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The thick bed mortar method has been around for hundreds, if not thousands of years. Historically, a sand/cement mixture was mixed with water to a fairly dry consistency and was spread on either a portland cement water paste (neat cement), or over cement powder spread on the surface which is then sprayed with water to create a slurry coat and spread over the surface. [1]
Self-consolidating concrete or self-compacting concrete (SCC) [1] is a concrete mix which has a low yield stress, high deformability, good segregation resistance (prevents separation of particles in the mix), and moderate viscosity (necessary to ensure uniform suspension of solid particles during transportation, placement (without external compaction), and thereafter until the concrete sets).
Concrete has a limited lifespan between batching / mixing and curing. This means that ready-mixed concrete should be placed within 30 to 45 minutes of the batching process to hold slump and mix design specifications in the US, [15] though in the UK, environmental and material factors, plus in-transit mixing, allow for up two hours to elapse. [16]
A concrete mixer (also cement mixer) is a device that homogeneously combines cement, aggregate (e.g. sand or gravel), and water to form concrete. A typical concrete mixer uses a revolving drum to mix the components.
High-strength concrete has a compressive strength greater than 40 MPa (6000 psi). In the UK, BS EN 206-1 [2] defines High strength concrete as concrete with a compressive strength class higher than C50/60. High-strength concrete is made by lowering the water-cement (W/C) ratio to 0.35 or lower.
Segregation in concrete is a case of particle segregation in concrete applications, in which particulate solids tend to segregate by virtue of differences in the size, density, shape and other properties of particles of which they are composed. when the workability of concrete is high under pouring conditions, or the amount of mortar is larger than the void volume of coarse aggregate, or the ...
The first modern theoretical models for soil consolidation were proposed in the 1920s by Terzaghi and Fillunger, according to two substantially different approaches. [1] The former was based on diffusion equations in eulerian notation, whereas the latter considered the local Newton’s law for both liquid and solid phases, in which main variables, such as partial pressure, porosity, local ...
The most common use for portland cement is in the production of concrete. [17] Concrete is a composite material consisting of aggregate (gravel and sand), cement, and water. As a construction material, concrete can be cast in almost any shape desired, and once hardened, can become a structural (load bearing) element.