Few things are more aggravating to produce on a worksite than concrete. Bags of cement, sand, aggregate (gravel) and possibly other additives must be delivered to the construction area. A supply of clean water is also necessary, along with a concrete mixing hopper. Even after all the dusty and heavy ingredients have been loaded into the hopper, one small error in the wet/dry ratio can render an entire batch of concrete unusable. One common solution to this messy and time-consuming problem is ready mix concrete.
Ready mix concrete manufacturers use the same cement, aggregate, additives and water, but the product is created off-site and usually delivered in bulk to the construction zone. Large trucks with revolving hoppers replace the smaller versions used directly on the site. The concrete is ordered directly from a local supplier who can create custom blends or bulk orders. Some contractors may need more aggregate in their concrete, for example, or special curatives added for faster drying times.
Companies that make ready mix concrete often belong to professional organizations that oversee all of their members. Any innovation in the industry can be quickly implemented or discussed during regular meetings. Other issues which can affect the industry are maintaining professional standards, environmental concerns and local laws concerning heavy transportation.
It is not unusual to find ready mix concrete companies in the industrial sections of cities or in rural areas. Massive piles of sand, gravel and other aggregates are usually stockpiled on the grounds, along with earthmoving equipment and delivery trucks. Companies which specialize in this concrete may also provide gravel for roadway construction and cement for other construction projects.
Ready mix concrete is usually ordered in units of cubic yards or meters. It must remain in motion until it is ready to be poured, or the cement may begin to solidify. The concrete mix is generally released from the hopper in a relatively steady stream through a trough system. Workers use shovels and hoes to push the concrete into place. Some projects may require more than one production run, so more trucks may arrive as needed or additional batches may be produced offsite and delivered.