LRB vs FPS: Which Seismic Isolator is Better?

When choosing seismic isolation for your building, you'll face a fundamental decision: Lead Rubber Bearing (LRB) or Friction Pendulum System (FPS)? Both are proven technologies with decades of successful applications, but they work on fundamentally different principles and offer distinct advantages.

How LRB Works

Lead Rubber Bearings consist of alternating layers of rubber and steel plates with a central lead core. The rubber provides flexibility, the steel plates ensure vertical load capacity, and the lead core provides energy dissipation (damping). During an earthquake, the rubber deforms laterally, and the lead core yields, absorbing seismic energy as heat.

How FPS Works

Friction Pendulum Systems use a curved sliding surface with an articulated slider. During an earthquake, the building slides along the concave surface, with gravity providing the restoring force. The friction between the slider and surface dissipates energy. The isolation period depends only on the radius of curvature, not the building weight.

Head-to-Head Comparison

When to Choose LRB

LRB is typically preferred for residential and commercial buildings where consistent performance at all earthquake levels is critical. It activates immediately at any ground motion level, provides excellent self-centering, and has the most extensive track record worldwide.

When to Choose FPS

FPS excels in heavy structures like bridges and industrial facilities. Its weight-independent period makes it ideal when consistent isolation performance is needed regardless of varying loads. However, its friction threshold means it may not activate during small earthquakes.

Not sure which is right for your building? Run our free analysis to get a personalized recommendation based on your building's specific parameters.

🌐 Read this article in Turkish: LRB vs FPS İzolator | Also available in Turkish on sismikizolasyon.com