Introduction to EN15129 Anti-seismic devices

EN 15129:2018 is a European Standard specifying requirements for the design, testing, materials, and performance of anti-seismic devices used in structures to modify seismic response. It supersedes EN 15129:2009 and covers devices for seismic isolation, energy dissipation, and rigid connections, ensuring reliability, durability, and compliance with safety standards. Key applications include buildings, bridges, and civil engineering works, aligning with EU Regulation 305/2011 for construction products.

1. Rigid Connection Devices (RCDs)

1), Function: Constrain relative displacements; include Permanent Connection Devices (PCDs), Fuse Restraints (FRs), and Temporary Connection Devices (TCDs).

• PCDs: Restrain movements in one or two directions, allow rotations/vertical displacements (e.g., moveable/fixed bearings).
• FRs: Sacrificially fail at pre-set force thresholds to enable movement during seismic events (mechanical/hydraulic types).
• TCDs (Shock Transmission Units, STUs): Activate at specific velocities, providing dynamic restraint; require spherical hinges and viscous fluids.

2), Testing: Type tests (service load, break-away, cyclic loading) and Factory Production Control (FPC) for material compatibility and functionality.

2. Displacement Dependent Devices (DDDs)

1), Linear Devices (LDs): Exhibit linear force-displacement behavior (e.g., elastomeric shear devices).

2), Nonlinear Devices (NLDs): Show nonlinear behavior, including Energy Dissipating Devices (EDDs, ξ > 15%) and Nonlinear Elastic Devices (NLEDs, ξ ≤ 15%).

3), Key Features: Stiffness (K_eff,b, K₁, K₂), damping ratio (ϵ_eff,b), and re-centring capability.

4), Testing: Cyclic loading at varying displacements, temperature/humidity effects, and material aging validation.

3. Velocity Dependent Devices (VDDs)

1), Fluid Viscous Dampers (FVDs): Force depends on velocity ( ).

2), Fluid Spring Dampers (FSDs): Force depends on velocity and displacement ().

3), Design Requirements: Stroke capacity, thermal expansion provisions, and buckling resistance for piston rods.

4)), Testing: Constitutive law verification, damping efficiency, and seal wear resistance under dynamic loads.

4. Isolators

1), Elastomeric Isolators:

►High/Low Damping Rubber Bearings (HDRB/LDRB), Lead Rubber Bearings (LRB).

►Provide seismic isolation via low horizontal stiffness; require shear modulus, compression/stiffness tests.

2), Curved/Flat Surface Sliders:

►Use spherical/cylindrical surfaces for pendulum-like motion, friction for energy dissipation.

►Key parameters: restoring stiffness, frictional resistance, and wear tolerance.

5. Combinations of Devices

1), Integrated Systems: Combine RCDs, DDDs, VDDs, or isolators (e.g., sliding bearings with dampers).

2), Design Focus: Interactive effects, load distribution, and compatibility between components.

3), Testing: Full-scale type tests to validate combined performance under seismic loads.

1), Materials:

■Elastomers (natural rubber, polychloroprene), steel, stainless steel, Shape Memory Alloys (SMAs), visco-elastic polymers.

■Compliance with EN standards (e.g., EN 10025 for steel, ISO 188 for elastomer aging).

2), Design Principles:

■Capacity design with over-strength factors ().

■Re-centring capability (e.g., , E_h for isolated structures).

1), Type Testing: Verifies product performance for new designs or modifications (e.g., cyclic loading, temperature effects).

2), Factory Production Control (FPC): Regular tests on production batches to ensure consistency (e.g., compression stiffness, friction measurements).

3), Assessment & Verification of Constancy of Performance (AVCP): Aligns with EU regulations, including initial factory inspections and continuous surveillance.

1), CE Marking: Based on Declaration of Performance (DoP), meeting essential characteristics (load bearing, seismic resistance, durability).

2), Installation & Maintenance: Guidelines for correct installation (e.g., tolerances, accessibility) and in-service inspections (regular/principal checks).

Normative references include EN 1990 (Eurocode), EN 1337 (structural bearings), and ISO standards for materials and testing.

This standard ensures anti-seismic devices enhance structural resilience by modifying dynamic response, dissipating energy, and maintaining functionality during and after seismic events, aligning with safety and performance requirements across Europe.