Portable concrete barriers (PCBs) have significantly improved the safety and efficiency of construction sites. Although these concrete barriers are primarily designed to prevent errant vehicles from hitting construction workers, the dynamic side deflection of the barrier keeps the impact to a minimum.
By using longer barrier segments, the deflection of the barrier can be minimized by using a more flexible construction that can develop its own dynamic lateral deflections at the bending moment.
Deflection is a limiting factor so that walls that withstand a combined axial load and a bending moment can also be checked for deflection. They can gain capacity by increasing the wall thickness and the concrete compressive strength.
Reinforced concrete walls should be designed following ACI318, but the technical specifications require reinforcement of both concrete and masonry foundations and walls. In some cases, masonry and concrete foundations contain a nominal amount of steel reinforcement to control cracks. This strength construction method is used in the construction of concrete barriers with a maximum capacity of 1,000 cubic feet per square metre.
Precast concrete elements are incredibly dense and the process used to make them makes them an ideal choice for the construction of concrete barriers.
The density of precast concrete elements effectively reduces noise and creates privacy when used as a barrier in large construction projects. This density is likely to be used in communities facing a motorway.
Precast concrete barriers are made in a central mixing plant and brought to the construction site in a ready-to-use condition. This type of concrete requires the use of vibrations, but the time required for transport is ensured by using a mixture that can harden before undue delays occur.
It has a high strength required by columns, ceilings, bridges and other structures, and architectural concrete allows the use of professional stamping pads. Stamped concrete is usually used for driveways, terraces and interior floors that require an aesthetic appearance.
Mega concrete projects use prestressed concrete, where the bars used in the concrete are loaded. This concrete mixture has high workability but requires the use of high-strength steel bars and a large amount of water. Precast concrete elements are produced with a mixture of prestressed and re-tensioned concrete with high strength and long service life.
The units are assembled on-site and the process consists of shooting the concrete under high air pressure, which results in simultaneous placement and compaction. Shotcrete differs from other types of concrete in the way it is applied.
The advantages of precast concrete elements are because they are manufactured according to individual specifications.
The most common use
Many road authorities use concrete barriers, which are a combination of high-performance centre barriers and high-performance concrete barriers. The 75 mm thick asphalt coatings anchoring the sides of the high-performance central barrier do not detach from the concrete in crash tests with tractor-trailers. Most road authorities do not consider it necessary to use a thicker barrier or to reinforce the reinforcement near the joint.
Efficient and long-lasting
Precast concrete elements are resistant to many microbes that occur in water bodies because they are exposed to rainwater. There is also less decay, which could potentially lead to the exposing of the internal steel, reducing the risk of rust formation due to the exposing. There are also no internal reinforcement bars that are exposed to and susceptible to corrosion and other forms of corrosion such as rust and corrosion of steel.
The main advantage of precast concrete elements is that they can withstand tasks and applications every day without any problems for years.
Could your construction business be more efficient with precast concrete barriers?