Specification of Lead Rubber Bearing (LRB) Bridge
Lead Rubber Bearing (LRB)
Lead Rubber Bearing (LRB) consists of rubber pads and steel laminated with steel plates for installation to the structure. Rubber material from LRB acts as a spring. LRB is very laterally elastic but very rigid vertically. High vertical stiffness is achieved by having a thin layer of rubber reinforced by steel plates. Both of these characteristics allow the insulator to move in the lateral direction with relatively low stiffness but carry significant axial loads due to its high vertical stiffness. Lead cores provide damping with plastic deformation when the insulator moves laterally in an earthquake.
similar to HDRB, and Elastomer Bearing Pad, multiple layers of elastomeric material and steel slabs are vulcanized with a central core.
Generally, rubber to make LRB is a natural rubber with a hardness level of 45 to 55, more flexible than elastomeric bearing pads. Lead Core on the part of LRB, is a type of metal material with plastic properties, that is when exposed to vertical impact pressure, will produce plastic shear deformation which is limited by steel plate and natural rubber. And the result is that the bearing hysteresis curve is changed and the bridge pads have a very good damping effect. So when experiencing high energy compression, a bridge bearing with a central central core can produce large deformations and consume most of the energy, to avoid damage. What's more, the LRB used for bridges or construction is different. For the bridge, it also needs a small vibration absorbing capacity and rotation performance at the supporting position. So, when using, you need to integrate various practical situations to choose the most profitable bearing. In general the LRB surface is round but can also be made square with more than Lead Core. We also provide other rubber products for construction of bridges and buildings.
