Wednesday 12 July was a momentous day - the Mega-Bridge at the Boyanup-Picton Road interchange (a.k.a. the longest bridge in the South West) had its very first precast concrete headstock shell lifted into place via crane.

These headstocks are critical for supporting the mammoth superstructure and - to do the job safely - they are designed to be beasts of their own!

In fact, each precast headstock weighs a whopping 67 tonnes. What is that in terms of the world’s largest land mammals, we hear you ask… it is as heavy as approximately 10 fully grown bull elephants!

Getting these elephantine headstocks lifted requires the use of an even heavier piece of machinery: A 350-tonne mobile crane. In addition to being raised up and then lowered into the right spot, 77 cubic metres worth of concrete then needs to be filled in to ensure it is secure. If you are still playing the ‘comparison game,’ that is more concrete than would be required to fill in an average-sized backyard swimming pool. Once the concrete is poured, the headstock will sit nice and snug, secured over the top of the three support columns.

“It’s exciting to see the precast concrete headstock shell in place,” said Jackson Lingwood, Construction Manager - Structures and Bridges. “At 21 metres in length each, it’s no mean feat to crane-lift the headstock into position. There’s a lot of planning and logistics that goes into it.”

What comes next? With two shells cast so far and 15 more to go, and one headstock installed at the site with 10 more to deliver, there is still plenty of heaving lifting awaiting the BORR team before the Mega-Bridge is fully up and ready.


 The 350t crane in action lifting the first precast headstock into place