TITLE:
Study of Attapulgite as an Additive in Reinforced Concrete by Substitution of Cement and Its Effects on the Durability Properties of Hardened Concrete
AUTHORS:
Malang Bodian, Dame Keinde, Ismaila Yade, Kinda Hannawi, Prince William Agbodjan, Modou Fall, Aveline Darquennes
KEYWORDS:
Attapulgite, Concrete, Mechanical Properties, Pozzolanic Reactivity, Rein-forced Concrete
JOURNAL NAME:
Open Journal of Civil Engineering,
Vol.12 No.3,
August
8,
2022
ABSTRACT: The valorization of
Senegalese attapulgite clay in concrete, as a solution against the
exhaustion of the cement deposits was studied. In that purpose, attapulgite
was first calcined at 800°C to make it reactive and added in concrete by
substitution of Portland cement (CEM I 52.5N) at contents of 0, 5 and 10% by
conserving a constant water/cement ratio value of 0.65. The effects of the
partial replacement of cement by attapulgite on the physicochemical and
mechanical properties of the concrete as well as on the steel-concrete bond
were examined. For this purpose, the water porosity, the intrinsic permeability
and the density of the clay-based concrete were evaluated. Compression, tensile
and pull-out tests were carried out to determine the impact of clay on the Young
modulus, the compressive and tensile strengths and the steel-concrete bond.
This study was completed by a characterization of the pozzolanic reactivity of
calcined attapulgite. All the results of these studies were compared with those of Portland cement as a reference. The
substitution of cement by attapulgite up to 10% in concrete has only a small
influence on its porosity and permeability and confers to the concrete gain in
compressive strength of 11%. However, it caused a loss of steel-concrete
bond of 10%.