124361160-Truss-Design.xls

Design of Roof Truss

Span of the Truss

=

39.00

m

Spacing of the Truss

=

6.10

m

Weight of roofing material

=

2.00

Kg / m 2

Miscellaneous loads

=

3.50

Kg / m 2

sloping angle of Truss

=

Sloping length of Truss

=

8.30

m

No. of Purlines

=

6

Nos

No of Pannels

=

6

Nos

Wind pressure

=

200

Kg / m 2

=

2 x 6.1

=

12.2

4

o

Dead Loads : b) Weight of Roof Material

d) Miscellaneous loads

= =

Total dead loads

=

Kg / m

3.5 x 6.1 21.4

Kg / m

33.55

Kg / m

Live Load

: = =

Total live load

= =

75 - 2 x ( 4 - 10 ) Kg / m 2

87.00

87 x ( (2/3)) x 6.1 353.80

Kg / m

Design of Principal Rafter : Maximum force =

179.54

Allowable Compressive stress = Area requried =

Kn N / mm 2

80.00

179.54 x 1000 80.00

=

2244.25

mm 2

As per IS 1161:1998 of Table - 1 Provide 150mm dia. Medium weight Tubular section ( Nominal Bore ) Sectonal properties of the Section Area

=

2420.00

cm 2

Modulus of Section

=

94.16

cm 2

Radious of Gyration

=

5.67

cm

Thickness of tube

=

4.80

cm

14.75

cm

Effextive length of the member =

The effective length of the member =

0.85 x 14.75 =

Slenderness ration of tube member =

=

41.79

< 180

Hence safe

12.54 1253.75 30

cm

Design of Tie member : Maximum force =

176.95

Kn

Allowable Compressive stress = Area requried =

125.00

N / mm 2

176.95 x 1000 125.00

=

1415.6

mm 2

As per IS 1161:1998 of Table - 1 Provide 150mm dia. Medium weight Tubular section ( Nominal Bore )

Design of Purline : ( As per Code IS: 806 - 1968 cl:6.5.4.1) Spacing of Purline

=

b) Weight of Roof Material

1.475

m

=

2 x 1.475

=

2.95

Kg / m

Self weight of Purline

=

#REF!

Kg / m

Total dead load

=

#REF!

Kg / m

Total live load

=

87 x 1.475

=

128.325

Kg / m

=

#REF!

Kg / m

Total load ( DL + LL ) Section modulus =

WL / 19840

Where W

=

Length of the Purline

=

=

=

#REF! 19840 5000.00 mm

#REF! 19840 #REF!

cm 3

As per IS 1161:1998 of Table - 1 Provide 80mm dia. Light weight Tubular section ( Nominal Bore )

Design of Roof Truss

Span of the Truss

=

39.00

m

Spacing of the Truss

=

6.10

m

Weight of roofing material

=

2.00

Kg / m 2

Miscellaneous loads

=

3.50

Kg / m 2

Self weight of Purline

=

13.00

Kg / m

sloping angle of Truss

=

Sloping length of Truss

=

8.30

m

No. of Purlines

=

6

Nos

No of Pannels

=

6

Nos

Self weight of Truss

=

(L/3) + 5

=

( 39 / 3 ) + 5

=

4

18.00

o

Kg / m 2

Dead Loads : a) Self weight of Roof Truss

= =

b) Weight of Roof Material

=

c) Weight of Purlines

d) Miscellaneous loads

4282.2

202.5

=

6 x 13 x 6.1

=

475.8

=

=

Kg

Kg

3.5 x 39 x 6.1 832.7

Kg

5793.17

Kg

Load acting on one intermediate pannel point =

=

Kg

2 x 8.3 x 6.1 x 2

=

= Total dead loads

(L/3) + 5 x 39 x 6.1

965.53

5793.17 6 Kg

Say

970.00

Kg

Live Load

: = =

Total live load

75 - 2 x ( 4 - 10 ) 87.00

Kg / m 2

=

87 x ( (2/3)) x 39 x 6.1

=

13798.20

Kg

Load acting on one intermediate pannel point =

= Say

2299.70

Kg

104.00

Kg

Total load acting on one intermediate pallel pont = Say

13798.20 6

3265.23

3270.00

Kg

Or Say 2.40 KN Wind load

:

Total wind load =

1.5 6.1 x 8.3 x 1.5 =

=

Kn / m 2 75.945 3.0

Kn

25.315

Kn

Kg