Experimental and analytical investigation of bridge timber piles under eccentric loads

This paper examines the structural behavior of bridge timber piles under eccentric compression loading. Samples of the piles were retrieved from a recently collapsed bridge and experimentally tested under compression and combined compression and flexure. The experimental timber pile response was used to calibrate a numerical model of full timber piles of a prototype bridge, including material and geometric nonlinearity as well as soil-structure interaction. The numerical results illustrated that the pile strength was significantly reduced under eccentric load compared to concentric load. Therefore, it was concluded that the effect of compression-flexure interaction on bridge timber piles must be checked during bridge design and/or rating, especially in the case of simply supported superstructures where loading on one span may lead to eccentric loading on a timber pile group.