This document discusses different types of roof trusses and the materials used to construct them. It describes king post trusses, howe trusses, pratt trusses, and fink trusses. Common materials used include various grades of structural steel for the chords, king posts, and gussets. Higher strength steels of 450 MPa yield strength are being used more frequently. Disadvantages of steel include maintenance costs, fireproofing requirements, and susceptibility to fatigue and brittle fracture. Case studies of different truss types provide details on materials like angle sections and plate thicknesses used.
2. TRUSS
Members of a typical bridge truss Members of a typical roof truss
MATERIALSβ in general we use structural steel or mild steel of various grades and different sections
The steel grades with yield strengths of
250 N/sq mm and 350 N/sq mm are
generally used for structural members.
The higher strength steel with yield
strength around 450 N/sq mm is now
being used more and more in the
construction.
DISADVANTAGES
*Maintenance cost
*Fire proofing cost
*Fatigue
*Brittle fracture
4. ROOFTRUSS
KING POSTTRUSS
King post truss at pedestrian bridge at Waria
railway station , west Bengal , India
MATERIALS
Top chords
Angle 90 (structural steel thickness β 6mm)
Bottom chord
Angle 90 (structural steel thickness β 10mm)
King post
Angle 90 (structural steel thickness β 10mm)
Metal gussets
Steel plate (structural steel thickness β 15mm)
5. ROOFTRUSS
HOWETRUSS
KALYAN INDUSTRIES, DURGAPUR , west
Bengal , India
MATERIALS
Top chords
Angle 90 (structural steel thickness β 6mm)
Bottom chord
Angle 90 (structural steel thickness β 10mm)
King post and truss web
Angle 90 (structural steel thickness β 10mm)
Metal gussets
Steel plate (structural steel thickness β 15mm)
6. ROOFTRUSS
PRATTTRUSS
DUTTA NISSAN FACTORY, DURGAPUR ,
west Bengal , India
MATERIALS
Top chords
Angle 90 (structural steel thickness β 6mm)
Bottom chord
Angle 90 (structural steel thickness β 10mm)
King post and truss web
Angle 90 (structural steel thickness β 10mm)
Metal gussets
Steel plate (structural steel thickness β 15mm)
7. ROOFTRUSS
FINKTRUSS
DURGAPUR STEEL PLANT β SECTION MILL
SITE , west Bengal , India
MATERIALS
Top chords
Angle 90 (structural steel thickness β 6mm)
Bottom chord
Angle 90 (structural steel thickness β 10mm)
Truss web
Angle 90 (structural steel thickness β 10mm)
8. STRUCTURAL STEEL
(THAT ARE USED IN CONSTRUCTION)
ANGLE 90
CROSSECTION
Legs β 90 mm
Thickness β 6mm
Unit weight β 8.2kg/m
CROSSECTION
Legs β 90 mm
Thickness β 8mm
Unit weight β 10.8kg/m
MEDIUM BEAMS
CROSSECTION
Width β 250 mm
Flange β 125mm
Web- 6.9mm
Unit weight -37.3kg/m
CROSSECTION
Width β 300 mm
Flange β 140mm
Web- 7.7mm
Unit weight -46kg/m
WIDE PARRAEL BEAMS
CROSSECTION
Width β148mm
Flange β 160mm
Web- 4.5mm
Unit weight -23.83kg/m
CROSSECTION
Width β 152 mm
Flange β 160mm
Web- 6mm
Unit weight -30.44kg/m
CROSSECTION
Width β 180 mm
Flange β 166mm
Web- 14mm
Unit weight -76.33kg/m
NARROW PARALLEL BEAMS
CROSSECTION
Width β 100 mm
Flange β 55mm
Web- 4.1mm
Unit weight -8.1kg/m
CROSSECTION
Width β 200 mm
Flange β 100mm
Web- 5.8mm
Unit weight -22.36kg/m
CROSSECTION
Width β 250 mm
Flange β 125mm
Web- 6mm
Unit weight -30.11kg/m
MEDIUM CHANNEL
CROSSECTION
Width β 300 mm
Flange β 90mm
Web- 7.3mm
Unit weight -36.3kg/m
9. CONCLUSION
THANK YOU
As we have studied steel roof truss and the material of it
WE CONCLUDE
Tension members and compression members of the
steel truss varies with respect to their load on it and the
sections are different which lowers the economy .