An Experimental Investigation of Unbonded Laminated Elastomeric Bearings and the Seismic Evaluations of Highway Bridges with Tested Bearing Components

Table 3

Equivalent damping ratio.

Test specimen	75% ESS	100% ESS	150% ESS	200% ESS	250% ESS	300% ESS	350% ESS	400% ESS
Y1-4/30-UB	0.158	0.167	0.236	0.301	0.367	0.404	0.421	0.440
Y1-6/30-UB	0.159	0.164	0.240	0.323	0.383	0.410	0.411	0.434
Y1-8/30-UB	0.150	0.156	0.240	0.330	0.386	0.418	0.430	0.436
Y1-8/45-UB	0.156	0.160	0.244	0.340	0.396	0.422	0.438	0.446
Y2-8/3-UB	0.154	0.157	0.287	0.381	—	—	—	—
Y2-8/30-UB	0.155	0.158	0.271	0.366	0.397	0.428	0.438	0.441
Y2-8/45-UB	0.161	0.166	0.281	0.371	0.412	0.440	0.443	0.452