Load Capacities of Single-Layer Shoring Systems: An Experimental Study

Abstract

This investigation elucidates the load capacities of wooden shores and adjustable steel tube shores that are commonly used in construction. A series of loading tests was performed based on actual setups used on construction sites. Research results reveal that the load capacity of an isolated wooden or an adjustable steel tube shore declines as its length increases, and the load capacity of adjustable steel tube shores greatly exceeds that of wooden shores of the same length in isolated and multi-post shoring systems. A wooden shore fails by buckling under compression load. The failure of an adjustable steel tube shore in tests is due to buckling when the shore length exceeds 3.96 m, and the failure will be resulted from damage of connecting tube lock if the shore length is less than 3.96 m. When the top block of the adjustable steel tube shore is a wooden stringer, the load capacity is remarkably less than when it is a steel block. Adjustable steel tube shores will be reduced in load capacity after reuses. The load capacity of an isolated shore is reduced when the shore is placed on an inclined base. Reinforcing an isolated wooden shore with horizontal wooden bars and iron wires increases its load capacity. However, when an isolated wooden shore is reinforced with lateral cable bracings, the load capacity is not affected. Inserting the woodblock under an isolated wooden shore on an inclined plane can increase the load capacity of the shore. The multi-post shoring system that is reinforced with horizontal bracings only slightly affects the total load capacity of the system studied in this paper.