A shear test determines a material’s ability to withstand perpendicular, or upright, stresses. Such testing can be used for a wide range of purposes and can involve a wide range of equipment. Site geological evaluations and materials testing for commercial products are two common applications. When a controlled testing environment is required for validity, technicians can perform this test to exacting specifications for product control or forensic purposes.
A shear test can be used to assess the properties of rock and soil at a site in geotechnical engineering. Shear stress can be applied to a building’s underlying substrate during earthquakes, severe weather, and other events. Engineers must determine whether it is capable of withstanding the stress without failing. If it isn’t, designs may need to be tweaked, such as adding bedrock anchors to keep a structure stable. Knowing about soil conditions can also help with disaster preparedness.
Engineers can conduct a shear test in the lab or in the field. They use soil and rock samples collected from various locations on the site and subject them to compressive forces to see how they react. The test equipment can keep track of the amount of pressure applied, allowing the engineer to pinpoint the point of failure. In cases where there are questions or concerns about the testing’s quality, tests may be repeated to confirm the results. Avalanche risk is assessed using similar testing by people like rangers.
Materials testing with products like plastics and films uses a different type of shear test. These may have to withstand perpendicular forces while still remaining operational. When a test material is sandwiched between two plates and pressure is applied, technicians can see if it ruptures or wrinkles. The point at which the material begins to deform is recorded in order for technicians to develop precise technical specifications. Some materials may not be suitable for certain applications if they fail at low pressures.
Shear test procedures may be regulated by regulatory agencies. These ensure that companies use the same methods for all of their testing, allowing tests from different facilities to be compared. The development of universal technical specifications is also aided by standardization. Because the shear test results can be generalized, companies reviewing lists of materials and their accompanying data can understand them. To determine if they have or can make materials that will meet their needs, facilities preparing bids can look over the tolerances listed.