Roof Diaphragm Design Example

In figure 1 wind pressure on the walls parallel to length l act on the building.

Roof diaphragm design example.

Design example 2 n flexible diaphragm design diaphragm unit shear at the east side of line 3 and at line 9 is 136 000 160 850. The manual includes pertinent design information considerations fastener information deck shear capacity tables and a plethora of highly relevant design examples stepping you through all the. Shear nailing of the roof diaphragm north south the diaphragm loaded in the north south direction has been selected to illustrate the design of a wood structural panel roof diaphragm. The roof acting as a simple span horizontal girder of depth b distributes the wind line load as a shear reaction along the top of the end walls perpendicular to l.

The diaphragm resists the in plane loads by acting as a large horizontal beam spanning between the supporting end walls that are known as shear walls. The roof diaphragm design example can go up against different style that when nitty gritty right can ooze a cutting edge feel. Figure 1 illustrates the basic concept for a roof and wall diaphragm. The sdi diaphragm design manual third edition is an excellent design reference every engineer should utilize if designing with steel deck diaphragms.

At the roof level these wall reactions turn the load in the roof system in the plane of the roof. 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. 13 5 l x 16 9 x l 13 5 18 ft 16 9 6 ft 24 14 4 psf. And a width b 300 ft.

The roof deck is a wr wide rib type panel with a panel width of 36. Calculate the lateral load on the roof diaphragm. Now let s work on an example. A similar design is required in the other orthogonal direction east west.

A roof design gives the chance to extra floor space in the roof volume similar to a space or upper room space. The roof deck is supported by joists that are thick and spaced at 5 ft. A line load reaction of this pressure is distributed to the top of the wall at the roof plane via the vertical spanning capacity of the cladding over height h. Design a roof deck for a length of l 500 ft.

The roof diaphragm will take load from half the wall below and load directly applied to the diaphragm. First off the roof diaphragm design example is an extremely basic direct and utilitarian design every single current trademark. Lbs ft plf 2. Diaphragms and shear walls are used in the lateral design of a building the structural system is termed a box sys tem shear walls provide reactions for the roof and floor diaphragms and transmit the forces into the foundation.

Section 2305 general design requirements for lateral force resisting systems 2305 1 general.