Just how much tension can a wall tie take? If it’s a Cintec tie – lots.
In this video we complete a wall tie test demonstrating epic performance. Our wall tie technicians have installed some M6x225mm Cintec ties on this project for testing prior to important refurbishment work. After curing for 1 week our MD returned to site to test these. Watch as we use an independently calibrated tension rig to measure the performance.
As you will see, there is no sign of the tie being ‘pulled-out’ at all, as a tension of over 5kN is applied. This is remarkable because in service, these ties would share the work. That means that each tie would be subject to no more than 1.5kN in this exposed position, on the East coast of Yorkshire.
Choosing the right wall tie for the job
Why use a more expensive Cintec tie of such very high performance, if only 1.5kN would be a good wall tie test? The reason for the upgrade is because of the very poor condition of the bricks and bed-joint material. The bricks are already cracked and weathered, which means that a mechanical, friction-fix, or resin bond tie could ‘pull-out’. The Cintec Sock Anchor is installed in a larger diameter pilot hole. This, combined with the intimate bond around the entire inflated sock, reduces bearing stress at the tie/substrate interface. In effect the wall tie is grabbing more material, so that the load is shared out – magic!
Of course, we could have just tested the tie to 1.5kN, but a safety factor is sensible, so the structural engineer asked for 2.5kN. We couldn’t resist testing just or two to double that – just for demonstration (the test anchors are not part of the actual installation, so ‘over-stressing’ the substrate was not relevant for this isolated case).
Our surveyors know the intricacies, advantages and disadvantages of all remedial wall tie and anchor systems. We will use one that is suitable and sufficient, without breaking the bank. But as seen in this video, when there are technical obstacles – they have the answers.
Needs help with a potential wall tie issue? Phone or email us via our contact page.