Roof Diaphragm Design

The roof diaphragm is designed to transfer shear forces from the loaded side of the building into the shearwalls run ning parallel to direction of the load.

Roof diaphragm design.

Each of these different deck types are described in the steel deck institute sdi publication no 31 design manual for composite decks form decks and roof decks. The diaphragm can be thought of as a horizontal beam or as a plate element. Main features roof diaphragm design example first off the roof diaphragm design example is an extremely basic direct and utilitarian design every single current trademark. It is usually constructed of wood sheathing steel deck or concrete.

Steel roof and floor deck diaphragm design requires careful attention to load paths stiffness variations fastener types and regional preferences figure 1. Due to failures of some roof diaphragms. Download profis df diaphragm now. 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.

A horizontal timber or metal resting at the peak of the roof the rafters and trusses are connected to the ridge board for a cohesive framework. The 2018 international building code ibc specifies that structures using wood framed shear walls and diaphragms to resist wind seismic and other lateral loads shall be designed and constructed in accordance with awc s 2015 special design provisions for wind and seismic sdpws or2018 wood frame construction manual wfcm for one and two family dwellings. Just as the floor or roof is checked for vertical load capacity it is considered a diaphragm in the plane of the floor and check for shear when designing the lateral force resisting system. Roof diaphragms may be assembled from a wide variety of panel profiles including narrow rib nr intermediate rib ir and wide rib wr.

Structures using wood frame shear walls or wood frame diaphragms to resist wind seismic or other lateral loads shall be designed and constructed in accordance with af pa sdpws and the applicable provisions of sections 2305 2306 and 2307. Section 2305 general design requirements for lateral force resisting systems 2305 1 general. A composite decking made of solid materials it resembles real wood and particularly strong and stable for bearing heavy load. Shear diaphragms are commonly used in buildings as a means of transmitting lateral loads.

Hilti profis df diaphragm software is designed to help select the optimum hilti fastening solutions for your decking project. In its most basic form a diaphragm behaves as if it were a short deep beam. 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 roof diaphragm is not designed to resist the lateral forces generated in the build ing that act to pull opposite walls away from each other.