Accepted Papers to Appear in Future Issues

Improving properties of modified clay with cement containing random chicken feather fibers

Abdelkader Zerrouk, Abdelkader Kadri, Abdelkader Bougara
Abstract
Over the past decades, the poultry meat processing industry’s growth has generated a huge amount of feather “waste”. This waste has given rise to a number of environmental concerns and had a low value-being when used in many industrial applications. Promoting the use of sustainable materials is now a pole of interest in engineering construction. Aiming to recover this waste in enhancing the properties of problematic soils, an experimental study is conducted using these materials. An earth material named Zebabdja clay is treated by the cement to improve its properties. The inclusion of waste byproducts such as chicken feather fibers would improve the characteristics of the soil with low load bearing capacity. The present work attempts to valorize this kind of natural fiber in the field of building and solve an environmental problem using local materials. The control parameters evaluated herein include cement content (6%, 8%, 10% et 12%) and chicken feather fibers contents (1%, 2% et 3%). The unconfined compressive and direct shear tests were measured at different curing times. The results found show that 10% is the needed amount of cement to be used in order to stabilize the clayey soil treated. An increase in chicken feather fibers up to 2% indicates an improvement of the mechanical performances of the clayey soil, which may constitute a very interesting engineering solution for the weak soil.
Accepted : 2022-05-30

Etude de la pouzzolanicité de deux argiles de Kindia (Guinée) en vue de leur utilisation dans la formulation de liant hydraulique

Mamadou Yaya BALDE, Chantale NJIOMOU DJANGANG, Ousmane Tougué BALDE, Philippe BLANCHART, Daniel NJOPWOUO
Abstract
This work presents, firstly, the results of pozzolanicity tests on two varieties of clay, codified respectively ABD and ARD, taken at Débélé. In a second step, the physical properties of the mortars obtained from these two varieties by substitution of cement at a rate of 20% are presented and discussed. The mass of portlandite (CH) fixed by the powders calcined at 600°C is 1107.43mg and 796.15mg respectively for ABDc and ARDc. The mechanical activity index, at 28 days of curing is 93.54% (ABDc) and 88.13% (ARDc) with values increasing with the age of the specimens. The mechanical behaviour of the mortars shows acceptable variations with apparent densities between 1.800 and 2.090 g/cm3. The mechanical resistance is lower than that of the control mortar for hybrids based on raw clays, but those of hybrids based on calcined clays are higher than that of the control mortar beyond the 28th. These results attest to the pozzolanic character of the Débélé clays and constitute a contribution to their valorisation in the formulation of hydraulic binders.
Accepted : 2022-06-12