Verification of raker shores using New Zealand timber

This paper investigates the capacity of full triangle (fixed) raker shores using New Zealand Timber, through analytical analyses and experimental tests. Full triangle (fixed) raker shores, or simply raker shores, are a temporary structure used to support collapsed or damaged buildings. They are used extensively by Urban Search and Rescue (USAR) teams around the world to allow the safe location and rescue of victims of collapsed or damaged buildings following an earthquake event. The shores used by New Zealand USAR are similar to those used in the United States; however they are made from Radiata Pine which has different mechanical properties than the timber used in the U.S. Hence, the need to verify the shores constructed in New Zealand still provide the required design strength. The analytical verification suggests that raker shores are unsafe, according to the New Zealand Timber Structures Standard NZS 3603:1993. However, the experimental results on full-scale specimens indicate that the performance of the raker shores satisfies the required demands, with a safety factor of 2 with regard to the design load, and a ductile type of failure. Suggestions to increase the capacity of the shores are also included.