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Content :
1 Structural Fasteners 
2 Tension member 
3 Compression member 
4 Beams 
5 Plate Girders
6 Industrial Roofs 
7 Plastic Analsis

marks weightage
IES - 20 to 22 objective
          40 to 50 marks conventional

GATE - 5 to 7 marks

SSC JE - 9 to 12 marks objective
              20 to 40 marks conventional 

Basics of Design Steel structure 
Nominal diameter = The diameter of the shank of a rivet before riveting ,is called the nominal diameter .For a bolt ,the diameter of the unthreaded portion of the shank is called its nominal diameter .

Effective diameter or gross diameter : The effective or gross diameter of a rivet is equal to the diameter of the hole it fills after riveting . For a bolt ,the nominal diameter is same as the gross diameter .

Net area : The net area of a bolt  is the area at the root of thread .
                                                                                                                       DOWNLOAD                                                                                           
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 2>  The flange angle must be unequal angles with larger legs connected  to flange plate to get more bearing area .

3>  The size of the flange angle should be such that they should form atleast one third  of the total flange area .

4> If d/tw> 90 ,vertical stiffeners are provided to prevent bucking of web due to diagonal compression .

Creadit IndiaMART

5> Vertical stiffeners are provided under point loads .they prevent web crippling or web crimpling or local bucking of web . These stiffeners are called load bearing stiffeners .(web crippling occurs due to excessive bearing stress at the toe of flange angle as shown in figure )

6> If d/w>200 horizontal stiffeners OR longitudinal stiffners are provided about neutral axis at a distance of.2dw form the compression flange .(they prevent bucking of web due to bending compressive stress.

7> if d/w> 250 additional horizontal stiffner is provided at neutral axis.this stiffner prevents buckling of web between stiffners due to shear force .

8> if d/w >400 then the section must be redesigned .

9> At the support ,to prevent bending of flange plate and buckling of web plate due to support reaction ,end bearing stiffeners are used .

10> If bearing stiffners are the only means of providing torsional restraint ,then they are also called torsional stiffeners .(The other means of providing torsional restraint is extending the plate girder into the wall)