Mainmark’s Ground Improvement and Liquefaction Mitigation solution formally recognised as a geotechnical innovation

– internationally peer reviewed report now available.

It’s been nearly four years in development, and with extensive trials and testing now complete, Mainmark is proud to announce the internationally peer reviewed report for our Resin Injection Ground Improvement Research Trials has been released with the results hailed a success.

The findings regarding engineered resin technology for ground improvement and liquefaction are a significant development for the ground engineering industry which now has a new ground improvement methodology to consider when addressing at risk buildings and structures susceptible to weak soil conditions. The full report is now available for review on the New Zealand Geotechnical Society website here.

The resin injection research trials, jointly funded by New Zealand industry bodies, MBIE (Ministry of business, Employment, and Innovation) and ECQ (Earthquake Commission), were carried out in the Christchurch Red Zone and peer reviewed by a team of notable national and international academics and engineers.

The report reveals Mainmark’s engineered resin injection technology has the potential to deliver substantial benefits as a viable, low impact solution for ground improvement and its use is particularly exciting for earthquake prone regions (both regionally and internationally) who are grappling with damaged buildings and structures affected by seismic liquefaction.

We are confident that Mainmark’s Ground Improvement and Liquefaction Mitigation solution, using our proprietary Teretek® engineered resin, will pave the way forward in addressing a range of situations where structures have been affected by weak soil, including liquefaction. In fact, Mainmark’s engineered resin injection technology is a proven, non-invasive, affordable, fast and clean liquefaction mitigation solution that can be applied beneath existing buildings.

We would like to take this opportunity to thank the independent peer review panel; Professor Kyle Rollins from Brigham Young University and Dr Sjoerd Van Ballegooy from Tonkin & Taylor Ltd; and also the supervising engineers, Nick Traylen from Geotech Consulting and Rick Wentz from Wentz Pacific Ltd. In addition, we thank Dr Liam Wotherspoon for his work on the cross-hole geophysics, Land Test and McMillan Drilling for providing CPT rigs, DMT testing and borehole drilling, as well as Geotechnics Ltd for the plate load testing and Central Laboratories for soil testing services. Tonkin & Taylor Ltd provided resource consents for the project, KOA Ltd undertook survey work and set-out control for the project, and The University of Canterbury provided bender element testing.

The research trials were an enormous undertaking for Mainmark, in terms of time, money and effort, and Mainmark’s team, led by Russell Deller, Theo Hnat, Jamie Bawden and Brad McNally are to be commended for their work on the project, both in the field and behind the scenes. We couldn’t be prouder of their achievements.

Mainmark’s research and development of engineered resin for ground improvement and liquefaction has also been shortlisted for the Technical Innovation Award at the 2017 Ground Engineering Awards, with winners to be announced in London this July.

About Mainmark’s ground improvement and liquefaction research trials and testing:

Following the 2010 and 2011 earthquakes in the Canterbury region of New Zealand, over 15,000 homes were demolished mainly due to liquefaction. While it is unusual for contractors to invest in the research and development of new methodologies, Mainmark had a theory that engineered injection resin technology could be used for seismic liquefaction, but required proof of its capabilities before it could be considered for mainstream use. The business then took the initiative to invest time, money and effort into commissioning a series of peer reviewed research trials.

In 2013, the New Zealand Earthquake Commission (EQC) sponsored a series of ground improvement trials. One of these trials involved tests on a small panel of Mainmark’s engineered resin. The panel was tested in a number of different ways, including earthquake simulations with full strength shake and explosives. The outcome from these initial trials was positive with the ground noticeably improved, but due to the relatively small panel size further testing was required to gather more robust data.

In 2016 the Christchurch Red Zone Trials commenced on an area of crown land suffering from significant liquefaction. With the support of MBIE and EQC, Mainmark embarked on an expanded trial to test its proprietary resin injection technology under the supervision of a team of Engineers and independent international peer reviewers. These tests continued to investigate the use of expanded resin injections as a ground improvement solution through pre and post ground investigations, which consisted of geophysical testing including CPT, cross-hole shear-wave velocity testing and seismic dilatometer testing (DMT). These tests were carried out to approximately two metres below the ground improvement zone with final testing undertaken using hydra-excavation where the resin injection panels were analysed to determine the outcome of the resin structure. The trial outcomes found greatly improved ground density and stiffness as well as significantly reduced surface damage and an improvement in the static bearing capacity.

Laurie Andrews MainmarkBy Joe Glanville

Joe Glanville is Mainmark’s ANZ Commercial Manager. He has over 15 years’ experience in the Construction Industry, acquiring broad commercial, construction and project management skills.