BOILER APPARATUS

PROBLEM TO BE SOLVED: To provide a boiler apparatus which not only can improve safety and reliability upon earthquake occurrence but also has an economical earthquake-resistant structure.SOLUTION: This apparatus includes: a supporting frame 7 constituted of a plurality of supporting columns 1 and a plurality of main beams 2 disposed on the upper and lower portions thereof; a boiler body 4 hung from an upper part of the supporting frame 7; and a vibration preventing damper 6 connecting the boiler body 4 and supporting frame 7. Here, the apparatus has a plural layer structure constituted of a first layer extended from the base of the supporting frame 7 to the lowermost main beam 2, a second layer extended from the lowermost one of the main beams 2 to the following one of the main beams 2, and so on to the topmost one of the main beams 2. In the layer structure, there is provided the vibration preventing damper 6 on: a center of gravity layer in which there is positioned the center of gravity 8 of the boiler vibration resistance structure constituted of the supporting frame 7 and boiler body 4; layers at the positions upper than the center of gravity layer; and the lowermost layer which is in a direction lower than the center of gravity layer and on which the lowermost end 9 of a vertical portion of the boiler body 4 is disposed so that the total sum of yield resistances of the vibration preventing dampers 6 is composed of such proportions that the center of gravity layer has a yield resistance of 3.6-4.4 and the lowermost layer has a yield resistance of 1.8-2.2 when the upper layer has a yield resistance of 1.