PURPOSE: To set a vibration-isolating bearing for bridge separately from dampers by a method in which a laminated rubber layer is provided between the upper and lower shoes facing the superstructure, rollers are set between the lower shoe and a bottom slab facing the lower structure, and a high vibration-damping rubber is fixed to them.
CONSTITUTION: A laminated rubber layer 3 to absorb the turning force of the superstructure is provided between an upper shoe 1 facing the superstructure and a lower shoe 2 under the shoe 1. Rollers 5 to support the superstructure in an axially rocking manner are set through a distribution plate 6 between the lower shoe 2 and the bottom slab 4 facing the lower structure. A high- damping rubber 8 is also fixed between the lower shoe 2 and the bottom plate 4. The natural frequency of the superstructure can thus be lengthened by the spring effect 12 of the rubber layer 8 and the displacement of the structure can be lessened by the damping force. The vibration in the axial direction of the bridge can therefore be isolated.
HASEGAWA KINJI
UNJIYOU SHIGEKI
NAGASHIMA HIROYUKI
TAKAKU TATSUMASA
SHIMADA MASAHIRO
NAKAMURA MASANOBU
TSUMURA NAOYOSHI
IDEMA SHINICHI
KOYAMA HIROSHI
NIPPON KOKAN KK
NIPPON CASTING CO LTD