CREatE - A New Strengthening System

Carlos Chastre, Hugo Biscaia, Noel Franco and António Monteiro 

Successful structural rehabilitation uses adequate techniques and materials with good performance in order to increment the structure’s service life and reduce its environmental footprint. A new strengthening technique with extraordinary performance was developed at Department of Civil Engineering of the Faculty of Sciences and Technology of the Universidade NOVA de Lisboa (UNL). The research programme conducted several monotonic and cyclic tests of retrofitted beams with stainless steel or FRP composites of different fibres (glass, carbon, basalt) using different techniques.

In this video a selection of 6 experimental tests of RC bems will be presented.

Traditional Strengthening Systems using stainless steel or carbon FRP composites are compared with the NEW strengthening system developed in this research. All the 6 beams have identical cross-sections, the same size and were tested until rupture in a 4-point bending test system. The RC beams are identical and have the same class of concrete and of reinforcing steel. The strengthening bars have a similar axial stiffness and the materials used as strengthening bars were Stainless steel & Carbon FRP composites. The traditional strengthening systems used were: EBR (external bonded reinforcement) & NSM (near surface mounted reinforcement).

The NEW Strengthening System was tested with both materials: Stainless steel & Carbon FRP composites. The experimental results show a very good mechanical behaviour and an extraordinary performance:

  • the debonding rupture mode was eliminated;
  • the ductility was incremented;
  • the performance of the strengthening bars was totally exploited.

APPLICATIONS

This new strengthening system opens a wide field of new applications and can be applied to different structural elements: beams, slabs, columns, walls, arches, foundations, etc. and materials: concrete, steel, wood, masonry, etc. Furthermore, the initial stress in the strengthening bars can be subsequently modified.

This new strengthening system has a patent pending.

Contacts us: CREatE.s.system@gmail.com