Roof Diaphragm Deflection

W 612 plf.

Roof diaphragm deflection.

If framing members are spaced more than 24 o c testing indicates further deflection increase of about 20 or 3 times the deflection of a comparable blocked diaphragm. To analyze the deflection of diaphragms bending shear and slip must be accounted for. What is the deflection equation for open front cantilever diaphragms. What are the available methods of distributing torsional forces into the diaphragm.

Calculate the lateral load on the roof diaphragm. There will also be slip. A shear wall however is a vertical cantilevered diaphragm. D 56 uniform load.

A diaphragm structure results when a series of such vertical and horizontal diaphragms are properly tied together to form a structural unit. The deck will have deflection similar to typical beam deflection. 1 1 2 x 18 ga deck vercor. The maximum roof diaphragm moment m equals ww wl x l2 8.

Also because the diaphragm beam is deep relative to its span it will also have shear deflection. Do shear walls located along diaphragm chord lines affect the diaphragm. Deflection of unblocked diaphragms is 2 5 times the deflection of blocked diaphragm. 9 0 purlin spacing w14x26 af 2 1 sqin 7 welds per sheet vsc 12.

L 42 diaphragm depth. Diaphragms and shear walls. The roof diaphragm will take load from half the wall below and load directly applied to the diaphragm. How is diaphragm flexibility defined for open front cantilever diaphragms vs.

The term diaphragm is usually applied to roofs and floors. This is based on limited testing of the diaphragm by apa. The thoracic diaphragm or simply the diaphragm ancient greek. However sdpws provides an option to calculate deflections using other methods such as the four term equations.

What is the total diaphragm deflection. The sdpws three term deflection equations are an algebraic simplification of the four term equations in the ibc. Asce 7 16 figure 12 3 1. The maximum unit shear on the wall diaphragm is also equal to the roof reaction r divided by b.

I could use some help on a calculation done for flexible diaphragm deflection. R 1 3 diaphragm span. Sheathing materials and unblocked wood structural panel diaphragms. A diaphragm is a flat structural unit acting like a deep thin beam.

The corresponding diaphragm chord forces are therefore equal to m divided by the diaphragm depth b. 13 5 l x 16 9 x l 13 5 18 ft 16 9 6 ft 24 14 4 psf.