TensionCam M45 nuts installed on Älvsborgsbron

Inaugurated in 1966, Älvsborgsbron has in the years since become a beloved fixture on the Gothenburg skyline. But landmark aside, the suspension cable bridge also serves as a crucial link for thousands of people every single day. And with so many relying on it on a daily basis, safety and stability are always of the highest priority.

The roadway is suspended by the two cables and their thirty clamps each. The bearing capacity of the clamps is enabled via M45 stud bolts. And to avoid the risk for cable clamp slippage, achieving the correct clamp load – 400 kN or 40 ton each – of the bolts is critical.

Late 2023 Trafikverket therefore decided to launch a pilot project with TensionCam as all bolts and nuts were already scheduled to be replaced over three years starting in 2022. The scope: To install TensionCam M45 nuts on the cable clamps and thereby enabling clamp load measurements of these critical bolt joints at installation and during inspections.

On May 16th 2024 the six TensionCam nuts were successfully installed and pretensioned. This very special installation on work at height was carried out by our partner Alticlimb AB of Sweden. They also performed the clamp load measurement with the TensionCamequipment.

”We are excited about the TensionCam concept from this pilot project. It really gives valuable information on the actual installed clamp load thereby enhancing the quality of the bolt installation”, says Martin Peoples and Per Forsberg at Alticlimb.

Via the clamp load measurement several important experiences have been gained, for example on initial relaxation & creep and neighbour effects.

The next step is a first follow-up measurement later in 2024 to define possible additional relaxation and creep effects. And with the follow-up done we hope that our partnership with Trafikverket and AltiClimb will continue.

For more information, please contact:

Jonas Nilsagård, CEO
+46 734 29 81 55
e-mail: jonas.nilsagard@tensioncam.com