An Innovative Geotechnical Monitoring System For Soft Ground Treatment On W2B Pacific Highway Upgrade Project

This paper presents an innovative geotechnical monitoring system for soft ground treatment for the on-going Woolgoolga to Ballina (W2B) Pacific Highway Upgrade project. This $4.3 billion project is Australia‟s largest regional infrastructure project and will upgrade about 155 kilometers of highway to four lane, divided road. The project starts about six kilometers north of Woolgoolga (north of Coffs Harbour) and ends approximately six kilometers south of Ballina.

One of the major challenges on this project is the construction of road and structures over soft compressible ground with a total length of over 25 kilometers in 1 to 2 years‟ time. During construction, the short term slope stability and settlement performance will be monitored by a total of 1500 instruments taking up to 10 million measurements. This will enable the team to take early preventive actions to maintain slope stability, to protect public safety and existing structures during construction, and to ensure that the projected long term settlement is within acceptable limits.

Following the standard file based approach, the instrumentation data was estimated to produce up to 80,000 files to be manually handled. To efficiently process the data, limit the potential for manual errors and reduce the turnaround time, Pacific Complete developed an instrumentation and monitoring (I&M) system using its project integration platform, automatically warehousing the data on the project servers and presenting real-time dashboard to the team using Qlik Sense and its GIS extension. In addition to providing high availability, transparency and reliability of the information, this system is expected to realize savings of $2.5M in manual handling of the information alone. The system can be progressively extended to support direct data download from automated instruments, more instrument types, single and multiple instruments alerts, and refined graphs to suit the requirements of linear infrastructure geotechnical monitoring.

Compared to the traditional copy and paste method using Excel, the benefits of this I&M system include fast processing of massive data on a daily basis, automatic integration with GIS maps, chainage, instrument type and locations, lateral displacement plots, settlement plots (both predicted and measured) in longitudinal sections, ratios of lateral to vertical displacement and fill height plots, pore pressure plots and existing road/structure movement plots.