Obituary: Preben Hoffmeyer (1939–2018)
Preben was a graduate of the State University of New York, NY, USA, where he studied the effect of duration of load (DOL), moisture state, and moisture variation on the strength of timber during the period 1988–1990. In his thesis work, Preben initiated long-term mechanical experiments to investigate DOL behavior which ended up lasting 13 years and has been reported in several publications (Gustafsson et al. 1998; Hanhijärvi et al. 1998; Hoffmeyer 1990; Hoffmeyer and Sørensen 2007). This study generated enormous amounts of meticulously recorded, high-quality data. These experimental data are the foundation for the predictions of DOL behavior of structural timber components in the European building code, Eurocode 5: Design of timber structures, as they serve as calibration data for the theoretical prediction models. With his knowledge of DOL, Preben also contributed to several textbooks including “Timber Engineering STEP 1” edited by Blass et al. (Hoffmeyer 1995) and “Timber Engineering” by Thelandersson and Larsen (Hoffmeyer 2003). The successful outcome of Preben’s thesis work on DOL rested heavily upon skillful grading of the timber used into batches with very similar distribution in mechanical properties. Based on his experience on this topic, Preben was a leading contributor to writing the Nordic INSTA 142 standard for visual strength grading of timber. The guidelines for visual grading of timber are now adopted in the European standards. Another important contribution by Preben is the brilliant invention of the Pilodyn (patented in 8 countries, original Danish patent DK394375A from 1975) which was developed for detection of soft rot in Swedish utility poles in the 1970ies. Since then, the Pilodyn has been applied worldwide as a practical and efficient tool for evaluating the soundness of timber structures. It has even found use as a tool for underwater inspection of archeological wood.
For his research, Preben received several national and international distinctions. He was a Fellow of the International Academy of Wood Science (IAWS) since 1992, and Honorary Professor at the Royal Veterinary and Agricultural University (now part of the University of Copenhagen) since 2006.
As an experimental researcher, Preben was bright, thorough, and meticulous, a combination that made his results relevant and trustworthy. In professional interactions, he was the well-prepared gentleman, whose analysis of the situation at hand and whose idea for a possible solution more often than not was simply superior. Indeed, in hindsight, his elegant solutions often seemed to be so obvious that people around him forgot where they came from. As a colleague and friend, Preben was humorous and generous, and always good company. He will be dearly missed and remembered by those who are so fortunate as to have worked with him.
Preben leaves behind his wife, two daughters, and a son as well as four grandchildren.
Æret være Prebens minde.
- Hoffmeyer P (1990) Failure of wood as influenced by moisture and duration of load. Doctoral dissertation. College of Environmental Science and Forestry, State University of New York, Syracuse, NY, USAGoogle Scholar
- Hoffmeyer P (1995) A4 wood as a building material. In: Blass HJ, Aune P, Choo BS et al (eds) Timber engineering STEP 1. Centrum Hout, Almere, pp A4/1–A4/21Google Scholar
- Hoffmeyer P (2003) Strength under long-term loading. In: Thelandersson S, Larsen HJ (eds) Timber engineering. Wiley, Chicester, pp 131–152Google Scholar