About the author:

Shanghai Tunnel Engineering Co., Ltd., Shanghai 200032,China

Abstract:

In side⁃wall concrete pouring projects of underground engineering, the disk lock scaffold wasoften used as a lateral support structure to bear lateral horizontal loads, which required to concerned itslateral bearing capacity and lateral stiffness. The lateral load⁃bearing behavior and vertical load⁃bearingbehavior of disk lock scaffold were significantly different. The experimental research, finite elementanalysis and theoretical analysis on the lateral bearing performance and calculation method of disk locksteel tubular support frame were conducted . The full⁃scale bearing capacity tests of the disk lock steeltubular support frame under lateral load showed that the support frame exhibited the deformationcharacteristics of large lateral displacement in the middle and small lateral displacement in the upper andlower parts. The failure modes included the bending and shearing failure of the lower standards, thecompression and buckling failure of the diagonal braces, and the failure of the tie components. The linearbeam elements were adopted to simulate the steel tube components, and the spring elements were used tosimulate the semi⁃rigid characteristics of the disk lock joints. The established finite element model couldaccurately simulate the lateral bearing performance of disk lock steel tubular support frame. Through thesimply supported beam model with spring supports, the maximum lateral displacement of the disk locksteel tubular support frame under lateral load could be calculated. According to its stiffnesscharacteristics, the lower ground anchor beam was simplified as a hinged support, while the upper walltie was simplified as a spring support, so as to establish a simply supported beam model with a springsupport, which was used to calculate the maximum lateral displacement of the disk lock steel tubular support frame under lateral load.