Pull-out strength of the glued-in joint in laminated bamboo structure

Abstract

The glued-in joint has proven its reliability, practicality, and flexibility in timber and concrete structures since first proposed. To study the pull-out strength of the glued-in joint in laminated bamboo structure, 27 specimens in pull-pull configuration were conducted. The influence of parameters, i.e., edge distance of the rebar, glue thickness, rebar diameter, anchorage length, were all tested by monotonic pull-out tests parallel to the grain. Three failure modes were characterized by the experimental results, referring to the splitting of laminated bamboo block, pull-out, and failure of rebar after yielding. Concluded from the experimental results, it is found that the first failure mode could be avoided by restricting the edge distance of the rebar in a reasonable range. The initial stiffness and load-carrying capacity of the latter two failure modes were recognized to be estimated in terms of the rebar diameter and anchorage length. Based on the existed theory, the feasibility of the traditional method was discussed and a simplified formula was developed based on the experimental results and theoretical derivation, which showed that the deviation is less than 6%. Finally, recommendations were made for the design of glued-in joint in the laminated bamboo structure.