roof design | truss design | different type truss design

Design of Roof Trusses * Roof trusses are supported on walls or a series of columns * Bracings In the end panel of roof level bracings are to be provided using ISA 9060, 8 mm. Diagonal bracings are provided in the last but one panel at bottom chord level. For very long buildings additional diagonal bracings are provided at every 4 to 5 days. * Members of Trusses 1. Top chord members 2. Bottom chord members 3. Struts: Compression members not belonging to top or bottom chords 4. Slings: Tension members not belonging to top or bottom chord. 5. Sag tie: Member subjected to zero forces but provided to reduce sag of bottom chord member. * Pitch of truss 1. Minimum pitch for GI sheeting = . 2. Minimum pitch for A.C. sheeting = . 3. Preferable pitches: , if snow load is expected , if snow is not expected * Spacing (a) 3 to 4.5 m upto 15 m span (b) 4.5 to 6.0 m for 15 to 30 m span (c) More than 40 m span, spacing of 12 to 15 m may be used with cross trusses replacing purlins. * Purlins 1. As fa...