Bolt-Layout-Influence Study on Tensile Performance of Glulam Timber Bolted Connection with Slotted Steel Plate

Abstract:

This paper introduces a novel node connection method in wooden structures known as the multi-bolt steel insert plate connection. It categorizes specimens into 12 groups， each containing six specimens， for tensile testing， with four influencing factors， i.e.， bolt number， arrangement， bolt diameter， and base material thickness considered. The parameters obtained include failure modes， initial stiffness， yield load， peak load， and ductility coefficient. The test results reveal that， under the same conditions of consistent wood thickness and bolt diameter， damage occurrence increases with the number of bolts， and the failure mode exhibits a similar pattern. Splitting cracks of different degrees emerge on the left and right sides of the wood， extending from the top to below the last row of bolts. In terms of mechanical properties， an increase in the number of bolts corresponds to higher initial stiffness， yield load， and peak load， accompanied by a decrease in ductility. Ultimately， formulas for the initial stiffness and peak load of multi-bolt steel insert plate connection nodes are derived， utilizing bolt diameter and quantity as independent variables. These formulas align closely with the experimental data， validating their accuracy.

Key words:glulam timber;tensile connection;bolt layout;experimental study;fitted formula