Experimental Analysis of a Post-tensioned Timber Connection

The moment-rotation-behaviour of a post-tensioned beam-column timber joint has been analysed extensively with a series of static bending tests. The timber joint was loaded at the end of the beams in order to apply a moment to the connection. The tests were conducted with various forces in the tendon, from 300 kN up to 700 kN. The bending tests were performed with a controlled load level, so that no failure perpendicular to the grain in the column occurred.

The maximally allowable vertical load to be applied was estimated using a simple spring model. A final bending test was conducted in order to study the failure mode of the post-tensioned timber beam-column joint. The vertical load on the beams was increased until the tendon-elongation got so high that the test had to be stopped for safety reasons.

This paper presents the main results of bending tests on the post-tensioned timber joint. Attention will be given to the structural behaviour and to the influence of the applied post-tensioning force on the connection stiffness. The experimental results will be compared to the results obtained using a simplified analytical calculation model.