Slump of concrete or mortar fluidity What is concrete ? How to check the slump of concrete and specifications for construction of concrete floors ?
Slump of concrete mix ?
In the quality control of concrete people are paying attention to the slump test of concrete mixed construction . This work is done in the field or in the laboratory to determine hardness , rigidity of concrete samples . Each concrete sample and each country has a different standard of personal slump .
Slump of concrete is simply a term to describe the hardness of concrete mixture how , rather than using generic descriptions such as wet or looseness . The height of the concrete mix is poured in after slump cone different from one sample to another. Samples with lower height is used mainly in construction, with high slump samples commonly used for road pavement construction .
For the slump of concrete mixtures based on our technological properties of concrete mixtures is determined by the composition and properties of materials used .
Cohesive ( self- filling water or mold ) of concrete mix is guaranteed by the cement paste . Cement paste content greater , more liquid consistency than our , fluidity concrete mix becomes. When taken in aggregate cement paste reduces the fluidity of the mix, concrete mix fluidity decreased as much as aggregate content and greater percentage of their area . When changes in the cost of cement concrete from 200 to 400 kg/m3voi water costs constant change fluidity concrete mixture as small and they can not practice until you get the computer working fixed .
Mixture fluidity changes only when the cost of the water change . This rule is called the “law of constant amount of water needed ” and allows the user to calculate simple dependence of the fluidity of the concrete mixture in water costs . Fluidity concrete mixture increases , the intensity was almost unchanged while increasing the cement content of the lake at a rate of N / X does not change or reduce aggregate .
If the receipt with the amount of cement needed to fill the voids between the aggregate , it received mixed concrete hardens , workability is not achieved . To become a working mixture should not fill the voids , but also translate in the aggregate layers separated by cement paste .
Depending on the nature of the ratio between aggregate and sand and rubble minimum amount of cement paste in concrete mixtures , ensuring their content is not stratified and compacted quality , ranging 170-200 , 1 in mixed hard and to 220-270 , 1 in mobile and mixed flow.
The properties of cement affects the fluidity of concrete mix : cement used has high standards of water reduces the fluidity of concrete mixtures ( with constant water costs ) . Concrete mixtures containing cement with additives puzzolanic port in silicon prism activity , particularly from sedimentary origin ( Trepl , diatomic ) , at the expense of water a slump cone is smaller than cement mixtures common port in the steering .
Fluidity concrete mixtures increased with increasing water content ( but if cost is a constant cement concrete strength will decrease ) . But each concrete mixture capable of holding a certain amount of water , the water content part of it separated from the concrete mixture , which does not allow . The water content change is a major factor to adjust the consistency of concrete mixtures . Stucco is a mixture of concrete material from the nearest mixing time is finished on time can pour concrete molds absolutely no intensity , can not be load bearing , liquid and amorphous , there are little bearing internal links , and can not be mechanical strength . The shape depends on molding equipment containing this mixture . Mixture is not structural concrete to concrete bearing stiffness ( modulus of elasticity ) . Actually, the author is only defined slump of concrete mixes ( or fluidity of the concrete mix , to measure flammable and casting of concrete mortar ) under a different name only.
Based on concrete slump of concrete is divided into 3 categories :
Hard Type SN < 1.3cm
Type plasticity SN < 8cm
Super plasticizer have SN = 10 – 22cm .
JSC management consultancy specializing in the design CMC building , construction of villas , luxury townhouses , high-rise building ( hotel ) … Customers visit the CMC website to learn more about CMC is providing services .
