Civil Engineering Association

Seismic Response of Telescopic Pipe Pin Connections

Two-way hinges are often used in reinforced concrete bridge columns to prevent excessive flexural stresses from entering the connection to the superstructure or the footing. A study was undertaken for Caltrans to understand the behavior of pipe pin connections to help develop a simple and reliable design method. Two 0.3 scale specimens were constructed and tested under cyclic loading to determine if the models behave in pure shear and to study the effect of rotation on the connection behavior and strength. Analytical studies of a simple method gave the foundation for the development of a design method. A sensitivity analysis of the equations revealed that using the ultimate stress of the pipe (rather than the yield stress) in calculations leads to a close estimate of the actual ultimate connection capacity. If yielding is to be avoided in the pin, however, the pipe yield stress should be used in the simple method.