The objective of this research is to recommend a rational design method for bridge anchor bolt connections used by the Washington State Department of Transportation (WSDOT). An experimental investigation of the behavior of 3/4 inch diameter and 1-1/2 inch diameter, A449 canister/grout anchor bolts under various loading conditions was conducted. Shear loads were applied to anchor bolts subjected to various eccentricities, and the results obtained were used to develop tension/shear interaction relationships.
Elliptical tension/shear interaction relationships provided the best fit to the test data. However, closed-form solutions using tri-linear tension/shear interactions could be conservatively used by bridge designers at WSDOT. To verify the tension/shear interaction relationships, tests were performed on half-scale multiple anchor bolt connections, consisting of two anchor bolts parallel to the applied shear load. The strengths indicated by the multiple anchor bolt tests were conservative when compared to the results obtained from the testing program.
It has also been determined that the AISC/LRFD tension stress limits for bearing type connections could be used for designing WSDOT anchor bolt connections with A449 1-1/2 inch diameter bolts.