Shear force causes adjacent materials to want to slide or slip past one another. In a wood member, horizontal shear (A) acts parallel to the wood grain, while vertical shear (B) acts across the grain. The movement of a member with respect to a fastener may also be the result of shear force (C). Shear also describes the movement of two members with respect to their original positions, as in the example of a bolted truss web member pulling away from the top chord (D).
Shear force causes adjacent materials to want to slide or slip past one another. In a wood member, horizontal shear (A) acts parallel to the wood grain, while vertical shear (B) acts across the grain. The movement of a member with respect to a fastener may also be the result of shear force (C). Shear also describes the movement of two members with respect to their original positions, as in the example of a bolted truss web member pulling away from the top chord (D).

Have you ever looked over an engineer’s structural calculations and felt like they were written in a foreign language? The purpose of this article is to try to make a little sense of the terms and symbols engineers use.

This is a way of describing a force acting at a distance. A teeter-totter is a good example (see Figure 1). Let’s assume that the seats are 14 feet apart and the hinge point is fixed at the middle of the board, 7 feet from each seat. You (the 160-pound adult) put your child (40 pounds) on the seat that is resting in the gravel, then walk to the...

or Register to continue reading