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

Cold recycling of asphalt mixes is becoming a usual pavement rehabilitation technique. The use of active fillers in conjunction with bituminous emulsion changes the properties of the mixes, mainly on the mastic characteristics. The use of active filler can make the mastic more brittle, but limited data are available on this aspect. In this study, emulsion-active filler mastics were prepared with two different mixing methods. Two different active fillers, ordinary Portland cement and fly ash, were used at four different contents with a single emulsion and an inert filler. Once cured, the mastics were tested with a dynamic shear rheometer (DSR) to get the viscoelastic properties at high temperature and with the double-edge-notched tension (DENT) test to look at the cracking potential at intermediate temperature. The results show that the order that the materials are incorporated during the mixing of the mastics does have a significant effect on the properties. Also, in terms of stiffness, the optimum amount of active filler is different for the cement than for the fly ash. For the cracking resistance, the results have shown that the addition of both active fillers does have an impact on the cracking resistance, but in the amount tested, no brittle fracture was observed. The results have shown that the type and quantity of active filler are important since it changes the fracture performance and the viscoelastic properties of bituminous mastic.

Marc-André Bérubé

Papers

Characterization of Cold Bituminous Mastics Prepared with Different Active Fillers at High and Intermediate Temperature