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The preferred supplier of quality concrete, aggregate and
related building materials for Skagit and Snohomish Counties.

Our Admixtures Vendors

If you would like more information on our admixtures products please call us at 360-435-5791 or click on one of the following vendor links:

Lehigh Northwest Cement
http://www.lehighnw.com/

Euclid Chemical Company
http://www.euclidchemical.com/

Ash Grove Cement Company
http://www.ashgrove.com/

 

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Concrete Admixtures

Concrete admixtures reduce the cost of construction, modify properties of hardened concrete, ensure quality of concrete during mixing, transporting, placing, and curing, and overcome certain emergencies during concrete operations.

Chemical admixtures are used to improve the quality of concrete during mixing, transporting, placement and curing. They fall into the following six categories:

  1. Water reducers
  2. Set accelerators
  3. Air entrainers
  4. Set retarders
  5. Superplasticizers
  6. Specialty admixtures: corrosion inhibitors, shrinkage control, alkali-silica reactivity inhibitors, and coloring

Water Reducers

Water-Reducers are chemicals used to lower the water content and increase strength or to obtain a higher slump using the same water content for pumping the concrete or when you are dealing with hot weather.

A water reducer is recommended for use in:

Accelerators

An accelerator are chemicals that reduce the initial set time of concrete and are recommended in cold weather.

An admixture is recommended for use in concrete applications where accelerated time of setting and increased early strengths are desired.

Advantages: 

A accelerator provides the following advantages:

Hydration Stabilizers

The set-retarding characteristics of a Stabilizer aid in the production of concrete with the following special qualities:

A Stabilizer is recommended for use in all types of concrete where moderate to extended retardation of set time and improved performance are desired.

This admixture improves pumped concrete, shotcrete (wet mix) and conventionally-placed concretes.  It improves plain, reinforced, precast, prestressed, lightweight and normal weight concrete.

*** Primary Applications for use of a Stabilizer

  1. Stabilization of concrete washwater
  2. Stabilization of returned plastic concrete
  3. Stabilization of freshly batched concrete for long hauls

Stabilizers will not initiate or promote corrosion of reinforcing steel in concrete.

Air Entrainment

Concrete durability research has established that the best protection for concrete from the adverse effects of freeze/thaw cycles and deicing salts results from: proper air content in the hardened concrete; a suitable air-void system in terms of bubble size and spacing; and adequate concrete strength, assuming the use of sound aggregates and proper mixing, placing, handling and curing techniques.

When unusually low or high amounts of an air-entraining admixture are required to achieve normal ranges of air content or if the required amount of air-entraining admixture necessary to achieve required levels of air content is observed to change significantly under given conditions, the reason should be investigated.  In such cases, it is especially important to determine: (a) that a proper amount of air is contained in the fresh concrete at the point of placement; and (b) that a suitable air-void system (spacing factor) is being obtained in the hardened concrete.