THE DEVELOPMENT OF NEW CONSTRUCTION METHODS ABOUT SHAKE PREVENTION DUCT STRUCTURES

Experimental studies are carried out on the newly devised method of shake-proof ducts with earthquake resistance, and it is verified whether the method will satisfy the allowable values of the construction guidelines in Japan. Based on the results, the aim is to improve the workability of the new method. The jig was installed on two shake prevention duct structures, fixed, and loaded horizontally. The vertical load was approximately 1kN assuming an actual duct, and the horizontal load was 4.9kN according to the construction guidelines. The interlaminar deformation angle and deflection angle was measured to determine if the allowable values are met. The construction methods about shake prevention duct structures was to install two pillars and connect the duct ring to the pillar with a plate. Bolts ware used to connect the duct ring to the plate and the pillar to the plate. Nine different tests conducted with parameters such as pillar height and cross-sectional standard. For a pillar length of 1500 mm, the allowable value in the Japanese construction guidelines was met, but for a pillar length of 2000 mm or more, it was difficult to meet the allowable horizontal displacement. However, it was possible to meet the allowable value by increasing the pillar cross section, increasing the bolts connecting the pillar to the plate, and reinforcing the base of a pillars.