Compressive strength is a measure of a material’s ability to withstand compressive forces, where it is squeezed laterally. Materials testing can determine the compressive strength of a material in optimal conditions, using a specialized device that applies known pressure loads to materials of interest. There are a number of applications where assessments of this property are important, particularly with building supplies, which need to be sturdy enough to withstand failure during and after construction.
Concrete, insulating materials, stone, and various forms of wood can be tested for compressive strength. In the testing, technicians will take note of when signs of fatigue like cracking, bending, and pitting appear. They also record the failure point, where the material breaks down. Multiple tests may be run to confirm the initial findings and generate a range of readings. Especially with natural materials like wood, which may not always be consistent, it is important to find the range in which the material usually sits to come up with a reasonable rating.
Materials can be subjected to tremendous squeezing forces in structures, where the weight of the structure creates intense lateral pressure, especially during events like earthquakes and heavy storms. Compressive strength can also be a concern with vehicles and craft, ranging from space shuttles to sailboats. These craft need to be able to handle varying levels of pressure at different times during operation without failing, and thus the construction materials used must be carefully tested.
A compressive strength rating can help an engineer decide on the best choice of material, after considering other factors like flexibility and resistance to corrosion. Charts with data on common construction materials are available through professional and trade organizations that work with construction and building materials. It is also possible to get product specifications from a manufacturer who can provide detailed information about the properties of the materials it processes and produces. This information can include a discussion of testing methods.
In manufacturing, periodic testing is used for quality control. Technicians want to make sure that products are consistent as they come off the line, and can provide test results to concerned customers. At locations like construction sites, workers can also run spot testing before starting projects, to confirm that, for example, a batch of concrete meets the needs of a given application. If the material fails under testing, it may be defective, and the construction company could be entitled to a refund or replacement from the manufacturer.
