Wind Shear Wall Roof Diaphragm

The diaphragm forces tend to be transferred to the vertical resisting elements.

Wind shear wall roof diaphragm.

Diaphragm and shear wall example given. When looking at the wind tributary to a diaphragm in order to calculate the shear wall capacities i normally resolve the wind forces to the roof and half the wall height single story four ext. Illustrated in figure 1 is a diaphragm with an lfrs consisting of structural walls and collector elements. In structural engineering a diaphragm is a structural element that transmits lateral loads to the vertical resisting elements of a structure such as shear walls or frames diaphragms are typically horizontal but can be sloped such as in a gable roof on a wood structure or concrete ramp in a parking garage.

The ibc irc wfcm and icc 600 all contain prescriptive requirements for fastening roof sheathing. Use apa sheathing tables in x305 peter von buelow university of michigan tcaup slide 19 of 28. The lateral force is transferred through the web of the diaphragm to the walls which act as supports for the diaphragm. Design roof diaphragm sheathing and shear walls on short side.

Walls for simplicity sake. Wind load diaphragm sheathing floor roof framing parallel to walls add blocking floor joist blocking. Because the wall on the left does not extend the full depth of the diaphragm collector elements are needed to collect the shear from the diaphragm and to transfer it. The term diaphragm is usually applied to roofs and floors.

Side wall carries load to roof diaphragm at top and to foundation at bottom roof horizontal diaphragm carries load to end walls end wall vertical diaphragm or shear wall carries load to foundation v lb per lin ft of diaphragm width w lb per lin ft of wall f t lb c vh h 2 wl 2b wind load lb per sq ft figure 1. Diaphragm and shear wall perimeters. The fastening requirements are those required to resist uplift forces from wind pressures and shear forces. This force is then applied to the shearwalls at the roof eave height.

Function as a diaphragm to transfer lateral loads to the building s shear walls. Unblocked diaphragm capacity capacities in sdpws are nominal values. A shear wall however is a vertical cantilevered diaphragm. These construction systems can be used when designing a building for lateral loads such as those generated by wind or earthquakes.

A diaphragm is a flat structural unit acting like a deep thin beam.