Bending Strength of Members in Existing Wooden Check Dams

Construction of wooden check dams in Kyoto prefecture started in 1999, and over 130 wooden dams had been constructed as of 2013. However, these wooden check dams were constructed using members with no preservative treatment, and such members are inevitably subject to a decrease in strength due to deterioration over time. Therefore, in order to maintain wooden check dams, it is essential to evaluate the strength and durability of members in field inspections, to acquire data on secular changes in the strength of the members, and to develop techniques to estimate their strength. Accordingly, we conducted bending strength testing of members sampled from existing wooden check dams and measured them with Pilodyn and Resistograph tests. As a result, we found a negative correlation between the Pilodyn and Resistograph measurements and the bending strength. This result suggests that it will be possible to estimate the bending strength of the members in field inspections by using these techniques designed to measure the deterioration of the members. It was also found that members of wooden check dams tend to undergo deterioration faster at the dam wings or the crest of dam wings than at the dam bodies or the spillway crests, and that the rate of such deterioration varies depending on the wooden check dam.