Teretek resin injection is a ground improvement technology that can be used to mitigate liquefaction with minimal disruptions.
There is a growing demand for liquefaction mitigation beneath existing structures. Resin injection is one of only a few practical and non-invasive methods that are currently available.
After a decade of researching and developing Teretek resin injection, Mainmark can claim a high level of accuracy in its design. Mainmark has also worked with international experts throughout the development of this technology. The performance of the resin injection has thus been tested across a wide range of geotechnical conditions.
Mainmark uses Teretek resin injection for ground improvement applications such as increasing bearing capacity and liquefaction mitigation.
Development of Teretek Resin Injection
In 2013, Mainmark took part in industry-leading research to test shallow ground improvement methods. These research trials attracted practicing engineers and academics from all over the world. During the course of this research, Mainmark trialed and tested Teretek Resin Injection technology.
There has also been a commercial application of Teretek for ground improvement. From 2015-16, three adjoining large format retail buildings were re-levelled and repaired. These buildings had suffered liquefaction-related damage caused by the Canterbury Earthquakes (up to 160mm of differential settlement across the 5400m2 combined building footprint).
Teretek resin injection was used to improve soil density and stiffness and mitigate liquefaction.
The results showed that Resin Injection was one of the best ground improvement techniques from the trial and significant improvement can be achieved with Mainmark’s methods
The resin injections resulted in increases in qc1ncs (i.e. the clean sand equivalent of the corrected CPT tip resistance) in the order of 40%, and decreases in calculated settlements in the treated zones of 40-80% at 100-year return periods of shaking (Traylen et al. 2016, Hnat et al. 2017).
The project therefore demonstrated that resin injection is a viable technology for ground improvement, and is particularly useful for liquefaction mitigation or ground densification beneath existing structures. Furthermore, the low level of intrusion required to carry out the process was a particular advantage for this operation, as the three retail outlets (including a large supermarket) were able to continue trading uninterrupted through the busy Christmas trading period.
In the research trial, there was on average, there is a 65 to 75% increase across all three sites.
After four years of development and international peer-reviewing processes, the development of Teretek as a ground improvement technology was complete.
Due to the proven results of this testing, our technology features in Module 5 — a guide for engineers on best practice and consistency in ground improvement design.
These guidance modules were co-developed by the Ministry of Business, Innovation & Employment (MBIE) and the New Zealand Geotechnical Society (NZGS).