Elastic energy storage of lead core rubber bearing

What is Lead Rubber Bearing?

Abstract. Lead Rubber Bearing (LRB) has been widely applied for seismic protection of mid and high-rise buildings around the world. Its excellent energy dissipation becomes the most important aspect of this isolation system thanks to the plasticity and recovery behavior of the lead core.

Do lead rubber bearings provide damping under zero and tension load?

Despite current design equations, lead rubber bearings provide damping even under zero and tension load. A new design equation is proposed to estimate the lead core’s yield strength by taking the influential factors into account. The proposed equation can estimate the yield strength of lead cores, on average, with less than 5% error.

How does the yield strength of a lead rubber bearing vary?

The yield strength of a lead rubber bearing varies by increasing the cycles of loading. The lead core absorbs energy by resisting the applied lateral displacement, which causes internal heating. The coupling of the generated heat and partial creeping of lead core reduces the yield strength at higher loading cycles.

What is lead rubber bearing (LRB)?

The demand for high damping isolation system for seismic protection of buildings and bridges is increasing. Lead Rubber Bearing (LRB) is one of base isolation with high damping capability thanks to the main contribution of the lead core during shear displacement and sometimes with a combination of high-damping rubber.

Which component provides a high damping capacity in a lead rubber bearing?

In a conventional lead rubber bearing, the lead core is the key component that provides damping. Lead plugs can provide high damping capacity due to their relatively low yield strength of about 10 MPa and a perfect elastic–plastic behavior .

What is a lead-rubber bearing?

Lead-rubber bearing construction details (Constantinou et al. 2007b) The elastomer rubber layers serve as the “isolation” (i.e., stiffness and fundamental structural frequency reduction) component; lead also contributes to the stiffness of the bearing, but this contribution is relatively minor.