Macalloy Surelok™

Macalloy Surelok™ is a revolutionary, engineered solution to Temporary Movement Joints (TMJ), specifically designed to eliminate issues that current TMJ market options present.

Benefits of
Macalloy Surelok™.


  • Cost effective, technical and practical solution
  • Fully sealed system
  • Fully grouted system for permanent locking
  • Reduced site install time
  • Vertical shear capacity without corbels
  • Eliminates all corbels, edge-form drilling, and pre-grout sealing of joints
  • A truly innovative advancement, ahead of all other market options

Temporary Movement Joints (TMJ) are the most complex joints in concrete slabs as they require temporary free movement in two horizontal directions prior to being locked tight for permanent stability and integrity of a structure.

A world leader in the industry, Macalloy Surelok™ is the first solution to provide bi-directional temporary movement and two-axis load transfer, all within a fully sealed component. Macalloy Surelok™ is revolutionary as it offers a range of safety, cost, design and performance benefits.

Developed for the post-tensioning and construction industries, it is the result of years of experience, investment, research, development and testing.

It required a combination of specialist areas of engineering outside of the standard field of structural engineering, using hydraulic engineering to design a movable pressure seal as well as elastomers and polymers to deliver affordability.

The Macalloy Surelok™ solution engineers an intelligent void with a pressure sealed system bridging the joint whilst allowing two-way horizontal movement.

When required, Macalloy Surelok™ permanently locks the joint together with the same approved grout mixture used for post-tensioned tendons. The intelligent void ensures the dowel retains cover for durability and fire within the sleeve across the joint without having to rely on the joint itself being sealed or grouted.

Since 2011, over 12 stages of prototype development have been undertaken against rigorous design and site performance criteria, complemented by product testing at both the University of Technology Sydney and the Western Sydney University.

Macalloy Surelok™ is the tested and proven solution to Temporary Movement Joints and is the answer to your TMJ needs and requirements. The Surelok™ system now comprises two distinct ranges: one for Slab to Slab connections, and one for Slab to Wall connections, for a total of eight unique models.

To find out more, download the Macalloy Surelok™ brochure.

Our Projects

Our supply chain continues to expand via an international network of Macalloy agents and distributors, ensuring continued growth in the global market.