The residual load carrying capacity of timber joints

Abstract

Timber joints that have been preloaded for 2 to 8 years have been short term tested in accordance with EN 26891. The applied load levels varied between 30% and 50% of the average short term strength. The study comprised nailed, toothed-plate and split-ring joints. All joints were made of spruce and loaded in tension. The test results indicated no strength loss during this period. The strength of the preloaded joints was at least equal to the average short term strength of joints with no pre loading prior to testing. Actually, the results indicate a slight increase in strength. The development of the strength of the joints in time is modelled with an exponential damage equation. The parameters of the damage equations have been determined on the basis of time to failure tests on the same types of joints.Civil Engineering and Geoscience