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American Society for Testing and Materials

Ash-related issues during biomass combustion: Alkali-induced slagging, silicate melt-induced slagging (ash fusion), agglomeration, corrosion, ash utilization, and related countermeasures

Common to liquids, solids and substances in between the former two is that if a stress is applied to them, they will strain. Stress may be visualized by placing a small amount of fluid between two parallel plates. When one plate slides over the other, forces act on the fluid dependent upon the rate of the plate movement. This causes a shear stress on the liquid. Recall laminar flow of fluids through a tubular vessel. Strain is the response to the stress. If solids are elastic, they deform and return to their original shape. Since fluids are not elastic and, hence, viscous, their deformation is irreversible.

Introduction to rheology

Innovation in use and research on cementitious material

A review on ultra high performance concrete: Part II. Hydration, microstructure and properties

http://maquinamole.net/EcoSmartconcrete.com/docs/trbouzoubaalachemi01.pdf

Self-compacting concrete incorporating high volumes of class F fly ash: Preliminary results

Characteristics of mortar and concrete containing fine aggregate manufactured from recycled waste polyethylene terephthalate bottles

Performance of new viscosity modifying admixtures in enhancing the rheological properties of cement paste

Two reactive powder concretes (RPC) were produced on an industrial scale at the Universite de Sherbrooke and in a nearby precast plant. A 2.6 cubic meter mix was prepared in the central mixer of the precast plant. The ready mix RPC was sampled before and after the addition of steel fibers while the one produced at the precast plant was sampled only at the end of the mixing process. These RPCs were tested for compressive strength, modulus of elasticity, freezing and thawing cycling resistance, scaling resistance to deicing salts, and resistance to chloride ion penetration. The results show that a 200 MPa compressive strength could be achieved in both cases: after curing in hot water at 90 degrees C or in the low pressure steam chambers at the precast plant. Confinement of the RPC in a steel tube greatly increases its compressive strength and its ductility.

Mechanical properties and durability of two industrial reactive powder concretes

Metakaolin (MK) is a valuable admixture for concrete/cement applications that can enhance the performance of cementitious composites through high pozzolanic reactivity, much like silica fume (SF). While SF concrete is characterized by superior mechanical and durability performance, concrete containing MK achieves comparable properties at a lower price and with better workability. The objective of this study is to investigate the effect of cement replacement by MK on the durability of self-consolidating concrete (SCC); the effect of SF at similar levels of MK replacement has also been included for comparison. The durability performance of SCC was evaluated based on the results of drying shrinkage, freezing and thawing, salt scaling, and rapid chloride permeability tests. The results of these tests indicate that highly durable SCC mixtures can be produced using a high MK content with an optimum percentage of around 20%. The results also show that the durability of SCC, especially with high MK content, is higher than that of SCC containing SF.

Mohamed Lachemi

Papers

Self-compacting concrete incorporating high volumes of class F fly ash: Preliminary results

Characteristics of mortar and concrete containing fine aggregate manufactured from recycled waste polyethylene terephthalate bottles

Performance of new viscosity modifying admixtures in enhancing the rheological properties of cement paste

Mechanical properties and durability of two industrial reactive powder concretes

Effect of metakaolin and silica fume on the durability of self-consolidating concrete