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Here is a gold mining project that Terra's Structural Engineering team worked on in Waikaia (just north of Invercargill). This is the largest gold dredging operation in the country. ​ Terra’s task was to come up with a safe way to move the gold dredge from one part of the Waikaia river to another part, some 5km away. The dredge weighs 360 Tonne and is built on top of a pontoon which allows the dredge to float.

Our structural engineers designed a frame to float the dredge over the top; the water would be pumped/drained out and this would allow for the dredge to settle down onto the frame.

Once the dredge was settled onto the frame, two large trailers were backed under the frame which then hydraulically lifted the dredge off the frame. The trailer was then towed by large Kenworth trucks out of the hole and moved down the road.

Our engineers undertook extensive analysis of the frame to ensure the weight of the dredge did not deflect more than 12mm at one point. Feedback from our clients was that it went perfectly!

All very interesting – and a HUGE success. For experts in engineering problem solving, contact our structural engineering team.

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