Investigation of Geometric Imperfections of Support Scaffold Systems (No. R895)

Abstract

The report describes the findings from various site measurements of geometric imperfections on support scaffold systems, also known as falsework in industry. The measurements consist of out-of-straightness of the standards (uprights), out-of-plumb of the frame and loading eccentricity between the timber bearer and the U-head. A special-made tool instrumented with a dial gauge was used to measure the out-of-siraightness of standards at the mid-height of each lift. A theodolite was employed to measure the angle difference between top and bottom of the frame in order to compute storey out-of-plumb, and a vernier calliper was used to measure the loading eccentricity at the top. The measurements were taken from different support scaffold construction sites before ihe pouring of concrete, representing actual initial imperfections and loading eccentricity encountered in practice.