Cyclic tests of a precast restrained rocking system for sustainable and resilient seismic design of bridges

• Cyclic tests of rocking columns restrained with a tendon-spring system are presented. The spring was designed so that the exhibits negative post uplift stiffness. One column's ends were protected by steel jackets while other one discs. two tested to 15% and 30% drift exhibited no damage. column reduces design moments on foundation. Letting sustain motion has been suggested as seismic method for bridges. In an effort increase redundancy bridge, most researchers use ungrouted restraining tendons passing through columns. However, it argued these unnecessarily forces superstructure foundation, systems should be unrestrained. combine benefits both approaches this paper suggests flexible comprising tendon in series disc springs, essentially forming isolation precast structures. It presents cyclic 1:5 scale RC either or able drifts more than (and some cases 30%) without any significant damage – hence they resilient. behavior springs is well predicted analytical models. strength (i.e. force) stiffness can reasonable accuracy using rigid body model. model does not predict pre-uplift behavior. As anchored within column, moment foundation drastically decreases, therefore costly material intensive pile foundations could avoided concept contributes sustainability.