S.H. COCKING⁽¹⁾, S. PRICE⁽²⁾ and M.J. DEJONG⁽³⁾

⁽¹⁾  MEng Student, Department of Engineering, University of Cambridge, Cambridge, CB2 1PZ, United Kingdom, sam.cocking@cantab.net

⁽²⁾  Consultant, Price & Myers, 37 Alfred Place, London, WC1E 7DP, United Kingdom, SPrice@pricemyers.com

⁽³⁾ Senior Lecturer, Department of Engineering, University of Cambridge, Cambridge, CB2 1PZ, United Kingdom, mjd97@cam.ac.uk

ABSTRACT

Following the collapse of a tympanum pinnacle at Beverley Minster in Yorkshire, a research project was undertaken to investigate the wind forces which act on stone pinnacles. A survey was conducted and the most common failure modes were identified, which highlighted the importance of dynamic forces in addition to the static drag force. Further, the potential impact of decorative crockets on these forces was of interest.

Both static and dynamic forces on pinnacles were investigated through a series of wind tunnel tests. The results demonstrate the relative magnitude of these forces, and that the decorative crockets do appreciably affect both the drag force and wind-induced vibration. The experimental data was used to derive general relationships for wind forces acting on stone pinnacles for potential use in engineering practice.

KEYWORDS: Wind, drag, vortex-induced vibration, pinnacles, historic masonry