Light weight concrete is prepared by:

🧹 Methods of Making Lightweight Concrete

Lightweight concrete (density < 1800 kg/m³) can be produced by any of three methods, and the question correctly lists all of them:

A — Lightweight aggregates (expanded clay, pumice, blast-furnace slag) reduce density while the mix retains a normal mortar matrix.

B — No-fines concrete (omitting sand) leaves large voids between the coarse aggregate particles.

C — Aerated concrete uses foam-forming agents or gas-forming chemicals (e.g., aluminium powder) to create a cellular structure throughout the paste.

Key takeaway

Three routes to lightweight concrete: (1) light aggregates, (2) no fines, (3) foam/gas. Each targets density reduction differently.