Wind Forces in Overgrown Rope Façades

Drag Coefficient Suggestion for Climbing Plants Based on Study Review

Authors

  • Kilian Arnold Lucerne University of Applied Sciences and Arts
  • Susanne Gosztonyi Lucerne University of Applied Sciences and ArtsLucerne University of Applied Sciences and Arts Engineering and Architecture
  • Andreas Luible Lucerne University of Applied Sciences and Arts Engineering and Architecture

DOI:

https://doi.org/10.7480/jfde.2021.2.4831

Keywords:

Green façades, wind forces , overgrown rope façades , drag coefficient , climbing plants , urban greenery, UHI , vertical green systems

Abstract

Modern cities face a climatic problem due to the high proportion of sealed surfaces that increase the urban heat island (UHI) effect. Green surfaces offer a way to mitigate the UHI effect, as they positively influence the thermal energy storage and air temperature. To support an increase of green surfaces in the limited resources of cities, vertical spaces, e.g. façades, must be exploited. A possible realisation of a vertical green system are overgrown rope façades. Overgrown rope façades have pre-fitted ropes in front of façades on which climbing plants can grow. However, such systems have to deal with dynamic wind forces, which pose static challenges to the climbing system. In order to design such systems for the effective wind forces, so-called drag coefficients of the climbing plants must be known. Unfortunately, there are no guidelines or known values that provide such specific drag coefficients for climbing plants. In this study, based on a study review of relevant data for drag coefficients on deciduous and coniferous trees and leaves, findings are made comparable by applying the power function. Six critical factors to be considered are identified and a drag coefficient for climbing plants is derived from the investigations on deciduous trees. Their transferability to overgrown rope façades is analysed and discussed.

Author Biographies

Susanne Gosztonyi, Lucerne University of Applied Sciences and ArtsLucerne University of Applied Sciences and Arts Engineering and Architecture

Lucerne University of Applied Sciences and Arts Engineering and Architecture, lecturer

Andreas Luible, Lucerne University of Applied Sciences and Arts Engineering and Architecture

Lucerne University of Applied Sciences and Arts Engineering and Architecture, lecturer

References

Alexandri, E. & Jones, P. (2008). Temperature decreases in an urban canyon due to green walls and green roofs in diverseclimates. Building and Environment, 43(4), 480–493. doi: 10.1016/j.buildenv.2006.10.055

Djedjig, R., Bozonnet, E., & Belarbi, R. (2015). Experimental study of the urban microclimate mitigation potential of green roofs and green walls in street canyons. International Journal of Low-Carbon Technologies, 10(1), 34–44. doi: 10.1093/ijlct/ctt019

EN 1991-1-4. (2010). Eurocode 1: Actions on structures - Part 1-4: General actions - Wind actions. [Standard].

FLL. (2018). Fassadenbegrünungsrichtlinien-Richtlinie für die Planung, Ausführung und Pflege von Wand- und Fassadenbegrünungen [Façade greening guidelines - Guideline for the planning, execution and maintenance of wall and façade greenings]. [Guideline]. Bonn.

Gartland, L. M. (2012). Heat Islands: Understanding and Mitigating Heat in Urban Areas. Routledge. doi: 10.4324/9781849771559

Kane, B., Pavlis, M., Harris, J. R., & Seiler, J. (2008). Crown reconfiguration and trunk stress in deciduous trees. Canadian Journal of Forest Research, 38, 1275–1289. doi: 10.1139/X07-225

Kane, B. & Smiley, E. T. (2006). Drag coefficients and crown area estimation of red maple. Canadian Journal of Forest Research, 36(8), 1951–1958. doi: 10.1139/x06-086

Koizumi, A., Motoyama, J., Sawata, K., Sasaki, Y., & Hirai, T. (2010). Evaluation of drag coefficients of poplar-tree crowns by a field test method. Journal of Wood Science, 56(3), 189–193. doi: 10.1007/s10086-009-1091-8

Kolokotsa, D., Santamouris, M., & Zerefos, S. C. (2013). Green and cool roofs’ urban heat island mitigation potential in European climates for office buildings under free floating conditions. Solar Energy, 95, 118–130. doi: 10.1016/j.solener.2013.06.001

Leal Filho, W., Echevarria Icaza, L., Emanche, V. O., & Quasem Al-Amin, A. (2017). An Evidence-Based Review of Impacts, Strategies and Tools to Mitigate Urban Heat Islands. International Journal of Environmental Research and Public Health, 14(12). doi:10.3390/ijerph14121600

Mayhead, G. J. (1973). Some drag coefficients for british forest trees derived from wind tunnel studies. Agricultural Meteorology, 12,123–130. doi: 10.1016/0002-1571(73)90013-7

Meskouris, K., Butenweg, C., Hake, E., & Holler, S. (2012). Baustatik in Beispielen (2nd ed.) [Structural analysis in examples]. Berlin Heidelberg: Springer-Verlag. doi: 10.1007/978-3-642-23530-6

Mohajerani, A., Bakaric, J., Jeffrey-Bailey, T., & Mohajerani, A. (2018). The Urban Heat Island Effect, its Causes, and Mitigation, with Reference to the Thermal Properties of Asphalt Concrete. Journal of Environmental Management, 197, 522–538. doi:10.1016/j. jenvman.2017.03.095

Pfoser, N. (2016). Fassade und Pflanze. Potenziale einer neuen Fassadengestaltung

[Façade and plant. Potentials of a new façade design]. [Dissertation]. Technische Universität Darmstadt, https://tuprints.ulb.tu-darmstadt.de/id/eprint/5587

Pfoser, N. (2018). Vertikale Begrünung [Vertical greening]. Stuttgart: Verlag Eugen Ulmer. ISBN 978-3-8186-0088-4

Rudnicki, M., Mitchell, S. J., & Novak, M. D. (2004). Wind tunnel measurements of crown streamlining and drag relationships forthree conifer species. Canadian Journal of Forest Research, 34(3), 666–676. doi: 10.1139/x03-233

Santamouris, M., Papanikolaou, N., Livada, I., Koronakis, I., Georgakis, C., Argiriou, A., & Assimakopoulos, D. N. (2001). On the impactof urban climate on the energy consumption of buildings. Solar Energy, 70(3), 201–216. doi: 10.1016/S0038-092X(00)00095-5

SIA 261. (2014). Einwirkungen auf Tragwerke [Actions on supporting structures]. [Standard]. Switzerland

Vogel, S. (1984). Drag and Flexibility in Sessile Organisms. American Zoologist, 24(1), 37–44. JSTOR. doi: 10.1093/icb/24.1.37

Vogel, S. (1989). Drag and Reconfiguration of Broad Leaves in High Winds. Journal of Experimental Botany, 40(8), 941–948. doi:10.1093/jxb/40.8.941

Vollsinger, S., Mitchell, S., Byrne, K., Novak, M., & Rudnicki, M. (2005). Wind tunnel measurements of crown streamlining and drag relationships for several hardwood species. Canadian Journal of Forest Research, 35, 1238–1249. doi: 10.1139/x05-051

Downloads

Published

2021-07-01

How to Cite

Arnold, K., Gosztonyi, S., & Luible, A. (2021). Wind Forces in Overgrown Rope Façades: Drag Coefficient Suggestion for Climbing Plants Based on Study Review . Journal of Facade Design and Engineering, 9(2), 73–94. https://doi.org/10.7480/jfde.2021.2.4831