of fig1 showing an example guide box configuration of the upper base plate portion of the seismic isolation bearing the lower surface 18 of the guide box 1 and two connection plates 6 are visible fig1 is a schematic diagram showing an elevation of the seismic isolation bearing of fig1 in a displaced position the isolation bearing is displaced in the longitudinal direction u2018 x u2019 units the restoring force cause by the displacement is equal to the force across the displaced shear spring s f r k u00b7 x where k is the total shear spring effective spring rate for the isolation bearing while moving with velocity v the dissipative force is f d u03bc u00b7 w f rbs where u03bc is the sliding coefficient of friction w is the vertical load on the isolation bearing and f rbs is the total damping force of the shear spring s the total force across the isolation bearing is the sum of the restoring force and damping components f f r f d fig1 is a schematic diagram showing a plan view of an example embodiment of the seismic isolation bearing with the upper base plate guide box removed for clarity recess 19 is a sliding surface recess that permits the bearing core 15 to slide within the.