How do you calculate superplasticizer?
a) Free W/C ratio for the target strength of 48.3 N/mm2 as worked out is 0.39. b) Free water for 50 mm slump from Table 2 for 20 mm maximum size of aggregate. c) PPC = 137/0.39 = 351 kg/m3 This is lower than minimum requirement of 360 kg/m3. Then take 360 kg/m3.
How long does superplasticizer work in concrete?
about 100 min
Many modern superplasticizers can retain reasonable workability for a period of about 100 min, but care is still needed, particularly on projects where ready-mixed concrete delivery trucks require long journey times.
What is superplasticizer made of?
Traditional plasticizers are lignosulphonates as their sodium salt. Superplasticizers are synthetic polymers. Compounds used as superplasticizers include sulfonated naphthalene formaldehyde condensate, sulfonated melamine formaldehyde condensate, acetone formaldehyde condensate and polycarboxylate ethers.
How is superplasticizer made?
They are prepared by crosslinking of the sulfonated monomers using formaldehyde or by sulfonating the corresponding crosslinked polymer.
Does superplasticizer make concrete stronger?
The use of superplasticizers may produce high strength concrete (compressive strength up to 22,000 psi). Superplasticizers can also be utilized in producing flowing concrete used in a heavy reinforced structure with inaccessible areas.
What is used in superplasticizer?
Superplasticizers are synthetic polymers. Compounds used as superplasticizers include sulfonated naphthalene formaldehyde condensate, sulfonated melamine formaldehyde condensate, acetone formaldehyde condensate and polycarboxylate ethers.
Does superplasticizer increase strength of concrete?
Superplasticizers transform stiff, low-slump concrete into flowing, pourable, easily placed concrete. They can improve workability, speed finishing, increase strength, conserve cement and help reduce shrinkage and thermal cracking.
Which is best plasticizer?
Di(2-ethylhexyl) phthalate (DEHP), also known as dioctyl phthalate (DOP), was introduced in 1930 and has been the most widely used plasticizer since the 1930s.
What is concrete superplasticizer?
Superplasticizers (SPs), also known as high range water reducers, are additives used in making high strength concrete. Plasticizers are chemical compounds that enable the production of concrete with approximately 15% less water content.