How Do Concrete Admixtures Save the Planet ?

• 30 March 2017
• Local News
• 2849 Views

Concrete is a mixture of cement, water, sand, coarse aggregates – and sometimes we add some chemicals called “admixtures”. The structural engineers define the right proportions of each elements which is the concrete mix design; usually they calculate it according to national guidelines or and standards. The appropriate mix proportions must be done carefully, the quality of raw materials is essential to obtain good results.

The potential qualities of a concrete will only be realised if it is correctly batched, mixed, placed and cured. The SIKA team is often contacted to improve the performance of concrete production. It is difficult to control each parameter, so the addition of admixtures helps the concrete producer to control the performance.

ADMIXTURE PROPERTIES

SIKA has been operating for 15 years in Cambodia. We are proud to have been producing our SIKA Admixtures in Phnom Penh since December 2015. We cooperate with and supply all the major concrete producers in Cambodia. When you look out of the window, a large part of the concrete used for buildings contains a little bit of concrete admixtures.

Admixtures make a great difference in fresh and hard concrete; the compression strength is higher thanks to the reduction of water in the mix, the concrete is easier to cast as the workability is improved, the duration before the concrete starts that hardened can be retarded (setting time extended) or shortened, and the capillaries in the concrete can be reduced to develop waterproofing properties. Admixtures are very technical and involve chemical reactions with the cement to control the formation of the crystals.

DID YOU KNOW ?

Cement in the concrete reacts with water and creates a crystal.This reaction is exothermic and releases a lot of heat. In some countries where the temperature is very high, they mix water with ice to reduce the temperature when the concrete is produced.

CONCRETE FACTS

The original use of concrete has been traced back to ancient Egypt, where it was used as an infill material for the pyramids.

Concrete is used twice as much in construction than all other building materials like reinforcement, timber, etc.

It is the most used material in the world in terms of volume.

The Roman-constructed Pantheon is still the world’s largest unreinforced concrete dome.

Thomas Edison held 49 concrete patents and experimented with precast concrete houses filled with concrete furniture, pianos and refrigerators.

Nowadays, construction companies are using scented form release agents to impart a pleasant smell in concrete, the most famous being bubble gum.

4 ADMIXTURES TYPES

Nowadays in Cambodia, concrete producers require long slump retention for flexible delivery and 100% strength development within 7days. The mostcommon 4 types of Ad-mixtures are:

1 Type D for ready mixed concrete or site plant that need retarder with low and mid strength requirement (<40Mpa)

PlastIment® R/96, Plastocrete® 907, Plastomix®250

2 Type G for ready mixed concrete or site plant that need retarder with high strength requirement (>40Mpa)

Sikament® 2000AT, SikaPlast®204 / 208 / D30, SikaViscocrete®151

3 Type F for precast concrete element

Sikament®NN , Sika Viscrete®3000-10 / 800 series

4 Waterproofing

Plastocrete N , SikaWT 200-P

SIKA BENEFITS

The Sika team is always involved in the selection and dosage of our admixtures in the concrete mix to ensure high quality concrete.

Also major cost-savings are possible thanks to admixtures because it helps increase the strength, so the concrete producers use less cement. This helps the environment: less cement = reduction of carbon dioxyde emissions. •

For more information please contact : sales@kh.sika.com or call 017 666 762 (Mr. Nila)