Seismic isolation systems comprising a load-bearing surface having a polymeric material

A seismic isolation bearing assembly comprising:

• a first isolation bearing plate;
• a second isolation bearing plate;
• and
• a moveable bearing element disposed between the first and second isolation bearing plates, each of the first and second isolation plates comprises a solid material and a surface facing the other isolation plate comprising a polymeric material different from the solid material, said polymeric material being tacky and causing a reduction in sliding, stopping, and/or skipping of the movable bearing element as it moves across the surfaces of the first and second isolation plates, wherein the polymeric material comprises a 100% polyurea polymer, has a hardness (Shore D) of about 45-55, a tensile strength of about 2800-3200 pounds per square inch (psi), a tear resistance of about 500-600 pounds per linear inch (pli) and a percent elongation of about 400-500, and said polymeric material has a thickness in the range from about 0.5 mm to about 5 mm and is sufficiently durable to have a useful life on the isolation bearing plates selected from the group consisting of a) about 5 years and b) greater than about 5 years.