Designed for Quality – The ATC Williams Laboratory

Atc News Insidelab 1

The ATC Williams Laboratory has been strategically developed to produce high quality, sophisticated testwork that is fit-for-purpose and adds high value to any geotechnical or mining project.

With a focus on obtaining reliable material parameters for design, our lab serves the fields of geotechnical engineering (traditional soil mechanics), tailings engineering, and slurry and rheological engineering. We offer high-caliber and quality service to clients across Australia and the globe.

The history of our lab

ATC Williams’ philosophy is that to do good geotechnical design, you need good input parameters. For geotechnical engineers, this means laboratory testing. We decided early on that the optimal way for us to control the quality of results was with our own laboratory.
In the early eighties, the office and lab were in a converted home in Bonbeach, in the southeastern suburbs of Melbourne. We were growing quickly and therefore moved the lab into an adjacent purpose-built facility. When the team outgrew the Bonbeach office, a move to Mordialloc was necessary. The laboratory relocated to a larger building on Beach Avenue (not to be confused with the main office on Beach Road).

At the time, we were impressed by the amount of space and storage. Still, the Peter Principle of Laboratories ensured that “sample testing and storage requirements always expand to overfill the space available!” Therefore the lab is an evolving space that is readjusted to increase capacity when new equipment arrives, or more staff are required.

From the outset, our standards of practice and quality were set at a very high level. In line with these aspirations, the lab obtained and has since maintained NATA registration.

Meet the lab team

John Walker is our laboratory manager and is a registered NATA assessor which requires him to regularly audit other labs across Australia.

John is competently assisted by Luke Renkin and Sampath de Silva, and a group of technicians, including undergraduate engineering students. We’ve found that the lab provides an ideal environment to start professional careers by obtaining a fundamental understanding of geotechnical engineering.

Dr Michael Munro, a Senior Engineer in the Melbourne office, provides technical oversight of the advanced geotechnical testwork activities. Michael commissioned our triaxial equipment and more recently, soil-moisture characterisation testwork.

Dr Behnam Pirouz has developed and oversees the detailed slurry (rheological) testing components in the lab – a fitting role, given that Ben completed his PhD in beach slope assessment.

Atc News Insidelab 2

Comprehensive Laboratory Services

The lab offers a comprehensive range of test procedures that support the range of our engineering projects, with development and refinement of many procedures using the wealth of experience and knowledge of our staff.

TML (Transportable Moisture Limit)

TML tests are used to determine safe moisture content levels for shipping of granular products (typically ore concentrates), given the potential for these materials to liquefy in a ship’s hold under heavy seas, with potential catastrophic effect. We provide this service for many major mining companies across the world. Our testing includes the exotic-sounding Fagerberg test procedure (not to be confused with the Atterberg Limits test!).

Triaxial Cells

Triaxial testing requires a specialised test procedure using highly regulated equipment. Triaxial test results are essential for geotechnical design, particularly for foundations and embankments, and most importantly under seismic loading conditions. ATC Williams has committed the capital to establish the equipment required for both static and cyclic triaxial tests within a temperature-controlled environment. The triaxial testing is already highly utilised with more gear ordered in response to demand. We are excited about increasing our capacity in this area.

Rowe Cell Oedometer

The Rowe cell oedometer is a piece of testing equipment rarely seen in a commercial laboratory. This is an advanced test used to establish compression and consolidation parameters and is particularly relevant to characterising mine tailings starting from slurry form. Each test typically starts by pouring slurry into the cell to settle, then load in increasing increments from 1 kPa up to around 640 kPa. It is not a test than can be rushed: most tests take weeks, and some run for months, based on the permeability of the tailings material.

In the 80s, the original cell was one of the first of its type in Australia outside of Universities. Testing involved manual readings and hand calculation of results, so you can imagine that the introduction of spreadsheets was a revelation!

The lab now runs three 200mm diameter cells all in corrosion-resistant stainless steel, with data loggers for automated results collection. Labour and computational components are reduced but not so the time required for the actual test.

Slurry Rheology

Rheological parameters are required as input for the design of slurry transport systems (e.g. pumps, pipelines, flumes/channels), as well as to estimate beach slope profiles of discharged tailings. Beach slope assessment is a critical parameter to support the design of storage systems containing thickened tailings.

For many years, the lab used a Haake rheometer for the measurement of these parameters. More recently a specialised pipe-loop is used to investigate special cases where the Haake rheometer cannot return reliable results (e.g. for segregating slurries). The test procedures used in this area are unique and uncommon in similar labs around the world.

Tailings Tests

There are no recognised national or international standards for some tests, and ATC Williams has developed several in-house procedures for the preparation and testing of tailings samples (usually commencing from an initial slurry state). Procedures include:

  • Slurry sample handling and pre-flocculation (an art form in itself)
  • Initial settled density (drained and undrained)
  • Shrinkage limit density
  • Segregation behaviour.

The lab has a Tempe cell, which is used mainly for the determination of the Soil Moisture curve utilised in modelling of unsaturated soil (tailings) behaviour.

Basic Soil testing

We do a full range of NATA registered soil tests, namely: particle size distribution, plasticity (Atterberg Limits), compaction, soil particle density (SG), and permeability. We also do more specialised tests, including vibrating table (maximum/minimum density) and pinhole dispersion.

Field and In-Situ Testing Equipment

The lab is the custodian of an extensive array of field and in-situ test equipment such as penetrometers, shear vanes, permeability tests, rock shear tests, sampling tools and others. These assess strength and potential access to the surface of very soft tailings deposits. We also offer field density testing (and do dust off the nuclear density meters from time to time).

To enquire about the ATC Williams laboratory, please contact John Walker on (03) 9590 9222, or Dr Mike Munro or Dr Ben Pirouz on (03) 8587 0900.