Purlin Design

Design of Purlin

No :

Project :

Design by :

1.Geometry Data Simple Span Length Purlin Spacing ,S (@)

6.00 m. 0.70 m.

1.1 Material Properties Es Steel Modulus of Elastici Yield Strength Fy

### 2500

ksc. ksc.

Dead load ,DL Live load ,LL

204 159

Allowable Tensile StressFb=0.6Fy 1500 Allowable Shear Stress Fv=0.4Fy 1000

ksc. ksc.

Presure of Wind Load ,Pn Angle of Roof

414 Kg./m2 30.0 Deg.

Kg./m2 Kg./m2

2. Calculation Gravity Loads on Purlin 2.1 Summaries Load (DL+LL)xS = 254 Kg./m 2 = 2.2 Wind Load ,S.2Pn.sin/(1+sin ), Wd 231.8 Kg./m Wy = 254.1 cos30+Wd Wx = 254.1 sin30 Mx = Wy.L2/8

= 451.9 Kg./m = 127.0 Kg./m = 2033.4 Kg.-m

My = Wx.L2/8 Wx.L2/32

= 571.5 Kg.-m = Kg.-m ( For Design Sag Rod at Mid Span)

Required Sx = Mx/Fb

Vy = Vx =

= 135.6 cm3

3.Define Steel Member Use C 100x50x20x4.5

1

30

width, bf= depth, d =

5.0 cm 10.0 cm

moment of inertia, Ix = Iy =

139.0 cm4 30.9 cm4

thick of web, tw= thick of flange, tf=

0.45 cm 0.45 cm

section modulus, Sx = Sx =

27.7 cm3 9.8 cm3

section area, Ax =

9.47 cm2

radius of gyration, rx = weight , w =

3.8 cm 7.43 kg/m

4.Determine Tensile and Shearing Stress 4.1 fb= Mx/Sx + 2My/Sy = ### Kg./m 4.2 fv= Vx/Af + Vy/Aw = 537.53 Kg.

5.Deflection Check Allowable Deflection allow = L/360 Actural Deflecton max = WyL4/145.EIx ***

= =

al Force in Sag Rog = Sag Rod Length, Tiral Rod, RB Ax rx nsile Stress ,fa =P/Ax Check Slenderness K = 1.0 ,

1.67 cm. 13.84 cm.

Not OK

*** This Case not Consider *** 10 Vx = L = 15 = 1.77 = 0.38 = 2,157.0 ratio KL/rx =

### X mm. cm2 cm ksc. ###

So that, Sag Rod used need Sag Rod

Sx not OK

fv