Assessing Durability of Cement Kiln Dust Manufactured Aggregates
Abstract
Accelerated carbonation technology (ACT) is the addition of carbon dioxide and water and/or binder to a waste material to change an initially fine-grained waste material to an aggregate. For use in geotechnical applications, ACT aggregates must be durable. The objective of this thesis is to evaluate the durability (i.e. particle breakage) of a manufactured ACT aggregate made from cement kiln dust (CKD).
For an initial trial of ACT aggregate, several geotechnical tests related to the aggregate’s physical and chemical characteristics were performed. After refinement of the manufacturing process, it was shown that much stronger (3 MPa) ACT aggregate from CKD could be achieved. Hardin relative breakage (Br) was used to compare particle breakage under a variety of loading conditions (triaxial compression, triaxial shear and freeze-thaw) and particle size. It was shown that the 2.5mm to 1.25mm size had superior performance with respect to particle breakage under all the loading conditions.