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Video: Interlocking Split Spoon Overview

Reliable, consistent project results when sampling soil require tested, durable tooling. With drill rig and tooling engineers sharing office and shop space, both geotechnical rigs and drilling tools are refined to the highest level to amplify productivity while also making service and support available from one source. Guided by feedback from the field and focused on making your job sampling soil easier, we continually develop and test new and innovative products and techniques for sampling soil – from standard penetration testing, and beyond. And with same-day shipping on most drilling tools, you can save on inventory costs.

Tools for Sampling Soil

Geoprobe® machines outfitted with a DH-Series Automatic Drop Hammer can be used to perform the Standard Penetration Test (SPT). Sampling soil can include either a hollow stem auger setup or our 3.25 in. probe rod system. If you're seeking a competitive advantage, integrating some direct push methods such as out-the-end sampling into long-standing geotechnical practices can save you significant time on jobs.

Geoprobe®3.25-inch Probe Rods

Drilling tools such as the 3.25-inch probe rods are driven to the desired testing depth. The solid drive tip is pulled and a split barrel sampler is lowered. The drop hammer is then placed on top of the rod string and the number of blows to advance the sampler is counted. The solid drive tip can then be placed back in the cutting shoe and the rod string advanced to the next testing depth.

Hollow Stem Augers

Hollow stem augers are turned to the desired depth with a pilot bit blocking the rod ID when sampling soil. The pilot bit is pulled and a split barrel sampler (split spoon) is lowered. The drop hammer is then placed on top of the rod string and the number of blows to advance the sampler is counted. The pilot bit can then be placed back in the augers and the auger string advanced to the next testing depth.

Interlocking Split Spoon

These drilling tools are commonly referred to as a split spoon sampler. Used for sampling with the DH-Series Automatic Drop Hammers and SPT Systems. The SPT blow count is the number of blows of the automatic hammer required to advance the split barrel sampler 12 inches (305 mm).

  • 2.0 in. (51 mm) OD x 24 in. (610 mm) length
  • AW Box at top.
  • Requires Adapter (17320) if used with 1.5 in. probe rods.

Split tube soil sampling system manufactured under U.S. Patent 9,551,188. It is best practice to consult applicable ASTM standards when performing geotechnical investigations.

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“Using Out the End (OTE) sampling allowed us to complete nearly a year’s worth of work in a week. It opened up a fantastic business advantage over others not using the method. Under certain soil conditions OTE and dual tube can be twice as fast as drive and wash. Twice as much data. Twice as many borings. Twice as much vertical feet in a day, putting us on par with traditional auger rigs and then some.”


John Clark, General Manager, EnviroTech Drilling Services, Rhode Island