Finger joints



Expansion joints


  • Typical movements: 100 to 800 mm

  • Modular design

  • No lifting equipment needed to install finger plates

  • Easy replacement of finger plates


mageba TENSA-FLEX sliding finger joints are bridge expansion joints for movements of up to 800 mm. They consist of steel finger plates and counter pieces which are vulcanised in durable elastomer. The finger plates are pre-tensioned downwards as a result of a slight inclination at installation, and thus maintain constant contact with the counter pieces at the opposite side of the bridge gap. This prevents them from protruding above the driving surface due to bridge settlements or rotations. The finger plates are non-rigidly secured to the bridge by anchor bolts, reducing the effect of moment loading on the structure. They can be doweled directly to a specially prepared concrete surface, or bolted to a separate steel substructure which is concreted to the main structure. The orientation of the fingers, in the direction of vehicle travel, minimises noise emissions and maximises driver comfort. A drainage channel, hanging beneath the joint, discharges to the bridge’s drainage system.


TENSA-FLEX RC sliding finger joints are suitable for use under heavy traffic. Their special doweled connection system makes them particularly useful where the impact on the main structure should be minimised. The system is designed on a modular basis, allowing individual finger plates to be quickly replaced as required.


Drainage channel


Hose connection point to simplify cleaning of the drainage channel


Phased replacement of an old expansion joint (middle) with a new TENSA®FLEX joint (behind), with the help of the “Mini-Fly-Over” system (front)


Illustration of step-by-step joint replacement using the “Mini-Fly-Over” system


Preparation of the connection surface


Placing of the finger plates