For wood/wood inclined screw connections, the threads of the screws are anchored into the side member and main member, so no pre-tensioning force is assumed in the screws. For steel/wood connections, the threads are not anchored to the steel plate. Instead, the axial resistance is generated through the head of the screw bearing upon the steel plate or wedge washer. This arrangement introduces a clamping effect since the screws can develop a pre-tension force during installation. Since the screws are loaded primarily in tension in service of design loads, even load-sharing is promoted through even pre-tensioning. This can be accomplished through the use of torque-clutch power tools. The torsional strength of Assy VG screws can be found in the Structural Screw Design Guides.
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