Excavation Structural Support
Brisbane, Australia: Shallow Soil Mixing with ALLU Power Mixer, Telegraph Road Open Level Crossing Replacement
The project site was located at the intersection of Telegraph Road and Lacey Road in northern Brisbane. The mass soil mixing and stabilization focused on improving the foundation material such that settlement and differential settlement at the bridge abutments and approach would be minimized. Geo-Solutions teamed with Menard Bachy to develop an acceptable laboratory mix design and Quality Control plan that would meet the client's specifications prior to production. This method of mass shallow stabilization, although widely used within the US, was one of the first to be implemented in Queensland, Australia.
Once approved by the Brisbane City Council (BCC), Geo-Solutions provided the ALLU Power Mixer and Site Manager for both supervision and technical support, where Menard Bachy supplied the batch plant, support equipment and all labor necessary.
The specified requirement for the soil mixing (SM) was a minimum unconfined compressive strength of 375 kPa at 28 days.
This project was a success and completed on time and met all of the client's design requirements.
- To improve the bearing capacity of native soils both along the bridge abutment and approach.
Description of Work
- Client: Brisbane City Council (BCC)
- Engineer: Aurecon
- Work completed
- Total Volume: 13,300 Cu. Meters
- Max Depth: 2m
- UCS Target: 375 kPa
- Types of soil stabilized:
- Cl Silty Clay, medium plasticity, some fine sand
- Fast track schedule for the completion to allow for the continued construction of the abutment wall and placement of imported fill to build the approach ramp.