Slag-lime binder

The materials for the base and sub-base course are unbound aggregate mixtures or hydraulically bound aggregate mixtures. The aggregates may be crushed granular materials, manufactured materials from rock deposits or industrial by-products (slags) or recycled materials. The hydraulic binders, in the case of bound materials, are cement, fly ash, slag, lime, a mixture of some of them or factory-blended hydraulic binders for road use. 

The binders are silica, lime, slag, or cement. The balls are somewhat dried, if necessary, and then cured in steam autoclaves. During the hydrothermal treatment lime and silica react to form hydrosilicate gels, which act as binders. 

Solidification/stabilization Refers to reducing the mobility of a contaminant in soils, other solids, or even liquid wastes by mixing them with Portland cement, lime, cement kiln dust, clays, slags, polymers, water treatment sludges, iron-rich gypsum, fly ash, and/or other binders. The process decreases the mobility of contaminants through physical encapsulation (solidification) and chemical bonding between the contaminants and the binders (stabilization). 

Solidification/stabilization processes play a more important role since, in the near future, only inert or stabilized wastes should be landfilled. Solidification/stabilization process means binding the hazardous material in the hydraulic binders for safe landfilling or use in civil engineering purposes. Various types of cement, inorganic binders and pozzolanas (e.g., coal burning fly ash, lime, blast-furnace slag and similar materials) are mostly used as the... 

Soil stabilisation is the process of improving the engineering properties of the soil to increase its bearing capacity and hence its strength. The process involves the use of hydraulic binders such as cement, lime, lime/cement mix and pulverised fuel ash often with lime or blast furnace slag by itself or mixed with cement. This is known as additive stabilisation or chemical stabilisation. In all cases, the hydraulic additives intermingle with the soil material at the project site. Additive stabilisation rarely takes place away from the project site. 

The hydraulic binders or constituents such as cement, fly ash, slags and lime should comply with CEN EN 197-1 (2011), CEN EN 14227-4 (2013), CEN EN 14227-2 (2013) and CEN EN 14227-11 (2006), respectively. Additionally, any other hydraulic road binder, that is, factory-blended hydraulic binder for road use, may also be used, provided it complies to CEN EN 12447-5. 

The soil requirements when treated by hydraulic binder are specified in the appropriate specification depending on the binder used CEN EN 14227-10 (2006) for soil treated by cement, CEN EN 14227-11 (2006) for soil treated by lime, CEN EN 14227-12 (2006) for soil treated by slag, CEN EN 14227-14 (2006) for soil treated by fly ash and CEN EN 14227-13 (2006) for soil treated by hydraulic road binder. 

However, apart from the cement binder (ASTM C 150 2012 or AASHTO M 85 2012), the hydraulic binders may be blended hydraulic cement (ASTM C 595 2013 or AASHTO M 240 2013), coal fly ash and raw or calcined natural pozzolan (ASTM C 618 2012 or AASHTO M 295 2011), ground granulated blast-furnace slag (ASTM C 989 2013 or AASHTO M 302 2013), silica fume (AASHTO M 307 2013) and lime (ASTM C 977 2010 or AASHTO M 216 2013). 

The effect of lime- (CaO) rich phases penetrating the brick is to render the muUite binder in the refractory as a nonequiUbrium phase, i.e., the binder is dissolved into the penetrating slag phases and corrosion products. In 70% AI2O3 brick, the mullite is stable until the local composition reaches 20% CaO, while in 90% AI2O3 brick, the mullite disappears when the local composition reaches 8% CaO. 

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