Project 1.5 (2019)

Soil stabilization for unsealed mine-haul roads

Mine haul road network is a critical component of the mining production process. Poor performance of a haul road will impact mine productivity and may incur significant costs for maintenance. The mine haul road is an asset which should be designed to deliver a specific level of performance which has a direct correlation with the complete mining process. A well-built and maintained haul road will enable haul trucks to operate safely and efficiently. However, these roads are usually built as unpaved and as a result, they are highly susceptible for moisture degradation due to direct exposure to rainfall/infiltration specifically in areas where the subgrade soil comprised of either expansive soil, collapsible soil or sulphate rich soil which are high sensitive to moisture. Cyclic and impact loads generated by moving traffic on the moisture weakened pavement cause severe damages that can result safety concerns and frequent road maintenance. Unfortunately current haul road pavement design standards do not account provisions for design and evaluation of road pavements against its greatest ever enemy that is moisture. The proposed project aims to link the knowledge gap inherent in pavement stabilization and performance in order to cater for safer and cost effective haul roads. It will utilize industry by-product to advance towards a novel flyash-stabilized material through an effective application in pavement engineering.

Project Objectives

1. To undertake a review of flyash based soil stabilization and haul road behaviour under climatic and operational loads

2. To develop a suitable experimental approach for testing flyash stabilized soil for investigating hydraulic and mechanical behaviour

3. To evaluate the behaviour of flyash stabilized soil-mix to examine and quantify the stabilization effects under repeated dry/wetting cycles at operational traffic load (simulated) in applicable with haul roads

4. To determine the optimized stabilization soil mix that produce the most effective road performance for mining haul roads

5. To validate the stabilization procedure using trial road construction at mining site

6. To develop a modelling methodology to incorporate flyash based soil stabilization

7. To propose design and construction guidelines for haul roads using stabilization methods

Chief Investigators: 
  • Dr Dilan Robert (LCI - RMIT University)
  • Professor Jayantha Kodikara (Monash University)
  • Assoc Professor Annan Zhou (RMIT University)
Industry partners: 
Partner investigators: 
Michael Shackleton (ARRB Group Ltd)