Vol. 2, No. 3, pp. 199-223 (2006)
NUMERICAL MODELLING OF TUBE AND FITTING ACCESS SCAFFOLD SYSTEMS
R. G. Beale*1 and M. H. R. Godley2
1Department of Mechanical Engineering, Oxford Brookes University, Gipsy Lane,
Headington, Oxford, OX3 OBP, UK
2Slender Structures Group, OCSLD, School of the Built Environment, Gipsy Lane,
Headington, Oxford Brookes University, Oxford, OX3 OBP, UK
*Corresponding author, email: This email address is being protected from spambots. You need JavaScript enabled to view it., tel(44)1865 483354, fax(44)1865 483637
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ABSTRACT
This paper describes numerical modelling of tube and fitting access scaffold structures according to the new European standard EN12811. Firstly simplified one-and two-dimensional models are described. The results from these analyses are compared with the output from three dimensional finite element buckling and non-linear elastic analyses with good agreement. Bucking analyses show that effective lengths of tube and fitting scaffolds are strongly influenced by the pattern of ties to the building façade and in many cases much greater than those currently assumed in design being approximately equal to vertical tying increments and not the lift height. As a result of the analyses the authors recommend that the maximum vertical tying increments for large tube and fitting scaffolds should not be greater than every two levels. Wind loads parallel to façade were shown to generate uplift on some windward legs of façade braces which could cause premature failure of the scaffold. Current UK design practice which largely ignores the effects of wind loads is unconservative for large scaffolds. Recommendations for improved practice are made.
KEYWORDS
semi-riged connections, bucking analysis, scaffold structures, finite element analysis
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