What Does Core Sample Mean?
A core sample can be defined as cylindrical sections of sub-surface earth material retrieved using core cutters or core barrels. They are removed during overcoring operations to study the lithology of the soil and rock through which the borehole will pass.
Core samples are very important for sampling and conducting soil investigation in order to select appropriate boring methods for laying pipelines. Trenchless methods such as horizontal directional drilling (HDD), horizontal auger boring (HAB), microtunneling and pipe jacking use different types of drill bits and cutters to bore through soil or rock.
Trenchlesspedia Explains Core Sample
Core barrels are used to bring up rock samples from the drilling operation. Other equipment used for core sample recovery are core puller and core shovel. Core samples can be obtained through different methods such as gravity coring, vibracoring, diamond drilling, and percussion and rotary drilling. Core samples can provide data regarding particle size distribution, moisture content, bulk density and shear strength. The American Society for Testing and Materials (ASTM) has many tests that can be conducted based on site conditions and project requirements in order to get a comprehensive idea of prevalent sub-surface soil conditions.