Quick Enquiry Call Us

Search

If you cant find what you’re after please don’t hesitate to contact us.

Select Region

Please select the global region website you'd like to view.

Asia
Japan

Quick Enquiry

Submit your enquiry using our online form and include a brief message about the type of issues you are experiencing. One of the Mainmark experts will contact you as soon as possible.

Hidden
This field is for validation purposes and should be left unchanged.

Project Profile N15W022

Stabilisation of Subsided Ground

Sub-industry
House
Problems
Subsidence
Location
NSW
Year
2014
Solutions
Ground Improvement
Technology
Other

The problem

Mainmark corrected the recurring subsidence that caused a dangerous potholing. Originating from mine subsidence, the pothole had recurred due to voiding of non-cohesive soils approximately 7m to 8m below the ground surface within old and abandoned coal workings. Correction was effected by acrylic resin injections.

The solution

The objective was to stabilise the ground to nullify or greatly reduce the likelihood of further subsidence. This was to be effected by the filling of the existing network of voiding and the plugging of the collapsed mine workings, preventing a recurrence of the sink holes and associated subsidence, at a depth of between 7m and 8m below local ground level.

The Result

The original pothole was likely to have been caused by a localised collapse in mine workings at a level of approximately 8m below the surface. A previous attempt had been made to remediate the sink hole by the use of concrete fill.

The soil below the pothole was suspected to be a loose sand material, which had the potential to migrate via a small localised zone of voiding above the original drift, which may not have been fully stabilised by the concrete backfill. Mainmark technicians caried out a trial application in a relatively small test section of the affected ground. When this proved successful, they proceeded to inject the whole problem area, using a combination of urea silicate and acrylic resin, Tam GeoTek AC. The soil was injected at between 7m and 8m depth.

The chemical grouts were injected via four drilled and speared injection points. This equated to grouting 25 cubic metres of solid material into the target zone. The injection of the grout nullified the likelihood of additional non-cohesive soil migrating into the drift. Consequently the subsidence and the pothole problem are considered very unlikely to recur.

Resources

Project Resources & Downloads

Stabilisation Of Subsided Ground
Next Project

Large Swimming Pool Re-levelled

Mainmark

© 2024 The Mainmark group of companies. ‘Mainmark®’, ‘Terefil®’, ‘Terefirm®’ and ‘Teretek®’ are trademarks of the Mainmark group of companies.

Mainmark Ground Engineering Pty Ltd
ABN: 51 606 182 503

ISO 9001
ISO 14001
ISO 45001

Residential

Commercial

Infrastructure

Mining

About Mainmark

Our team

Careers

Contact

Technologies

Media & Press

News

Awards

Privacy Policy

Terms and Conditions

Created by Codex

YouTube
Facebook
LinkedIn
Instagram