Explanation:

Truss is a pictophonetic character, wood is a shape, and behavior sounds. Truss is a crossbar on a beam or door frame, window frame, etc. ?

Example:

1, house truss, house crossbar also. -"Jade"

2. Trusses overlap. -Selected Works of Cao Shenfu. Note: "Truss, what is imposed on the beam."

3, all of wood truss, a long time. -"etiquette"