Experimental testing of a rocking timber shear wall with slip-friction connectors



Allowing a structure to uplift and rock during an earthquake is one way in which activated forces can be capped and damage to the structure avoided or minimised. Slip-friction connectors (also known as slotted-bolt connectors) were originally developed for use in steel construction, but for this research have been adapted for use as hold-downs in an experimental 2.4 m × 2.4 m rigid timber shear wall. A novel approach is used to achieve the desired sliding threshold in the connectors, and the wall uplifts when this threshold is reached. From a series of quasi-static cyclic tests, it is shown that slip-friction connectors can impart ductile and elasto-plastic characteristics to what would otherwise be essentially brittle structures. Because forces on the wall were capped by the slip-friction connectors to levels well below the design level, no damage to the wall was observed. Self-centring potential was also found to be excellent. The slip-friction connectors themselves are of a unique design and have proven to be robust and durable, adequately performing their duty even after almost 14 m of cumulative travel under high contact pressures. To resist base shear without unduly affecting rocking behaviour, a new type of shear-key is proposed and implemented, and a procedure developed to quantify its influence on overall wall behaviour. Copyright © 2014 John Wiley & Sons, Ltd.