Drilling Fluids for the Temporary Support of Deep Excavations

Start time: 12.00pm AEDT. Learn about the considerations needed when drilling fluids for the temporary support of deep excavations, as well as some common construction risks related to the selection of suitable fluid systems for different ground conditions.
Bored piles under bentonite

The construction of diaphragm walls and large-diameter bored piles is normally carried out using drilling support fluids to temporarily stabilise the deep excavation prior to concrete placement.

In most cases such drilling fluids are either mineral-based slurries (bentonite), polymer support fluid systems or simply water. The working mechanisms of these three fluid types are fundamentally different.

Even though fluid stabilized deep excavations are often not categorized as temporary works, reliable assessment methods and material specifications for the stability evaluation of such deep excavations are required.

Robust design principles for bentonite slurry supported temporary excavations have been developed in the last few decades and the working principles and associated risks of such mineral-based slurries are understood reasonably well. However, polymer supported excavations follow different principles to assess the temporary stability of deep excavations and different assessment methods are required.

The possible fluid related impacts on the permanent design performance of bored piles or other deep foundations need to be considered by permanent works designers to ensure the performance criteria are met.

This webinar will discuss these considerations, as well as some common construction risks related to the selection of suitable fluid systems for different ground conditions. Typical defects caused by the incorrect application of drilling support fluids, and their pro-active mitigation, will also be reviewed.

Speaker: Dr Martin Larisch

Dr Martin Larisch is a Principal Geotechnical Engineer with Jacobs. He has been involved in piling and ground engineering for more than 20 years with technical and operational roles which involved the design and construction of different piling and retention systems for numerous landmark infrastructure and building projects across the Asia Pacific Region.

Martin is also a CPEng with Engineers Australia and has been involved in the development of various industry guidelines and best practice documents for deep foundations in Australia, Europe, North America and New Zealand.

06 / 11 / 2020 - 12:00 pm to 01:00 pm
Registration Closes
06 / 11 / 2020 12:15 pm
Webinar available
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  • Member Rate: $0.00 ($0.00 excl. GST)
  • Technical Society Member Rate: $30.00 ($27.27 excl. GST)
  • Student: $0.00 ($0.00 excl. GST)
  • Non-Member Rate: $30.00 ($27.27 excl. GST)
Key Speaker(s)
Dr Martin Larisch
Engineers Australia
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  • Contact:
    Engineers Australia Member Services
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    1300 653 113
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