# Development of Lightweight Building Materials Using a Sustainable Chemistry Approach: The Multifunctional Effects of Garlic Husk Ash on Foam Concrete

## TL;DR

This study explores using garlic husk ash as a sustainable alternative to cement in foam concrete, improving durability and reducing environmental impact.

## Contribution

The novel use of garlic husk ash as a biomass-based pozzolanic material in foam concrete is introduced.

## Key findings

- GHA increased set times and improved long-term compressive strength at 90 days.
- Thermal conductivity decreased by 18%, enhancing insulation properties.
- Freeze–thaw resistance was exceptional, with GHA25 and GHA30 mixes retaining 87% strength after 50 cycles.

## Abstract

In this study, the
application of garlic husk ash (GHA) as a new
form of biomass-related pozzolanic material that could be used as
a partial replacement of cement in the production of foam concrete
was examined. GHAs added to cement were equal to 0–30 wt %.
The impact of GHA on various properties tested (i.e., mechanical strength,
durability, thermal conductivity, and microstructure) demonstrated
that GHA is a silica, low-calcium material. Adding GHA increased the
initial and final set times by up to 56 and 52%, respectively. As
water demand increased, workability declined. Despite the decrease
in early age compressive strength, later-age strength improved due
to pozzolanic activity. At 90 days, the GHA30 mix’s compressive
strength reached 12.80 MPa, slightly exceeding that of the control
mix. Insulation properties improved as thermal conductivity decreased
by 18% to 0.199 W/m·K. After 50 freeze–thaw cycles, the
GHA25 and GHA30 mixes maintained up to 87% of their compressive strength,
demonstrating exceptional freeze–thaw resistance. In high-GHA
specimens, SEM analysis confirmed the development of a denser microstructure
with increased C–S–H gel. The outcomes indicate that
GHA, as an abundant biomass byproduct, enhances the long-term durability
of lightweight concrete while minimizing the environmental footprint
associated with cement utilization. This research promotes the integration
of agricultural biomass residues into construction materials to improve
circular economy principles and foster the development of sustainable,
energy-efficient infrastructures.