Your Concrete begins with sand and stone mixed with cement and water. The cement and water begin to bind to the sand and stone in a process called hydration. We add chemicals to introduce small bubbles into the concrete to reduce damage that can be caused by salt, freezing and thawing. Cement only requires a small amount of water to begin hydration. The more water added after this point the weaker the bond to the aggregates. Therefore we add chemicals to lessen the amount of water necessary for a workable mixture.
Our job is to bring you concrete with the proper portions of these components. However to insure strength and durability requires more work. Following these guide lines will ensure years of use of your concrete.
Planning your concrete job for correct drainage to minimize standing water on surface and according to your village building code is essential.
Planning ahead is crucial to control cracking. A firm base under the concrete, space for expansion and contraction as temperatures fluctuate and proper placement of control joints will help reduce visible cracks.
Proper depth of the concrete will also reduce cracking.
The addition of water will dilute the mixture and decrease strength and durability. Add as little water as possible to make concrete workable at the jobsite.
WARNING: Do not spray water over surface of unhardened concrete.
Finishing with water on the surface will weaken the surface and may cause problems later.
Over finishing can also weaken the surface by breaking the bonds of cement as it is trying to harden. Outdoor surfaces should have a rough finish to prevent slipping. This is usually done with a medium/fine bristle broom, however, broom-ing wet concrete can weaken the surface.
Your concrete must be cured to attain the strength and durability potential of the concrete. Curing maintains the concrete at satisfactory moisture and temperature conditions to allow hydration to continue. Curing should commence following placement and extend a minimum of 7 days.
Any one of the following methods can be used:
* Spray on curing compound (according ASTM C309).
* Polyethylene cover.
* Seven day continuous water cure.
* Saturated burlap with polyethylene cover.
Discoloration may occur as a result of curing. This is usually temporary. Care must be taken to avoid contaminates on surface during curing process.
Once your concrete is cured and given an opportunity to air dry (approximately 2 weeks to 1 month). Place a small piece of plastic on the concrete overnight if no water condenses under it, it is ready to be sealed. A protective sealer minimizes moisture and deicing salt penetration into the surface of the concrete. Concrete surfaces must be sealed when ambient temperatures are favorable and certainly before the onset of winter. Depending on the type of sealer, regular maintenance may be required. Discoloration may occur as a result of sealing.
Although concrete is one of the most durable construction products, it endures the harshest elements of our climate. Other wearing surfaces such as carpets and wood floors often have protective products applied (i.e. stain resistors and sealers) to extend their service life and durability while facilitating easier maintenance. To provide the same protection to your concrete, it is recommended that it be treated with a protective sealer. We recommend thin even coats with careful attention to cover the complete surface. By following the guidelines outlined in this brochure, your concrete will be durable and serviceable for many years to come.
The color of your concrete can vary depending on sunlight and shade, moisture in the sub-base, humidity, temperature, curing method, sealer, addition of water, addition of calcium chloride, and using differing strength concrete or different types of cement.
Concrete should not be poured
-in the rain
-on standing water
-When temperatures are 40°and dropping
-When temperatures are forecast to drop below freezing within the next 3 days
Unharded Concrete should be protected from
-direct sunlight on warm days
-snow & ice
Care and Maintenance
The following care and maintenance guidelines will add to the value of your investment:
1. Do not apply deicing chemicals for snow and ice removal during the first winter. And little as possible after the first year. To provide traction, sand is recommended.
2. Never apply deicers containing ammonium sulphate or ammonium nitrate. These products may be packaged and sold as deicers, but aggressively attack and deteriorate concrete surfaces.
3. For stain removal, do not use harsh acids. Use a product specifically designed for the stain in question and for use on concrete.
4. Keep concrete clean of snow and ice at all times. Snow and ice may melt ,penetrate and refreeze causing damage the concrete surface.
Information on sealers- http://www.concretenetwork.com/sealer-buyers-guide/