In the field of structural engineering, elastomeric bearings play a crucial role in the stability and durability of constructions.
In this article, we will delve into what these bearings are and their role in civil engineering projects. We will also explore the UNE-EN 1337-3:2005 standard, highlighting why at SERVOSIS we ensure strict compliance with the necessary standards.
What is an Elastomeric Bearing?
Elastomeric bearings are ingeniously designed devices used to absorb and distribute loads in a structure. To be more precise, when a structure begins to function, it experiences various movements and deformations caused by temperature changes, its own weight, and the overloads it is exposed to. To cope with and withstand these changes, it is necessary to have support elements that allow for these movements without causing damage.
These devices, made from high-quality elastomers, have unique properties that allow them to perform crucial functions in civil engineering.
Below, we detail what they are:
Unique Properties of Elastomeric Bearings
Capacity to Absorb Seismic Movements
Elastomeric bearings are distinguished by their intrinsic ability to dissipate the energy generated during seismic events. This is achieved through the controlled deformation of highly resilient elastomers, which absorb the kinetic energy associated with seismic forces.
The implementation of these bearings minimizes the transmission of such forces to the main structure, thereby mitigating the destructive effects of earthquakes. The dynamic response of the elastomers contributes to the effectiveness of this system by damping oscillations, preserving structural integrity, and reducing risks associated with seismic events.
Flexibility and Deformability
The intrinsic ability to deform significantly without compromising its structural characteristics allows elastomeric bearings to accommodate structural movements, such as thermal expansion or contraction, without imposing excessive loads on the main structure.
The controlled deformability of these materials ensures essential adaptability, preserving the integrity of the structure and reducing the likelihood of damage or structural failures due to unforeseen movements.
Vibration and Noise Isolation:
In urban environments and vibration-sensitive structures, elastomeric bearings play a crucial role by providing effective isolation against vibrations and noise. The ability of elastomers to absorb and dissipate vibrational energy minimizes the transmission of these unwanted disturbances to surrounding buildings.
This is achieved through the elastomeric material's ability to convert vibrational energy into controlled deformation, thereby preventing the propagation of annoying vibrations and preserving the quality of the living environment.
Low Transmission of Horizontal Loads:
Strategically designed, elastomeric bearings provide selective resistance to horizontal loads, allowing the structure to expand and contract in response to lateral forces without inducing damage.
The inherent low lateral stiffness of these bearings facilitates the adaptation of the structure to horizontal movements, such as those caused by strong winds or seismic events.
By minimizing the transmission of horizontal forces to the main structure, stability is preserved and efforts that could lead to structural damage or the activation of safety systems are reduced, thereby contributing to the long-term durability and efficiency of the infrastructure.
SERVOSIS and the ME 408 Machine for Testing Elastomeric Bearings
The ME 408 elastomeric bearing testing machine from SERVOSIS is a monoblock servo-hydraulic drive system specifically designed to conduct tests according to the UNE-EN 1337-3 standard. It performs shear modulus, shear bond, and compression tests, respectively.
The system includes:
- Two high-capacity double-acting linear hydraulic actuators (6 MN) for applying axial load.
- One double-acting linear hydraulic actuator (1.5 MN) for applying lateral displacement to the specimen.
- Equipped with Moog servo valves for control and integrated linear displacement sensors.
- The force is measured using a load cell in the lateral actuator and pressure sensors in the high-capacity actuators.
This set of features makes the SERVOSIS machine a high-precision and innovative tool in the market, capable of meeting the most demanding standards and ensuring maximum accuracy in the execution of tests.
We share a video with our machine
UNE-EN 1337-3:2005 standard:
The UNE-EN 1337-3:2005 standard specifies the requirements and test methods for elastomeric bearings in bridges and other structures.
When reviewing the UNE-EN 1337-3:2005 standard, we observe a variety of tests classified into two categories: "initial" and "routine."
The "initial" tests are essential for obtaining the CE certification initial product certification and must be carried out in a laboratory accredited by ENAC o una acreditación europea equivalente dentro de la red de entidades ILAC.
As for the "routine" or follow-up tests, they are essential for maintaining certification as they are considered necessary for product quality control. These tests can be performed internally, provided that the testing equipment is calibrated and technical competence is demonstrated.
SERVOSIS and the importance of complying with the UNE-EN 1337-3:2005 standard:
At SERVOSIS, we know that complying with the UNE-EN 1337-3:2005 standard is essential for elastomeric bearings due to its rigorous technical specifications.
This standard sets criteria for evaluating mechanical properties, fatigue resistance, dimensional stability, sliding capacity, and compatibility with materials and structural systems.
All of this ensures that elastomeric bearings meet the necessary performance, strength, and durability standards for their function in structures.
Therefore, the ME 408 control system, developed exclusively by SERVOSIS, ensures compliance with the regulations. Distinguished by its high range, it competes on equal terms with the most prestigious international manufacturers in terms of precision, resolution, and response speed, thanks to over 35 years of experience in the mechanical testing sector.
