walls, precast panels, and non-load-bearing structural applications where reduced self-weight and thermal insulation are priorities.

Ramya S, Murugan M, Mohamed Ali E A,"Effect of Carboxymethyl Cellulose as Foam Stabilizer on Mechanical Performance of Lightweight Foamed Concrete with AOS Foaming Agent" International Journal of Scientific Research and Engineering Development, V9(3): Page(2312-2318) May-June 2026. ISSN: 2581-7175. www.ijsred.com. Published by Scientific and Academic Research Publishing.