Thin-walled perforated sheeting is used for sound absorption in buildings. The perforation may extend over the whole surface or only parts of the sheeting, e.g. webs. So far only reduction factors for the in-plane stiffness and the bending stiffness of fully perforated sheets with an equilateral triangular perforation pattern are included in EN 1993-1-3 and EN 1999-1-4. These factors only apply to perforation patterns in form of equilateral triangles, because of the isotropy assumed during derivation. Furthermore, the equations provide only information on stiffness and not on the stability behaviour of thin-walled components. The insufficient and misleading formulations of these regulations are overcome by the investigations presented here. Design rules for trapezoidal sheeting which are fully or partly perforated with equilateral triangular or square perforation patterns are given. The design rules take into account the beneficial effect of the post-buckling behaviour of the sheeting. They also cover web crippling at supports or under local loads.
Starting with the basic aspects of the load-bearing behaviour, the parameters requi ... mehrred for capturing the influence of the perforation are defined and determined for the different perforation patterns. By introducing these parameters into the design procedures for the calculation of the load-bearing capacity of thin-walled structural components being at risk of buckling failure, the use of these procedures is expanded to fully perforated structural components. Numerical investigations with the finite-elements-method allow the verification of these theoretically derived calculation procedures.
Based on comprehensive numerical and experimental investigations on web crippling, it can be shown for fully and partially perforated trapezoidal profiles, that the influence of the perforation can be captured by multiplying the capacities according to EN 1993-1-3 and EN 1999-1-4 with a factor Cp for fully perforated profiles and Ctp for partially perforated profiles. A calculation procedure for these factors is given.
The recalculations of more than 600 experimental tests with perforated trapezoidal and corrugated sheeting which were performed since the 1980s at the University of Karlsruhe show the good correlation between the calculation procedure and the test results.