Drilling Services

We provide specialist ground investigation and testing services including:

1. Geoprobe direct push environmental sampling and drilling.
2. Cone Penetrometer Testing (CPT).
3. Seismic Cone Penetrometer Testing (SCPT).
4. Push tube soil sampling
5. Inclinometer monitoring.
6. Cost effective site investigation services.
7. Geotechnical investigation services.

Geoprobe Direct Push Sampling and Drilling

RDCL operates a direct push rig mounted on a New holland LS180 Skid Steer to reach those difficult to access sites. The 6600 has a 20T pull and up to 16T push capability, when anchored. We have the equipment from Geoprobe to offer a variety of soil sampling systems, including DT 32 and Macro-Core. We also have a detachable DH66 Drop Hammer for SPT counts, with split spoon soil sampling in one go.

Geoprobe Systems, operating out of Kansas, USA, is the leading designer and manufacturer of direct push machines, equipment and tooling for the environmental and geotechnical industries. They are the supplier of Geotech AB of Sweden’s CPT and SCPT testing systems. With these two companies combined, and our local supplier Enviroquip, RDCL is well supported to deliver:

Push tube soil sampling

With the DT 32 and Macro-Core systems we have the ability to quickly and efficiently recover soil samples, giving it the edge over conventional drilling methods. The added benefits of direct push-type soil sampling include the ability to recover continuous soil cores through holes barely larger than the core itself.  The main advantages are:

• Significantly lower setup and overall costs,
• No drilling fluids to dispose of, contain or contaminate,
• No drill cuts to dispose of,
• Quicker setup and overall times.

Cone Penetrometer Testing (CPT)

Cone Penetrometer Testing (CPT) offers fast, reliable and repeatable ground condition testing, with digital outputs to speed up processing and analysis. The Geotech AB piezocone run by RDCL is a state of the art device utilizing cordless technology (radio/sound signals) for data transfer, leading to better probing productivity. With push technology, the result is generally lower cost to the client and lower environmental impact than conventional drilling methods.

Piezocone CPT(u) testing measures pore pressures (u) in addition to tip and friction resistance providing a “complete” suite of data for geotechnical assessment. CPT produces a continuous, detailed log of ground conditions and better repeatability of measurement compared with conventional SPT (Standard Penetration Test).

Seismic Cone Penetration Testing (SCPT)

SCPT comprises of running a tri-axial accelerometer down hole in conjunction with the CPT(u). NZS1170.5:2004 states that “The preferred site classification method is from site periods based on four times the shear-wave travel time through material from the surface to underlying rock”. The SCPT method has proven to be a very accurate and reliable tool in the determination of Vs and Vp profiles.

Another important use of estimated shear waves velocities in geotechnical design is in the assessment of liquefaction susceptibility of soils. Since the shear wave velocity is influenced by many of the variables that influence liquefaction (eg, void ratio, soil density, confining stress, stress history, and geological age) it is an excellent index of liquefaction susceptibility.