Bearings

To the eyes of a profane observer, bridges and large civil engineering structures seems like static works, withstanding gravity and environmental effects thanks to their fixity and stiffness. Nothing could be wrong more than that: as the structural engineer well knows all structures are deforming, deflecting or twisting under the effect of the superimposed loads, furthermore they vary their length due to temperature variations, creep and shrinkage of the concrete.

Structural bearings indeed are the devices allowing the correct transfer of the loads between the structural members, permitting at the same time all the necessary relative movements, translations and rotations. In accordance with the definition given by the European Standard EN 1337 “Bearings are elements allowing rotation between two members of a structure and transmitting the loads defined in the relevant requirements as well as preventing displacements (fixed bearings), allowing displacements in only one direction (guided bearings) or in all directions of a plane (free bearings) as required”.

ALGA has always been a vanguard in the field of structural bearings and its Managing Director Dr. Ing. Agostino Marioni is the main creator of the European Standard EN 1337, being its Chairman since the beginning of the works.

The following Bearing types are available:

ALGAPOT Pot Bearings
SFERON Spherical Bearings
LINEAR Rocker Bearings
ALGABLOC Elastomeric Bearings
ALGAFLON Elastomeric Bearings with PTFE
EBP Antivibrating Bearings
FSK e MSK Fixed and Movable Shear Keys
Special bearings: with monitoring instruments, injectable, double acting, dielectric are also available.

ALGA utilizes for the bearings also innovative sliding materials:

• XLIDE MTF granting a wear resistance more than 5 times and a compressive strength more than twice that of PTFE
• HOTSLIDE suitable for applications with temperatures exceeding 48°C (limit temperature for PTFE) and up to 100°C

Research and quality control

The development of innovative bearings was made possible by the great investments in research and the strict contact with the main European research centres like Politecnico di Milano.
All structural bearings are subject to quality assurance according to ISO 9001 and, where applicable to CE marking according to EN 1337