PROFESSIONAL CONTRACTORS

Contractor Tips

• To have the best chance of getting concrete when you need it, order 24 to 48 hours in advance. (If you need a concrete pump please place reservations at least 3 days in advance. Names and numbers will be provided upon request).
• Confirm “will call” orders at least 1 hour in advance.
• Order as close to the amount needed as possible. (If you order 6 trucks, don’t order 3 and ask for a 3-load balance. This can destroy the dispatcher’s scheduling for the day, and lessen the chances of receiving the balance of your order on time).
• Give the dispatcher good directions, a street address, and which side of the road you are on, (north, south, east, west).
• If you need to change your order, please call dispatch at least 1 hour before your order is expected.
• Inform the dispatcher if your job is going to be a slow pour or a “time job”, this will help him in his scheduling for the day.
• Do not use excessive water to increase the slump or make a loose mix; this will weaken the concrete mix. (If a loose mix is required, please contact the quality control personnel or ask the dispatcher for a mix with a high slump).
• Get to know what slump is and how it affects your concrete and its strength. (Ask our quality control personnel for assistance).
• Have only one person on the jobsite giving directions and instruction to the driver.
• Be ready and willing to back the truck into and out of the jobsite; this might include stopping traffic on a busy street temporarily.
• Be aware of obstructions to the truck on the job site, such as wires, branches, soft soil and dry wells.
• We recommend 4000psi concrete be used for all exterior flat work.
• Be sure to allow your concrete to cure properly.
• Do not begin to finish your concrete until all the surface water has disappeared; the surface of the concrete should look dulled.
• Be careful working around the truck and the discharge chutes. (Never work or walk under the discharge chutes).
• The truck carries 3 extension chutes. (The truck cannot hold any additional chutes put on by the contractor unless all the chutes are braced).
• Always order 10% extra concrete to allow for an uneven sub grading, spillage and the spreading of the forms.
• Do not spray water on top of fresh concrete until the surface has hardened.
• Joints in flatwork should be a maximum of 4 feet apart and every 3rd joint should be an extension joint.
• Fiber mesh-synthetic fibers provide excellent shrinkage crack control and increase flexural and compressive strength of the concrete.

Proper placement and consolidation of concrete alone will not allow the concrete to perform at its best. Concrete must be properly CURED. Curing is the maintenance of a satisfactory moisture content and temperature in the concrete during a period of time immediately following the placing and finishing so that the desired properties of the concrete can develop.

Methods of Curing Concrete:

• Curing Compound sprayed on the surface of the concrete as instructions prescribe (compounds should be approved by ASTM C-1315).
• Covering the concrete with wet burlap.
• Cover the concrete with plastic (be careful, this can discolor if placed on wet concrete).
• Spray the concrete with a fine mist of water periodically. (Make sure the surface of the concrete is hard before you spray and do not allow the water to pond on the surface).

Sealer Compounds approved by ASTM C-1315 should be used to help prevent the penetration of salts and other chlorides into the surface of the concrete.

ALL CONTRACTORS SHOULD READ from the American Concrete Institute:

• Cold weather concreting ACI 306
• Hot weather concreting ACI 305