Week 3 Challenge

S.No:1

Aim:To Calculate effective length factor of columns.

Introduction:Height of the column=10m.

a)Braced frame and shear wall

Effective length=1.2L

=1.2x10

=12m

b)unbraced frame with a pinned base

Effective length=1.0L

=1.0x10

=10m

c)unbraced frame with a fixed base

Effective length=2.0L

=2.0x10

=20m

S-No:2

Aim: To Calculate the Axial compressive capacity of Column made up of Hot rolled ISMB 300 with flange cover plate of 200x12 mm on each flange having length of beam as 3 m. Assume the bottom of the column is Fixed and Top as Roller (Rotation Fixed, translation free). Yield strength of material fy= 250 N/mm²

Explanation: As per IS800:2007 table-46

Area=56.26cm^2,depth of section=300mm,width of flange=140mm,thickness of flange=12.4mm,thickness of web=7.5mm,

area of plate=200x12

=2400mm

effective length=2.0L

=1.2x3000

=3600mm

Radius of Gyration=□">√I/A

Iyy=Iyy of ISMB300+Iyy of plate

=5680608.33+16000000

=21680608.33mm^4

Area=area of ISMB300+area of plate

=5536+4800

=10336mm^2.

Radius of gyration=45.8mm.

Slenderness Ratio=KL/r

=3600/45.8

=78.6

from table-9c we get 152.14N/mm^2

design strength=152.14x10336

=1572.51KN.

due to axial carring capacity=1048KN.

Result: Load carrying capacity=1048KN

S.No-3

Aim:To Design 2 m long tubular strut member to carry factored axial load of 400 kN. Assume the ends of the member are simply supported and the yield strength fy=210 Mpa. Also find Equivalent Square hollow sections.

Explanation: Let Fcd=80N/mm^2

Area=(400000/80)

=5000mm^2

dia=80mm.

From IS800:2007 table-2.

for cicular hollow=88ε^2

ε=√250/210

=1.09

=88x1.09^2

=104.76

hence D/t≤104.76

Assume D=80mm and t=8mm

80/8=10

hence approved

Slenderness ratio=KL/r r=80/2=40mm

=2000/40

=50

From table 9c 159MPa

design strength=159x5000

=795000N

Result:Design strength=795KN

S-No:4

Aim:To Design a single laced column made up of two channels back to back of 10 m height to carry factored axial load of 1000kN. The lacings are bolted. Design of bolted connection not required.

Explanation: Explanation is on file_09Aug22

Result: Requirement is satisfied

S-No:5

Aim: To Design a battened column made up of two channels back to back of 5 m height to carry factored axial load of 2000kN. The Battens are welded. Design of weld not required. Use Hot rolled channel sections.

Explanation: Explanation is on file_09Aug22-1

Result: hence ok