Alternative timber to natural forest teak for shipbuilding

Background and Objective

As a result of the overexploitation of teak in its natural distribution area Indochina (India, Sri Lanka, Myanmar, Thailand, Laos, Vietnam and Cambodia), the availability of natural resources has decreased considerably. Only in Myanmar (Burma) major resources are currently available. The trade of "Burma teak", which fulfils the EUTR guidelines/obligations, is however difficult or currently not possible, as the required documents of legal origin cannot be accepted "without doubt". Based on this current (market) situation, the BMEL instructed the Thünen Institute to evaluate alternative timbers. Recherches have shown that tropical timber, e.g. Afzelia, Iroko and Itaubá, have comparable physical-mechanical properties as well as a high natural durability which correspond to the requirements for high-quality deckings. Compared to natural forest teak, no or only limited long-term experience in the utilisation as ship decking (working deck) are available for the selected timber. In this context, the properties of the alternative timber are being tested on an experimental facility (upper deck of the Gorch Fock).

Target Group

Shipbuilding (Wood industry) and science (property testing of alternative timber)

Approach

For a comparative testing of the suitability of the alternative timbers, in particular as a high-quality deck on the sailing ship Gorch Fock, the following characteristics (properties) have to be tested partly in the laboratory, partly in practical use (test area on the upper deck of the Gorch Fock):

• Moisture absorption and release (incl. speed) under changing climatic conditions
• Dimensional stability (deformation behaviour during moisture changes as a function of anatomical direction / relation tangential to radial)
• Surface treatment and quality (cracking, leaching of wood components, UV stability and absorption of treatment agents).
• Abrasion resistance and slip behaviour
• Machinability for repairs

Accompanying to the monitoring of the alternative timbers on the test area (Achterback) of the Gorch Fock, laboratory analyses for the evaluation of the hygroscopic behaviour (shrinkage, swelling and sorption tests) are carried out at the Thünen Institute of Wood Research in order to obtain comparative values to natural forest teak.

Our Research Questions

Testing of the suitability of alternative timber (Afzelia, Iroko and Itaubá) under real operating conditions in shipbuilding (especially for a working deck)