Summer is alomost here...Hot Weather Concrete Tips

Higher concrete temperatures produced by warmer weather can cause significant problems when placing, finishing and curing fresh concrete. Special precautions need to be taken during this time.

Hot weather produces a condition where there is a rapid loss of moisture from the concrete surface and accelerated concrete set times. Another problem directly associated with hot weather and warmer concrete temperatures is an increase in water demand which will raise the water/cement ratio and reduce concrete strength.

Accelerated slump loss and a loss of entrained air are also a result of higher concrete temperatures. Here are some general guidelines that should be followed when placing concrete during the warmer times of the year.

1. Plan and schedule concrete placement well in advance to avoid delays in delivery, placing, finishing and curing. Trucks should be able to begin discharging immediately upon arriving at the project site. There should be adequate personnel available to place and finish the concrete. When possible, deliveries should be scheduled to avoid the hottest part of the day.

2. Limit the addition of water at the job site. Add water to concrete only upon arrival at the job site to adjust the slump. Never add water to concrete that is more than 1 ½ hours old.

3. Thoroughly moisten the subgrade, forms, and reinforcing steel prior to concrete placement. Avoid standing water.

4. Begin curing the concrete surface immediately upon the completion of the finishing operation.

5. Protect field test cylinders by shading and prevent evaporation of moisture from test cylinder surfaces by using a non-absorbent cover. Maintain test specimens between 60 and 80 degrees F. during the first 24 hours after molding.

These steps will insure that you will have greater success with your concrete. If you have any questions, please call any Boudreau" Readymix of Hemet concrete sales representative. They will be happy to assist you.