A solid, unbroken slab of concrete weighs about two tons (or 4,000 pounds) per cubic yard. Breaking up concrete roughly halves the total weight per cubic yard to about one half ton (or about 2,000 pounds).
You can calculate how much concrete you need for your construction project using this calculator that works in both US Customary Units (feet and inches) and International System of Units or metric units (meters and centimeters) of measurement.
Most concrete purchases will be made in cubic yards, which equates to 27 cubic feet. For example, a project measuring 10 ft in length by 10 ft in width with a depth of 3.5 in will be just over 1 cubic yard. The equivalent to a single cubic yard in metric measurements would be roughly 0.76 cubic meters.
The output of this calculation should make it simple for you to work out the estimated cost of the concrete materials that you require. For more specific pricing, contact your CEMEX sales representative to discuss.
With all the equipment, tools, and materials you need to purchase for your decorative concrete work, it's easy to neglect the obvious - the concrete itself. Yet ordering concrete should never be an afterthought. Because the material serves as the foundation for all your artistry, its quality and suitability for the job are paramount. By not making this purchase a top priority, you are inviting disaster and risk botching the entire project.
Your first step is to find a reputable ready mix supplier who can supply the material you need at the right time and at a fair price. But that's only the beginning. Placing the actual order is where things get complicated, since concrete is not an off-the-shelf product you can simply shop for out of a catalog.
First, Look in the yellow pages under concrete-ready mix. Jot down the phone numbers of 3 or 4 Ready Mix companies. Note the plant locations if that information is given, or call the plants and get their location.
Second, narrow your list down to the two or three suppliers closest to your home (job location). The American Concrete Institute notes that concrete must be discharged form the truck within 1.5 hours of being batched, or 300 revolutions of the truck (whichever comes first)-so the farther away the plant is form your job, the higher the chance for a problem. Also, the farther the delivery distance, the more transportation of the material will cost. Lastly, the farther away the concrete comes from, the more chance of it being late to the job. So getting a supplier who is close to you helps on all three of your goals in choosing a Ready Mix supplier: a product that performs, when you want it, and at a fair price.
Fourth, when you are satisfied you have one or two qualified ready Mix Companies, call those firms for a price based on the concrete you want. Also ask them how many days lead time they need for an order and if you will be able to get the concrete at the time of day you want.
Reputable ready mix suppliers are usually pleased to have a representative come to your home to check your job several days before the concrete pour. Plan for and schedule this visit ahead of time-do not expect the representative to be able to come out the same day you call.
As straightforward as this information is, most dispatchers will say customers calling to order concrete don't know for sure how much concrete they need, don't know if they need any additives, had never considered if the concrete might need to be pumped, and need the concrete tomorrow!
As you might expect, you'll generally pay higher transportation costs the farther the ready mix plant is from your work site. But that's not the only reason to go local, whenever possible. The farther the truck has to travel, the greater the chance of it arriving late to the job.
Once you choose a ready mix supplier, it's your responsibility to communicate your performance requirements for the concrete, both in its plastic and hardened states. Only then can the supplier work with you to provide a mix that will achieve the desired results.
When placing concrete on a large stamped concrete project, for example, you may need to slow the setting time to permit enough time for stamping. Your supplier also needs to know the anticipated exposure and service conditions of the concrete once it's in place, so he can supply you with a material strong enough for the application and advise you on admixtures to use to enhance concrete performance, such as water reducers and air entrainers.
Other ingredients you might want to include in your mix recipe include fiber reinforcement (for slabs on grade), integral colors, decorative aggregates, or special-purpose admixtures such as set accelerators or corrosion inhibitors. "Today's concrete can be engineered to meet almost any requirement, no matter how far out you might think it is," says Sparkman. "The key is to communicate your needs to your supplier so he can help you design a solution tailored to your situation."
"You should know the fundamentals of concrete mix design, but it's best to leave the exact proportions to your ready mix producer," says Sparkman. Then if your supplier gets the formula wrong, you will at least have a basic understanding of how the components in a mix interact so you can help troubleshoot the problem. A reputable supplier will welcome your feedback and modify the mix to meet your needs. In some cases, even slight modifications can make a big difference in how the concrete performs.
Once you work with your supplier to come up with the best mix for your application, the next step is to order the right amount. Errors on the plus or minus side can be equally difficult to remedy. Buying too much concrete is not only a waste of money, but also necessitates finding an environmentally safe way to dispose of the excess. If you're too conservative with your estimate and don't buy enough concrete, you'll be forced to put the project on hold until an emergency delivery arrives - if you're lucky enough to get one on short notice. NRMCA recommends tacking an extra 4% to 10% onto your total estimate to allow for possible errors as well as spillage or over-excavation.
Ready mixed concrete is usually sold by the cubic yard, with the typical truck mixer holding 9 to 11 cubic yards of material. Determining how many yards you need for square or rectangular slabs is fairly straightforward (you can use this concrete calculator to help you do the math). Figuring out how much concrete you need for irregular slab shapes is trickier. When in doubt, ask your ready mix supplier to help you with the calculations.
Use a Local Supplier to Save Hauling CostsAs you might expect, you'll generally pay higher transportation costs the farther the ready mix plant is from your work site. But that's not the only reason to go local, whenever possible. The farther the truck has to travel, the greater the chance of it arriving late to the job.
Confirm your order the day before you want the concrete! This is an absolute necessity since so many orders are cancelled. You can not order a week in advance and then never call back!
Ask the ready mix supplier how many days of lead time are necessary for an order and whether the concrete can be delivered at the time of day you want it (such as before dawn or early evening to avoid placements during the heat of the day). Giving your supplier ample notice will help to ensure priority service and on-time delivery. For additional reassurance, be sure to confirm your order the day before the pour.
For larger projects requiring several truckloads of concrete, also discuss with your supplier the best time sequence for truck arrival. For example, if you estimate it will take your crew an hour to place a full truckload of concrete, then schedule the trucks to arrive an hour apart. Fresh concrete is perishable and will lose quality if it sits in the truck too long. ASTM C 94, "Standard Specification for Ready Mixed Concrete," says that concrete should be discharged within 90 minutes and before 300 revolutions of the mixer after water has been added to the cement.
All the materials in a mix will contribute to the characteristics of the concrete that arrives at your jobsite. Some qualities, such as workability and ease of finishing, are readily apparent as you place the concrete. But others, such as compressive strength and air content, can't be observed. That's why onsite testing of the delivered concrete is important. These tests will assure you that the material you ordered is the same material that arrives in the truck.
Slump (a measure of consistency), air content, unit weight, and compressive strength tests are the most common field tests for determining the quality of freshly mixed concrete. The following ASTM standards give procedures and acceptable time frames for performing these tests, which should be conducted by certified technicians:
The unit weight test will also tell whether you're getting the amount of concrete you paid for because it determines the yield of a sample of the ready mixed concrete as delivered, according to PCA. This is a simple calculation, but requires you to know the unit weight of all materials batched. The total weight information may be shown on the delivery ticket or can be provided by your supplier.
Based on the results of these field tests or external factors, such as long delivery times or hot weather conditions, it may be necessary to add air entraining, water reducing, set retarding, or other admixtures to the concrete prior to discharge. Let your ready mix supplier advise you in such circumstances and take responsibility for fine-tuning of the mix. Your supplier can't be held accountable for the quality of concrete that you alter yourself, such as by adding more water.
People sometimes use cement and concrete interchangeably, but the two are not the same. Cement is the binding agent in both concrete and mortar mix. Concrete contains cement, sand, and, typically, gravel. The cement is activated when water is added to the mixture, and everything solidifies when it dries. Mortar is usually just sand and cement, so it functions more as a paste used to bind building blocks together. 781b155fdc