Effects of water and sawdust additives on thermal effusivity, thermal conductivity and durability of cement-stabilized laterites

Abstract

The effects of water and sawdust additives on the thermal effusivity (e), thermal conductivity (λ), and durability of cement-stabilized laterites were investigated. The thermal effusivity (e) and conductivity(λ) have direct influ-ence on heat transfer and thermal insulation in buildings, and the parameters were determined by hot strip meth-od, which simultaneously estimated e and λ in less than 180 s using a thin rectangular electrical resistance dev-ice. The cement-stabilized laterites with sawdust additives exhibited higher thermal insulation than ordinary laterite bricks. Under dry conditions, λ = 0.648 W m^-1 K^-1, e = 975.4 J m^-2 K^-1 s^-½ for stabilized laterite with 4 % cement; λ = 0.574 W m^-1 K^-1, e = 893.4 J m^-2 K^-1 s^-½ for stabilized laterite with 4 % cement incorporating 2 % sawdust; and λ = 0.510 W m^-1 K^-1, e = 828.2 J m^-2 K^-1 s^-½ for stabilized laterite with 4 % cement incorporating 4 % sawdust additives. The samples exhibited mechanical strength satisfying construction criteria for building, i.e., water resistance to dry compression strength ranging from 2.857 to 4.286 MPa.