Jobs
Construction Aggregate
Construction aggregate, or simply aggregate, is a broad category of coarse- to medium-grained particulate material used in construction. Traditionally, it includes natural materials such as sand, gravel, crushed stone. As with other types of aggregates, it is a component of composite materials, particularly concrete and asphalt. Aggregates are the most mined materials in the world,[1][2] being a significant part of 6 billion tons of concrete produced per year.[3] Aggregate serves as reinforcement to add strength to the resulting material. Due to the relatively high hydraulic conductivity as compared to most soil types, aggregates are widely used in drainage applications such as foundation and French drains, septic drain fields, retaining wall drains, and roadside edge drains. Aggregates are also used as base material under building foundations, roads, and railroads (aggregate base). It has predictable, uniform properties, preventing differential settling under the road or building. Aggregates are also used as a low-cost extender that binds with more expensive cement or asphalt to form concrete. Although most kinds of aggregate require a form of binding agent, there are types of self-binding aggregate which require no form of binding agent.[4] More recently, recycled concrete and geosynthetic materials have also been used as aggregates.
Thirsk is a market town and civil parish in North Yorkshire, England; it is known for its racecourse, quirky yarn bombing displays and depiction as local author James Herriot's fictional Darrowby.
Archeological finds indicate there was a settlement in Thirsk around 500–600 BC. The town's name is derived from the Old Norse word þresk meaning fen or lake.
Thirsk is mentioned twice in the 1086 Domesday Book as Tresche, in the Yarlestre wapentake, a village with ten households. At the time of the Norman invasion the manor was split between Orm and Thor, local Anglo-Saxon landowners. Afterwards, it was split between Hugh, son of Baldric and the Crown.
