Production of a lightweight masonry block using alkaline activated natural pozzolana and natural fibers.

• Lightweight geopolymer blocks were produced for non-structural construction purposes. • Compressive strength in the block was 8.1 MPa and bulk density was reduced to 1269 kg/m3. • Hydrogen peroxide proved to be effective for reducing density in geopolymer matrices. • Fine aggregate positively affected strength and dimensional stability of geopolymer mortars. • Stabilization of geopolymer mortars with jute fibers was necessary to control cracking. • The fibers were also effective for controlling the non-brittle failure of the blocks. Lightweight geopolymers are alternative low-carbon footprint building materials with high potential to produce value added products for the construction industry such as low-density masonry units. This work focuses on presenting the development of a new lightweight masonry block using natural pozzolana-based geopolymer mortar, hydrogen peroxide as a foaming agent and jute fibers as reinforcement additive. The experimental plan allowed the optimization of the production process and the definition of the optimum quantities of hydrogen peroxide content, pozzolana: fine aggregate ratios and the appropriate amount of fibers to be incorporated. The experimental results demonstrate the feasibility of the production of new masonry units, which can achieve up to 8.1 MPa of compressive strength after 28 days of fabrication with reduced bulk densities of 1269 kg/m3. [ABSTRACT FROM AUTHOR]