An Experimental Study into the Behaviour of Tube and Fitting Scaffold Structures under Cyclic Side and Vertical Loads

Ma’En Abdel-Jaber,Mu’Tasim S Abdel-Jaber,Robert G Beale

doi:10.3390/met12010040

Abstract

The United Kingdom and European codes for the analysis and design of tubular scaffold structures assume that the scaffolds are subjected primarily to vertical loads and to horizontal loads at right-angles to the scaffold. The effects of dynamic loading caused by large winds tend to be ignored and the code analyses often only require static loading on the structures to be considered. To investigate side loads, a scaffold frame built according to the UK standard was made and inserted into a testing rig. Five different load combinations were made to determine the behaviour of the scaffold under different side loads, which were varied cyclically to simulate different wind loads, especially when vertical loads were also applied. The results showed that cyclical loads affected scaffold behaviour, especially when the bases of the scaffold standards were not tied to the base at the bottom of the test rig. Changes should be made to the UK and European codes BS EN 74.1, BS 5975 and BS EN 128 11-1 for the design of scaffold structures to increase safety.

Highlights

This paper extends the research into tubular scaffold connections undertaken by the authors Abdel-Jaber et al [1] into the behaviour of a tubular scaffold system under combinations of variable side loads combined with vertical loads
As increased horizontal movement occurred with higher side loads, the authors are confident in the results
Applying a horizontal cyclic load sequence meant that the maximum vertical loads had to be reduced so that frame did not distort

Summary

Introduction

Abdel-Jaber et al [1] undertook experiments on the three commonest connections used to connect sections of the scaffold They are the sleeve coupler used to join two tubes together, the right-angled coupler used to join two tubes at right-angles and the swivel coupler used to join two tubes joined at angles that are not at 90◦ to each other. Cyclic tests conducted by Abdel-Jaber et al [1] showed that the mean looseness of sleeve couplers was 0.038 radians, that of right-angled couplers was 0.017 radians and that of swivel couplers was 0.0469 radians. Its original date was of publication was 1982, it has been updated regularly, with the most recent being the version defined in 2016 as it prescribes construction processes

Methods

Results

Conclusion