Lowcement

Lowcement is a term used to describe cementitious materials and mixes designed with reduced Portland cement content compared with conventional formulations. It is applied to both structural concrete and refractory castables, and can involve different approaches depending on the application.

In structural concrete, low-cement concrete relies on replacing part of the Portland cement with supplementary cementitious materials such as fly ash, slag, or silica fume, together with chemical admixtures to maintain workability and strength. The aim is to lower embodied carbon, reduce heat of hydration and shrinkage, and often improve long-term durability. Achieving these benefits requires careful mix design, aggregate selection, curing strategies, and quality control to ensure adequate early strength, strength development, and resistance to environmental exposure.

In refractory engineering, low-cement castables use substantially reduced cementitious binder content compared with conventional castables. They often replace portions of Portland cement with alternative binders or bonding systems, which lowers hydration heat and can enhance high-temperature performance and abrasion resistance. The result is improved stability under thermal cycling and reduced risks of microcracking in service, albeit with demanding handling, placement, and curing requirements.

Benefits of lowcement mixtures include reduced environmental impact, potential cost savings, improved thermal performance, and enhanced durability when properly designed. Challenges include potential decreases in early strength, increased sensitivity to mix proportioning and curing, and the need for specialized materials, testing, and quality control. Ongoing research focuses on optimizing durability, workability, and long-term performance across applications.