Experimental development, tradeoff analysis and design implementation of high force-to-volume damping technology
DOI:
https://doi.org/10.5459/bnzsee.40.2.35-48Abstract
Supplemental dampers are a means of repeatedly dissipating energy without damage to the underlying structure, increasing life-safety and helping provide better serviceability of structures following a major earthquake. High performance (small size) lead dampers are designed and tested to characterise their force-displacement behaviour and produce trade-off curves relating device geometry to force capacity, to parameterise the design space to enable further devices to be designed for structural applications. Peak forces of 120-350 kN were obtained for devices that were all able to fit within standard structural connections.
Results show that prestressing the working material is critical to obtain optimal energy dissipation. Although previously characterised as extrusion dampers it is shown that classical extrusion modelling formulations do not strictly work well for this class of damper. Instead a coulomb type of stress-based model is proposed, with relationships presented that are independent of device scale. Empirical reduction factor equations are applied to the New Zealand Structural Design Actions to enable lead extrusion devices to be incorporated into structural design analyses. The overall results indicate that repeatable, optimal energy dissipation can be obtained in a compact device to minimise damage to critical buildings and infrastructure.
References
Robinson, W.H. and Greenbank, L.R., (1976). “An extrusion energy absorber suitable for the protection of structures during an earthquake”. Earthquake Engineering and Structural Dynamics, 4(3):251-259. DOI: https://doi.org/10.1002/eqe.4290040306
Robinson, W.H. and Greenbank, L.R., (1975). “Properties of an extrusion energy absorber”. Bulletin of the New Zealand National Society for Earthquake Engineering, 8(3):187-191.
Cousins, W. J. and Porritt, T. E. (1993). "Improvements to lead-extrusion damper technology," Bulletin of the New Zealand National Society for Earthquake Engineering, vol. 26, pp. 342-348.
Rodgers, GW, Denmead, C, Leach, N, Chase, JG, Mander, JB. (2006). “Spectral evaluation of high force-volume lead dampers for structural response reduction,” Proc. New Zealand Society for Earthquake Engineering Annual Conference, Napier, New Zealand, March 10-12.
Skinner, R.I., Robinson, W.H. and McVerry, G.H., (1993). “An Introduction to Seismic Isolation”. John Wiley & Sons, Chichester.
Pearsons, C. E. and Parkins, R. N. (1960). "The Extrusion of Metals," 2nd Edition Revised, London: Chapman & Hall Ltd, pp. 201-221.
Pekcan, G, Mander, J.B, and Chen, S.S. (1999). "Fundamental Considerations for the Design of Non-linear Viscous Dampers," Earthquake Engineering and Structural Dynamics, vol. 28, pp. 1405-1425.
Standards New Zealand – Technical Committee BD-006-04, “NZS 1170.5 Supp 1:2004: Structural Design Actions – Part 5: Earthquake Actions – New Zealand – Commentary”; Standards New Zealand, Wellington, New Zealand, 2004, Section C3.1, pp 17-28.
Solberg, KM, Bradley, BA, Rodgers, GW, Mander, JB, Dhakal, RP, and Chase, JG, (2007). “Multi-Level Seismic Performance Assessment of a Damage-protected Beam-column Joint with Internal Lead Dampers” Proc. New Zealand Society for Earthquake Engineering Annual Conference, Palmerston North, New Zealand, March 30-April 1.
