[01] Bozabe Renonet Karka, Department of Civil Engineering, National High School of Publics Works (NHSPW), University of N’Djamena, N’Djamena, Chad. [02] Bassa Bruno, Faculty of Exact and Applied Sciences (FEAS), University of N’Djamena, N’Djamena, Chad.

The study is an experimental approach to stabilize a soil mass of laterite. Preliminary identification parameters and physical characteristics of the soil collected on site are determined in the laboratory. Next, the “trial and error” method is used to perform different mixtures by varying the proportions of fine particles and CPJ 32.5 cement. With these mixtures and with the help of a manual press, the freestanding and heavy blocks are produced. After cures of 7, 14 and 28 days, the results of the tests show that the resistance to compression (RC) of the blocks in the dry state gradually increases depending on the cement dosage and the duration of cure. At 10% cement and around 30% fine particles, the value of the RC of 7.9 MPa after 28 days is higher than the recommended values of 4.0 MPa for load-bearing walls by the International Centre for Earth Architecture (CRAterre). Moreover, a 24-hour stay of the dry blocks in the water causes the RC to fall from 22% to 28% depending on the cement dosage. However, the absorption coefficient of 2.48 g/cm².s^1/2 of blocks with 10% cement is less than 20 g/cm².s^1/2, limit value below which the NFP554 standard qualifies the low capillarity blocks. However, this loss of RC has no impact because its value at the fall remains higher than the recommended normative values. Finally, this stabilization approach makes it possible to obtain resistant blocks with a rational cement dosage, aesthetic aspect, low capillarity and cost.

Absorption Coefficient, Compressive Strength, CPJ 32.5 Cement, Carrier Wall, Fine Particle, Laterite

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