Integrated approach to assess tree stability in storms and risk assessment
Academic Institution: University of Dundee
Academic Supervisor: Professor Matteo Oryem Ciantia
Industry Partner: Agroservice s.r.l
PhD Student: Andrea Marsiglia
Summary:
The project aims to address the safety and stability of urban trees, particularly in light of extreme weather events like Storm Arwen, which caused significant tree uprooting and widespread damage.
The study introduces a novel Dynamic Root Evaluation (DRE) technique for assessing the safety of trees using a mechanistic approach grounded in geotechnical engineering principles. This is a cheaper and more efficient alternative to traditional SIM (Static Integrate Method – Static Pull) tests, enabling the creation of hazard maps to guide public space management before strong winds.
This research focuses on evaluating the factor of safety (Fs) of urban trees by treating them as civil engineering structures. Traditional tree safety assessments rely heavily on subjective visual inspection, but this project proposes a more quantitative approach using the SIM and DRE methods. By applying a bending load on the trunk via cables and analysing wind loading data, the project has demonstrated that these methods can reliably calculate the factor of safety for trees.
Moreover, a machine-learning approach is proposed to enhance the correlation between geotechnical modelling and tree deflection measurements, contributing to predictive tools for urban tree safety assessments.
Key Results/Outcomes:
The DRE method has proven to be an efficient and low-cost alternative to SIM, requiring only a few hours of wind data to provide reliable safety factors.
Implementation of DRE allows for the development of hazard maps for urban trees, potentially informing decisions related to tree felling or public space closures in advance of extreme weather events.
Publications:
Galli, A., Sala, C., Castellanza, R., Marsiglia, A., & Ciantia, M. O. (2023). Lesson learnt from static pulling tests on trees: an experimental study on toppling behaviour of complex foundations. Acta Geotechnica. Advance online publication. https://doi.org/10.1007/s11440-023-02004-1
Galli, A., Marrazzo, G., Marsiglia, A., Ezzati, A., Ciantia, M. O., & Castellanza, R. (2023). Small Scale Toppling Tests on Simplified Tree Root Prototypes. In A. Ferrari, G. Gottardi, M. Ziccarelli, & M. Rosone (Eds.), Geotechnical Engineering in the Digital and Technological Innovation Era (1 ed., pp. 71-78). (Springer Series in Geomechanics and Geoengineering (SSGG)). Springer https://doi.org/10.1007/978-3-031-34761-0_9
Marsiglia, A., Galli, A., Marrazzo, G., Castellanza, R., & Ciantia, M. O. (2023). Uprooting Safety Factor of Trees from Static Pulling Tests and Dynamic Monitoring. In A. Ferrari, G. Gottardi, M. Ziccarelli, & M. Rosone (Eds.), Geotechnical Engineering in the Digital and Technological Innovation Era (1 ed., pp. 218-225). (Springer Series in Geomechanics and Geoengineering (SSGG)). Springer . https://doi.org/10.1007/978-3-031-34761-0_27
Marsiglia, A., Ciantia, M. O., Galli, A., & Canepa, D. (2022). Vertical loading tests on a simplified tree root prototype. In Physical Modelling in Geotechnics (pp. 832-835). (ICPMG 2022 Proceedings). Korean Geotechnical Society.
Contact Information
Dr Matteo Ciantia
Senior Lecturer of Soil Mechanics and Geotechnical Engineering, University of Dundee
Andrea Marsiglia
Post-Graduate Researcher, University of Dundee
2417420@dundee.ac.uk