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Concrete Mix Design
Published in M. Rashad Islam, Civil Engineering Materials, 2020
Ready mixed (or ready-mix) concrete refers to concrete that is produced according to the specification of the contractor in a central plant (Figure 4.11) and delivered to the job site in a timely manner, using a large truck (Figure 4.12). Ready-mix concrete is better in quality compared to the conventional concrete, as the plant uses skilled laborers, advanced equipment, and consistent methods. There is a more well-defined process in a plant compared to a job site, and thus, the ready-mix concrete is more appreciated by the contractors. The ready-mix plant also uses more mechanical devices instead of manual labor. Thus, it has a smaller amount of human error in its operations. Better mixing practices reduce the consumption of cement and produce less dust, as ready-mix concrete uses a bulk concrete instead of bags of cement.
Durability and construction
Published in Mark Alexander, Arnon Bentur, Sidney Mindess, Durability of Concrete, 2017
Mark Alexander, Arnon Bentur, Sidney Mindess
Truck mixers are usually of the reversing drum type. Ready-mix concrete plants may have integral concrete mixers in their plant, or they may rely on the truck to effect the mixing. Further agitation of the mix may occur en route to the job site. In this case, adequate time must be allowed for the concrete to be thoroughly mixed before discharge. The efficiency of truck mixers is dependent upon cleanliness of blades, revolutions per minute, and whether the blades are designed for mixing or agitation.
Laboratory evaluation of an ecological pavement construction material: sand concrete reinforced with polypropylene fibres
Published in European Journal of Environmental and Civil Engineering, 2019
Riadh Ben Othman, Saloua El Euch Khay, Amara Loulizi, Jamel Neji
In the research described in this paper, two different sands, considered as material waste in the country, were reused in the formulation of a type of concrete: sand concrete reinforced with polypropylene fibres. This material is intended to be used in the construction of non-doweled jointed plain concrete pavements for secondary roads. The material is proportioned and mixed in conventional ready-mix concrete plants, transported to the site using regular trucks and finally placed by means of roller compactors.