Anchor Bolts:

These are designed to resist the net uplift pressure acting on the roof truss. One end of the roof truss is fixed and is the fixed bearing. The other end which is the sliding bearing is provided with elliptical slots so as to allow some horizontal movement of the base plate, over the bearing surface.

Example

Design a four-panel Howe roof truss, as shown in Figure (a), of 10 m span and 2.5 m central rise. The roof carries ACC sheet covering. The wind pressure may be taken as 1.25 kN/m² of surface area normal to the roof. The spacing of trusses is 4 m center to center. The trusses are supported on 25 cm wide RCC columns

Figure

Solution

The slope of the roof truss is tan ^-1  1/2= 26.57^o

The sloping side of the truss is == 5.59 m

Assumed dead loads