Residual Clamping Force for Corroded Tension-Control Bolts

摘要

This study investigated the residual clamping force for corroded tension-control bolts and the effect of each part on force reduction. A finite-element analysis revealed that bolt head section loss, and in particular bolt head diameter reduction, does not reduce the clamping force as much as a decrease in nut width. The root sum square value of the reductions, which is converted into nut width reduction, is proposed as an indicator for estimating the residual clamping force for corroded tension-control bolts. To verify the validity of the proposed method, the residual clamping force of corroded bolts cut from actual steel bridges was measured. The experimental results showed that the accuracy of the proposed method was +/- 15%. (C) 2020 American Society of Civil Engineers.