structural design of purlin
TRANSCRIPT
-
8/11/2019 Structural Design of Purlin
1/3
-
8/11/2019 Structural Design of Purlin
2/3
Thus required Section with Zx= 53.09 cm 3
Requird Zy= 8.848 cm 3
I section Satisfying above 2 creteria is ISMB 125Zxx = 71.8 cm 3
Zyy = 11.7 cm3
Ixx = 449 cm 4
Iyy = 43.7 cm 4
Chk for Actual Stresses Mdlx/Zxx+Mdly/ZyyCase-1
122.3446 < 165 N/mm2 Ok
Case-2 30.31937 < 165 N/mm2 Ok
Deflection ChkCase-1 Allowab(L/250)dx = (5*W*L^4)/(384*E*Ixx) 27.78 mm > 20 mm UnsafeUse ISMB 150Ixx = 726.4 cm 4 17.17 mm < 20 mm OK
Iyy = 52.6 cm4
dy = (5*W*L^4)/(384*E*Iyy) 5.656 mm < 20 mm OK
Case-2
dx = (5*W*L^4)/(384*E*Ixx) -2.365 mm < 20 mm OK
dy = (5*W*L^4)/(384*E*Iyy) 5.656 mm < 20 mm OK
Use ISMB 150 as Purline Over Roof Self Weight= 14.9 kg/mTotal No. 7 of 20.0m longTotal Weight 2.086 Mt
-
8/11/2019 Structural Design of Purlin
3/3
Spacing of purlin @2000c/c = 2 m
For Sheetingmm
0 Kg/m 2
0 Kg/m 2
0 Kg/m 2
0 Kg/m20 Kg/m20 Kg/m2
Sheeting 0.5mm thk 3.925 Kg/m23.925 Kg/m2
Assuming total dead load = 3.92500 Kg/m2
Live load on roof = 75 Kg/m 2
Dust Load = 0 Kg/m 2
Hung Load = 0 Kg/m 2
Total load on roof= 78.925 Kg/m 2
Load on PurlinDead load= 3.925 Kg/m 2 = 0.079 Kn/mLive load= 75.00 Kg/m 2 = 1.500 Kn/mSelf Weight = 0.616 Kn/m ISMB400Wind Load from Load Claculation SheetCase-3 (Away)= 1.31 Kn/m 2 = 2.62 Kn/m
Load Calculation for Purlin
Dead Load Average thickness of slab
Selfweight @2500Kg/m 3)
Total
12mm thk Plaster over Foam Concrete and RCC slab
30mm thick Polyurethane foam @ 45Kg/m 3)50mm thk foam Conc. @ 500kg/m 3
20 thk tiles @2100 Kg/m 3
Metal Deck (1mm) @15 Kg/m 2