You have Questions? We have Answers! Read FAQ’s about Concrete, What You Will Need for the Do-It-Yourselfer, The History of Cement and Concrete, Mix Information & Everything You Will Need to Complete Your Project.
The invention of Portland Cement is credited to an English stonemason named Joseph Aspdin. He obtained a patent for Portland Cement in 1824. He called his new product Portland Cement because when hardened, it resembled the color of natural stone quarried on the Isle of Portland in the English Channel. Concrete was used on a very limited basis from its inception through the late 1800’s. It was mixed on-site until about 1920 when the idea of mixing at a central location and then hauling it to the project site became popular. This innovation improved quality and consistency and was so convenient for contractors that it became the preferred method of producing and using concrete. The term “Ready Mixed Concrete” caught on because the concrete was already mixed when it arrived at the jobsite.
Yes, there is a difference. Cement, or Portland Cement, is a finely-ground powder made from limestone and other raw materials. The materials are blended together and fired in a kiln at extreme temperatures. The resulting stone sized pieces, called “clinker,” are then ground into a fine powder that we call Portland Cement. Portland Cement is the active ingredient in concrete. Concrete is the product used in buildings, bridges, road paving, sidewalks, patios, etc. Concrete is a mixture of Portland Cement, water, aggregate (sand and stone), and miscellaneous chemical admixtures. Concrete is mixed at a concrete plant facility and delivered to customers in revolving drum truck mixers, also referred to as concrete trucks or mixer trucks. Concrete is sometimes generically referred to as “ready-mix” because it is ready to use or already mixed upon arrival at the project location. Many concrete producers have incorporated various forms of this terminology into their company name. It’s common to see names such as Ready Mixed Concrete Company, Hank’s Ready Mix, Smith Redi-Mix, etc.
Fresh (wet) concrete is highly alkaline and can cause skin irritation, severe third degree chemical burns and serious eye damage. Always wear protective gloves and glasses or goggles when working with wet concrete. Waterproof boots must also be worn if standing or walking in wet concrete. If clothing becomes contaminated with wet concrete, it should be removed at once and the affected body area(s) washed immediately. Flush eyes with clean water immediately after contact. Seek medical attention if you have persistent or severe discomfort.
Durable, long-lasting, low-maintenance concrete begins with selecting the proper mix design. To resist the affects of snow and ice, freezing and thawing, and deicing chemicals, the American Concrete Institute and National Association of Home Builders recommend using a mix designed for a minimum compressive strength of 3500 psi and a maximum water-to-cement ratio of .45. Loveland Ready Mix Concrete personnel are available to assist you with selecting a mix design suitable for your application. Please contact us for assistance.
Concrete can be a do-it-yourself project if recommended concrete practices are followed. Some things to consider are: subgrade preparation, finishing methods, jointing and curing. Concrete is a perishable material so it is imperative that it be placed and finished in a timely manner. Additionally, most concrete producers assess “holding charges” if concrete trucks are held at the delivery location in excess of a predetermined amount of time. Concrete is very heavy so it is recommended that you have adequate assistance and the proper equipment and tools when placing and finishing. Should you decide to hire a concrete contractor, it is recommended that you verify your contractor’s references.
We will need to know who, where, when, what and how much. Please be prepared with an accurate delivery address, date and time of delivery, quantity and mix design. Loveland Ready Mix Concrete personnel are available to recommend a mix design suitable for your application. Please contact us for assistance.
Concrete is sold by the cubic yard, in one-quarter cubic yard increments. Concrete producers usually require a minimum purchase of one cubic yard as smaller batches are sometimes less consistent. All measurements should be converted to feet then multiplied, and finally, divided by 27. An example would be a patio measuring 10’ 6” long x 14’ 3” wide x 4” thick. The example would be calculated as: (10.5 x 14.25 x .33) ÷ 27 = 1.83 cubic yards. It is common to add ten or fifteen percent to small loads and five to ten percent to larger orders to compensate for subgrade settlement, uneven subgrade, spillage and waste. In the example given, adding fifteen percent would bring the total to 2.1 cubic yards. The total should then be rounded up to the nearest one-fourth cubic yard, or 2.25 cubic yards. Please see our yardage calculator on our home page for more information about concrete “yield.” You can also contact us for assistance.
Concrete can be placed at various temperatures if precautionary measures are taken. In extremely cold weather, concrete should not be allowed to freeze until it has gained sufficient strength to withstand the damaging affects of freezing. Concrete will lose its workability and set up considerably faster in hot weather.
Many concrete mixes can be placed successfully with a concrete pump. Some considerations that may affect pumpability are type of pump, cement content and aggregate size. It’s best to discuss mix selection with your concrete pumping contractor.
There are different types of concrete cracks. The most common of these is related to the natural shrinkage of concrete as it cures and dries. Shrinkage cracking can be controlled or “hidden” by following proper jointing techniques. Different factors and conditions can contribute to each type of cracking. It is important to understand these potential causes and take appropriate action to prevent cracking.
Surface deterioration is usually referred to as scaling. Scaling is a local flaking or peeling of the finished, hardened concrete surface, resulting primarily from multiple freeze-thaw cycles. The condition can be aggravated by the presence of deicing materials such as salt. Any product that is intended to melt ice and snow can contribute to scaling. Even products labeled “Safe for Concrete” can contribute to scaling. The probability that scaling may occur can be reduced or eliminated by using a durable concrete mix and following recommended concrete placing, finishing and curing/sealing practices. Loveland Ready Mixed Concrete personnel are available to assist you in selecting the concrete mix and curing and sealing products for your project. Please contact us for assistance.
There are different types and causes of concrete discoloration. Dark, shadowy areas may appear if the fresh concrete was placed over alternating wet and dry areas of the subgrade. Darker areas are typically located where the subgrade was too wet or actually muddy. Temporarily covering concrete with poly sheeting or construction blankets can also cause the hardened concrete to be darker in appearance. Another possible cause of dark, mottled areas is the uneven application of curing/sealing products. Curing/sealing products should be applied as uniformly as possible with a nozzle that will produce a fine spray or mist. There can also be differences in coloration between concrete slabs placed on different days. This is usually due to slight variations in temperature and weather conditions from day to day. The potential for discoloration can be greatly reduced by following recommended placing, finishing and curing practices.
During periods of moderate to warm weather, new concrete could be opened for pedestrian traffic in twelve to twenty-four hours, or when the surface becomes “scuff resistant.” A general guideline is that new concrete should not be opened for vehicular traffic for a minimum of seven days. This seven-day period can be significantly reduced by using a faster setting, stronger concrete mix. Please note that concrete gains strength more slowly in colder weather so more time may be needed before putting your new concrete into use.
Fiber reinforcing will reduce the potential for cracking and improve the impact and abrasion resistance of your concrete slab.
References are provided courtesy of the National Ready Mixed Concrete Association (NRMCA).
