Case Study – Campaspe Shire Council

Project Activity:

A 3.2 km section of Granville Road between Looker, McDonald and Tehan Roads, Echuca Village (an unsealed road) was re-sheeted with 40mm Crushed Rock (A Grade – with fines) sourced from the Mt Scobie Quarry and subsequently stabilised using TERRA-3000 (soil stabiliser).

The project was undertaken between Monday, July 20 and Friday, July 24.

The ultimate aims of treatment were to reduce road maintenance cycles, to achieve better results with materials sourced from the Mt Scobie quarry.

Site Visit – Pre Project

Monday, May 4: Andrew Dickey (Terra System) visited Glanville road with Brian Hubbarb, Mick McNair and Rod O’Neill.

Meeting observations (road shoulder samples gathered and later compared to samples supplied by Mick McNair):
– video was taken of the 3.2 km section between Looker, McDonald and Tehan Rds.
– material sourced from the Nanneella quarry was the primary sheeting/re-sheeting material present, although intersections had been patched with a myriad of materials over time.
– with the exception of intersections with Looker, McDonald and Tehan Rds the surface was well stabilised although it was established this was a result of high rotation maintenance.
– water was observed in large pools on the shoulders of the road with some ingress onto the road surface (due to recent and heavy rainfall).
– road level was low and was susceptible to inundation, hence Councils desire to re-sheet.
– we agreed on the need to blend any new and existing materials during stabilisation, Rod and Mick expressed concern that disturbance of the existing stabilised layer be kept to a minimum of say 50 mm.

Testing Performed

Monday, May 4, Andrew returned to the Tongala Works Depot with Mick and was provided samples of:

  • 40mm Crushed Rock (A Grade – with fines) – Source: Mt Scobie Quarry
  • 40mm Crushed Rock (A Grade – with fines) – Source: Nanneella Quarry

for our internal testing.

Tuesday (May 5) We contacted Damian Eastman (Quarry Manager, Mt Scobie & Nanneella Quarries) to obtain any available geotechnical reports on the quarried materials used in Councils re-sheeting activities. The primary success factor when planning treatment with TERRA-3000 is the presence of clay, therefore we were interested in the silt / clay fractions passing 0.075 mm from any available Particle Distribution Analyses. Damian subsequently provided a number of reports prepared by Construction Sciences Pty Ltd. The silt/clay fraction reported for Mt Scobie (17%) and Nanneella (20%) are adequate for treatment. 
We worked with the quarried samples obtained from Mick McNair. We manufactured compacted cores from the materials supplied. Both the Mt Scobie and Nanneella quarried samples were treated with TERRA-3000 and compact well as expected. We tested the capillary rise, swell and particle loss in treated and untreated samples and will report back. Finally we created hybrid test candidates by combining the Mt Scobie and Nanneella samples.

Treated and untreated compressed cores (pucks) were partially immersed in water with untreated cores failing (disintegrating within 3-5 minutes of immersion). The treated cores were then partially immersed in water for 72 hours to observe the capillary action of water on candidate materials, to observe any particle loss, and to measure water absorption and change in weight between 24, 48 and 72 hours.

All treated pucks remained intact, had acceptable capillary rise and had only minor weight gain due to the absorption of water over three days. Importantly none of the treated pucks experienced swelling due to excess absorption of water.

The final photos show only minimal particle loss over 72 hours, most of which is from manual handling of the pucks.

Subsequent experiments in blending the materials had similarly good results.

Project Day One

Rating 4/5 Stars: Overall execution on day one was perfect in all aspects other than the absence of the warmth of the sun. Rod felt he had applied excess water which was true insofar as temperatures remained low during the day and there was little evaporation in play. That said, whilst tracking a little early on day two, the surface benefited from additional rolling and drying time. At any other time of the year. Day one would have rated 5/5 stars for execution.

Project Day Two

Execution speed on day two was approximately 2.5 hours quicker than on day one, which is typical of our experience across a myriad of projects.

The crew required little instruction as the treatment plan was well understood. Given temperatures remained low on day two, Rod was more cautious in controlling moisture and obtained excellent results with more efficiency on the second day.

The re-sheeting material sourced from Mount Scobie was a more inconsistent on the second day with several loads best described as bony (lacking fines, with particle size distributions well exceeding 40 mm).

Increased blending of the in-situ and re-sheeting materials was required to ensure adequate fines.

Rating 4/5 Stars.

Councils Civil Construction Team

We have provided guidance during treatment with TERRA-3000 to many local government and private civil construction crews.

I felt compelled to publicly comment on LinkedIn in tribute to the skill and professionalism of Councils works crew.

“It was my privilege to be on-site with Mick, Rod, Tim, Andrew and of course FJ” – Andrew Dickey

Signage

In consultation with Council the following signage was designed to highlight the project to the community. The signage will also indicate to Councils maintenance team that the section is under observation.

COVID-19 – Impact

Terra System take our public health obligations seriously.

Terra System has a current COVID-19 action plan, lodged with NSW Health.

Under the conditions of the TERRA SYSTEM COVID-19 Action Plan, we keep any customer we have recently visited of our compliance milestones.

Andrew Dickey :

  • Dates of visit: July 19-21 (Sun-Tue).  
  • Testing: Andrew Dickey  was tested for COVID-19 prior to visiting Campaspe Shire (Wed, July 15: Result: Negative*).
  • General: Prior to visiting Campaspe Shire Andrew Dickey was in good health and displayed no symptoms of COVID-19 infection.
  • General: During transit and upon return from Campaspe Shire Andrew Dickey was in good health and displayed no symptoms of COVID-19 infection.  
  • Testing: Andrew Dickey was tested upon return from visiting Campaspe Shire (Wed, July 22: Result: Negative*).
  • Our contact tracing register has been updated for all places visited for accommodation, food and fuel whilst in transit and within Campaspe Shire. These records are available to Council upon request.

Next Steps:

  • If Andrew Dickey develops any symptom of COVID-19 in the next 10-14, Andrew will re-test and inform you of any positive result. (Update: No symptoms present. Follow up test result was negative for COVID-19).
  • If any employee of Campaspe Shire Council with whom Andrew has had contact during his visit should test positive to COVID-19, please inform us immediately by return email. (Update: No report received.)

* Note: test results are obtained via SMS only using a unique passcode. A Negative test result indicates the person tested is not currently infected with COVID-19.

Saving Our Environment – Reducing CO2 Emissions

TERRA-3000 is a carbon neutral stabilisation option.

Our minimal emissions during manufacture and transport to site are 100% off set by our carbon sequestration activities, the purchase of carbon credits and our participation in humanitarian relief efforts.

Comparing stabilisation with TERRA-3000 to Cement stabilisation:

In Australia, during manufacture of TERRA-3000 produces a min. 80 times less CO2 than Cement. During transport TERRA-3000 produces a min. 480 times less CO2 than Cement.

Simple Treatment Plan and Trainer On-Site During Project

Until such time as our customers are comfortable working with our products and methodologies, you’ll find us on-site – by your side every step of the way.

Whilst treatment with TERRA-3000 departs little from regular road maintenance operations, questions do arise and there are tips and tricks that make life easier.

In consultation with our customers we provide a simple and collaborative treatment plan.

Roadmap

Integrated Wearing Course

Globally the most common pavement design when stabilising with TERRA-3000 is to upgrade an unsealed road by application of small gravels during final compaction (rolling) operations to create an integrated wearing course. The small gravels will bond with the TERRA-3000 treated base course and will operate as a single pavement layer improving both the driving experience and longevity of the solution. We would recommend a similar approach for sealed roads, whereby the application of small gravels during final rolling provides the perfect preparatory step before the application of bitumen spray seals or other wearing course applications.

Recycling of End-Of-Life Pavements

Treatment with TERRA-3000 provides a method of re-stabilisation of end-of-life sealed roads. The roads wearing course, base and optionally sub-base can be milled into a single mix suitable for treatment with TERRA-3000. The resulting layer will be highly stabilised ready for the application of a wearing course. Using this method all existing in-situ materials are recycled. Applying the same principles TERRA-3000 is a great solution for heavy patching, whereby damaged pavement can be milled during treatment typically to a depth of 200 mm, compacted in readiness for the application of a new wearing course. The TERRA-3000 treated layer will improve with traffic, therefore stabilisation and renewal of the wearing course can take place at the same time or days apart.

Drop-in Pavement, Pot Hole Repair, Intersection Repair

TERRA-3000 is the catalyst for our award winning Pot Hole Fix solution.

In essence, our Pot Hole Fix is the optimal particle distribution at which treatment with TERRA-3000 will achieve an in-situ modulus (EVD) approaching 150 MN/m2.

We work closely with local quarries to enable Local Councils to develop economical, sustainable and carbon neutral solutions for pot hole repair (15 kg, 20 kg, 1,000 kg variants), as well as pre-mixed (pug-mill) solutions for drop-in roads.