Experimental Studies on Load-Carrying Capacities and Joint Stiffnesses of System Scaffolds

• Main Authors: Che-Huei Yu, 虞哲煇
• Other Authors: 彭瑞麟
• Format: Others
• Language: zh-TW
• Published: 2017
• Online Access: http://ndltd.ncl.edu.tw/handle/bvh4aa

碩士 === 國立臺北科技大學 === 土木工程系土木與防災碩士班 === 105 === System scaffold is primarily formed from the joining of main pipes, ledgers, braces, and basse screw jacks and can be used to support scaffolding or formwork. The load-bearing capacity of system scaffold is affected by the strength and stiffness of connectors; however, the scarcity of mechanical test data on connectors has affected the precision of system falsework design analyses and resulted in a risk of collapse. This study tested the load-bearing capacity and stiffness of various connectors commonly used in system scaffold in Taiwan and further tested the load-bearing capacity of double-layer, single-row, single-span system scaffold. These tests were conducted to examine the effects of changes in connector strength and stiffness on the load-bearing capacity of system scaffold. The results of these experiments indicated that a looser allowance between main pipes resulted in decreased load-bearing capacity, with a maximum decrease of approximately 65%. Changes in the depth of insertion of the main pipe into casing tubes resulted in changes in load-bearing capacity from −74% to +132%. The plate flatness and degree of inclination of screws in the base jack showed a more evident effect on main-pipe load-bearing capacity, whereas connection allowance and depth of insertion showed weaker effects on load-bearing capacity. The stiffness of a level surface of revolution in the connection between ledgers and the main pipe was 11.31 times higher than the stiffness of a vertical surface of revolution. The stiffness of a surface of revolution around the main pipe could not be determined from the connection between braces and the main pipe, whereas the stiffness of a vertical surface of revolution reached 100 kN-cm/rad. Furthermore, when the double-layer, single-row, single-span system scaffold featured braces, the load-bearing capacity increased by 1.04 times.