Concrete

Choosing the Right Type of Concrete

Whether you are building a driveway, setting fence posts, or placing a foundation for a large building, you should know that there are many different types, strengths, and compositions of concrete, each with characteristics that make them perform better for different applications.

Strength is usually determined by compression testing, and is expressed in Pounds per Square Inch (PSI). Normal concrete mixes range from 2500 PSI to 5000 PSI, with engineered design mixes of over 10,000 PSI used in specialized applications. Lower strengths are also available for grouts, and used for displacement, block-fill, and filling abandoned utility lines. Here are some common suggested uses for different strength concretes:

Different Strengths

2500PSI Concrete

May be used in driveways, walkways, and even floor slabs on grade. This concrete is usually the cheapest available from batch plants. Used on solidly compacted fill material (subgrade), this concrete performs satisfactorily for these projects, but many professional concrete workers prefer a higher strength product due to warranty concerns, and some building codes may not allow its use for all of these applications.

3000PSI Concrete

In many locations, this is a standard multipurpose mixture for general use in construction. It is durable, has sufficient cement to give it good finishing characteristics, and can be placed fairly wet without sacrificing quality.

3500PSI Concrete

Used for applications where surface spalling is not acceptable, and significant loading is expected. One example would be paving curbs, where heavy traffic may drive on the surface. Other uses include building footings, bond beams, grade beams, and floor slabs where heavy loads may be moved or stored.

4000PSI Concrete

Used for heavy traffic pavement, heavy use floor slabs like shops and warehouses, and concrete footings designed to support heavy loads.

5000PSI and higher concrete mixes

Usually used for specialized construction projects where high impact resistances, very low wear rates, or extreme conditions are expected.

Special mixes

Concrete can be mixed using different types of aggregates that give it different qualities that may make it more suited for specialty projects.