The use of southern Algeria dune sand in cellular lightweight concrete manufacturing: effect of lime and aluminium content on porosity, compressive strength and thermal conductivity of elaborated materials
Résumé
The aim of this work is to promote the utilisation of southern Algeria dune sand for aerated concrete production without autoclaving process. This study has been undertaken to investigate the effect of hydrated lime and aluminium content on the porosity, especially the introduced porosity, compressive strength and thermal conductivity of cellular concretes elaborated from southern-Algeria dune sand, hydraulic binder (cement- hydrated lime) and aluminium powder as expansive agent. In this study, a series of 16 compositions of dune sand cellular concretes (DSCC) is manufactured with different percentages of cement, hydrated lime and aluminium powder. For each mix, a number of test specimens (40 x 40 x 160mm(3)) was prepared and stored in the laboratory atmosphere at T=20 +/- 2 degrees C and HR=70 +/- 5% until the age of test. Experimental results reveal that the introduction of hydrated lime as partial substitution of cement tended: (i) to increase the total porosity of matrix; (ii) to reduce the rate of introduced porosity generated by the expansive agent and (iii) to diminish thermal conductivity as well as compressive strength of elaborated materials. It is shown that the expansion of DSCC paste decreases as a function of percentage of hydrated lime in the binder. Finally, southern Algeria dune sand can be utilised in producing lightweight cellular concrete. However, the use of cement as binder in manufacturing process is more recommended than the mix of cement and hydrated lime.