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Structural Steel

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Type of Steel

Designated by the letter “A” followed by the American Society for Testing and Materials (ASTM) designation number.

The principal types of structural steel include:– A36 carbon structural steel

– A572 high-strength low-alloy structural steel

– A588 corrosion-resistant high-strength low-alloy structural steel.

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Table 1, Rolled-steel shape designations

Type fo shape Example designationW shape W27 x 114S shape S20 x 95M shape M8 x 25American Standard Channel C12 x 30Miscellaneous Channel MC 12 x 50HP (bearing pile) shape HP 14 x 89Equal leg angle L 6 x 6 x 1/2Unequal leg angle L 8 x 4 x 1/2Plate PL 1/2 x 12

Weight: 40.8 lb/sq. ft/ in

1”

1’

1’

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Steel Sections:Channel C 8x11

C = channel

8 = nominal depth

weight = 11.5 #/Lf

Use: beams and built-up members

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Steel Sections:Angle L 5 x 3 x 5/8

L = angle

5 = length of one leg

3 = length of another leg

5/8 = nominal thickness

need to look up # Bracing and build-up members

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StructuralWT 7 x 49.5ST 9 x 35

WT = cut from wide flange (14 x 90)

7 = nominal depth49.5 = #/lfST = cut form S beam (18 x

70)Use: Build-up sections

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Wide FlangeW14 x 9014 WF 90

W = wide flange

14 = nominal depth

90 = #/lf

use: beam and column

Standard BeamS18 x 7018 I 70

Standard BeamS18 x 7018 I 70

S = standard18 = nominal depth70 = #/lfuse: beam, not column

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Estimating Tips Nominally taken off and priced by weight Group for take off by:

– Grade of steel– Type of section or member– Method of tied connection– location

Maintain consistent sequence of take off. Common:– Columns and detail– Beams and detail (floor by floor)– Bracing and flooring

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Pricing Depends on where material is purchased.

– Mill price apply to large orders.

– Warehouse price apply to small orders from local supplier.

Prices are as of time of delivery. Need escalation clauses to be clearly set forth.

Price is made up a base plus extras.

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Pricing Structural Shapes Prices are expressed in cents per pound. W14x95 - 32.68 ft, A36 steel (3104.6#)

– Base 17.00– Dimension: shape 0.45

length-quantity 1.00– Pack 0.00– Mark 0.00– Load 0.20

18.65

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Example Drawing for Structural Steel Take-Off28

’0”

W14

x 4

328

’0”

14’0

”14

’0”

W14

x 4

3W

14 x

43”

W14

x 4

3

W14

x 4

3W

14 x

43

W14

x 4

3W

14 x

43

W14

x 8

4

W14

x 8

4

W14

x 8

4

W14

x 8

4

W14

x 8

4W

14 x

84

W14

x 8

4W

14 x

84

W18 x 40 W18 x 40

W18 x 50W18 x 50

W18 x 40 W18 x 40W18 x 70 W18 x 70

W18 x 70W18 x 70

W14

x 1

03W

14 x

103

W14x 68 W14x 68

W14x 68 W14x 68 W14x 43W14x 43

W14x 43W14x 4320’0” 20’0”30’0”30’0”

All Columnsthis RowW24 x 68

All Columnsthis RowW24 x 100

All Columnsthis RowW24 x 100

All Columnsthis RowW24 x 100

All Columnsthis RowW24 x 68

NOTE:All columns are 12’0” in length

N

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Table 2, List of Steel Quantities

The cost of plates and connectors (bolts or welding) are not included.

Section Number Length (ft) Total Length Wt./ft Total Wt. (lb)W 14 x 43 4 20.0 80 43 3440W 14 x 68 4 30.0 120 68 8160W 18 x 40 4 20.0 80 40 3200W 18 x 70 4 30.0 120 70 8400W 18 x 50 2 20.0 40 50 2000W 14 x 43 4 28.0 112 43 4816W 14 x 43 4 14.0 56 43 2408W 18 x 84 4 28.0 112 84 9408W 18 x 84 4 14.0 56 84 4704W 14 x 103 2 28.0 56 103 5768W 24 x 68 10 12.0 120 68 8160W 24 x 100 14 12.0 168 100 16800