What Does Static Push Mean?
Static push refers to the push exerted on the cone of a static cone penetration test (CPT) apparatus to push it to the desired depth. The cone is pushed into the ground at a controlled rate of 2 cm/sec. CPT is a method of geotechnical investigation for testing bearing capacity and penetration resistance of the soil.
This test is best performed in soft clay, silt, medium, and fine sands and is unsuitable for gravelly soil or soil with SPT (standard density test) value > 50.
Trenchlesspedia Explains Static Push
CPT uses static push to measure cone tip pressure, sleeve friction, tilt angle and pore pressure. This test along with other tests is conducted prior to carrying out trenchless installation projects. The test is performed by pushing the standard cone with a base area of 10 cm2 and an angle of 60°, into the soil at a rate of 10 to 20 mm/sec. After installation, a sounding rod is pushed into the soil at a steady rate of 10 mm/sec in order to advance the cone.
The readings are noted in the gauge at regular depth intervals during penetration. It can also be used to measure pore water pressure, shear wave velocity, and temperature. The geotechnical investigation reports carry all information required to make decisions regarding the method and tools most suitable for a project.