Supplementary cementitious materials

Scanning electron microscopy and mercury intrusion porosimetry are used in parallel to identify the structure of a medium sensitivity Champlain clay. The clay structure is observed firstly on intac...

Study of the structure of a sensitive Champlain clay and of its evolution during consolidation

This paper examines the relationship between the microstructure and engineering properties of cement-treated marine clay. The microstructure was investigated using x-ray diffraction, scanning electron microscopy, pH measurement, mercury intrusion porosimetry, and laser diffractometric measurement of the particle size distribution. The engineering properties that were measured include the water content, void ratio, Atterberg limit, permeability, and unconfined compressive strength. The results indicate that the multitude of changes in the properties and behavior of cement-treated marine clay can be explained by interaction of four underlying microstructural mechanisms. These mechanisms are the production of hydrated lime by the hydration reaction which causes flocculation of the illite clay particles, preferential attack of the calcium ions on kaolinite rather than on illite in the pozzolanic reaction, surface deposition and shallow infilling by cementitious products on clay clusters, as well as the presence of water trapped within the clay clusters.

Physicochemical and engineering behavior of cement treated clays

http://cec.sut.ac.th/download/published/CBM-micro.pdf

Analysis of strength development in cement-stabilized silty clay from microstructural considerations

Utilization and efficiency of ground granulated blast furnace slag on concrete properties – A review

Mineralogical and microtextural changes associated with lime stabilization of marine clays from eastern Canada

Long-term effectiveness of supplementary cementing materials against alkali–silica reaction

The effectiveness of supplementary cementing materials in suppressing expansion due to ASR: Another look at the reaction mechanisms part 1: Concrete expansion and portlandite depletion

Evaluation of the validity of the pore solution expression method from hardened cement pastes and mortars

Alkali-aggregate reaction (AAR) is only one of the many factors that might be fully or partly responsible for the deterioration and premature loss in serviceability of concrete infrastructure. Two types of AAR reaction are currently recognized depending on the nature of the reactive mineral; alkali-silica reaction (ASR) involves various types of reactive silica (SiO2) minerals and alkali-carbonate reaction (ACR) involves certain types of dolomitic rocks (CaMg(CO3)2). Both types of reaction can result in expansion and cracking of concrete elements, leading to a reduction in the service life of concrete structures. This document describes an approach for the diagnosis and prognosis of alkali-aggregate reactivity in transportation structures. A preliminary investigation program is first proposed to allow for the early detection of ASR, followed by an assessment (diagnosis) of ASR completed by a sampling program and petrographic examination of a limited number of cores collected from selected structural members. In the case of structures showing evidence of ASR that justifies further investigations, this report also provides an integrated approach involving the quantification of the contribution of critical parameters with regards to ASR.

Marc-André Bérubé

Papers

Mineralogical and microtextural changes associated with lime stabilization of marine clays from eastern Canada

Long-term effectiveness of supplementary cementing materials against alkali–silica reaction

The effectiveness of supplementary cementing materials in suppressing expansion due to ASR: Another look at the reaction mechanisms part 1: Concrete expansion and portlandite depletion

Evaluation of the validity of the pore solution expression method from hardened cement pastes and mortars

Report on the Diagnosis, Prognosis, and Mitigation of Alkali-Silica Reaction (ASR) in Transportation Structures