Repair of Timber Piles Using Ultra-High-Performance Concrete: Investigation of Load Transfer and Load-Carrying Capacity

Abstract

Timber piles have been used for a long time in bridges and marine structures. Many of these structures have exceeded their service life and require maintenance or repair because of deterioration. To address this issue, repair/retrofit techniques utilizing ultra-high-performance concrete (UHPC) can provide many advantages, such as minimizing repair material amounts and high durability because of its superior mechanical characteristics. This paper presents preliminary tests to comprehend the behavior of composite specimens made of timber and UHPC, including the load transfer mechanism and load-carrying capacity. For load transfer between the timber pile and UHPC, push-off and slant shear tests were conducted on composite timber and UHPC specimens with different surface preparations for timber surfaces. It was concluded that because of the smoothness of the UHPC surface, mechanical connectors (nails) provided the highest interface shear strength between timber and UHPC. For the load-carrying capacity, several specimens were tested under compression loading and it was concluded that timber treatment before casting UHPC plays a vital role in restoring the load-carrying capacity of timber piles.