ITEM 442 METAL FOR STRUCTURES

ITEM 442
METAL FOR STRUCTURES
442.1. Description. This Item shall govern for all structural steel, high strength bolts, forgings, steel
castings, iron castings, wrought iron, bronze, steel pipe and tubing, aluminum castings and tubing, and other
miscellaneous metals used in structures, except reinforcing steel and metal culvert pipe.
442.2. Process. All ferrous metals furnished for use under these specifications shall be made by one
or more of the following processes only:
Open-hearth, basic oxygen, or electric furnace.
Mill test reports, supplemental test documentation and certifications required by this Item shall be
furnished to the Engineer.
442.3. Structural Steel.
(1) Steel for Bridge Structures.
Unless otherwise shown on the plans, structural steels for bridge structures shall be in accordance with
ASTM A709.
Unless otherwise shown on the plans, impact testing requirements for all grades of steel shall conform
to the supplemental requirements of S83 or S84 of ASTM A709 for tension components of a bridge member
that consist of components of tension members and those portions of a flexural member that are subject to
tension stress. The geographical boundaries of Zone 1 consists of all counties in Texas below a line which
runs west to east below Deaf Smith and Collingsworth counties. Zone 2 shall include all counties above this
line.
(2) Steel for Non-Bridge Structures.
Unless otherwise shown on the plans, structural steels for non-bridge structures listed herein shall
conform to the longitudinal Charpy V-notch requirements of Table A for tension components of a member
consisting of components of tension members and those portions of a flexural member that are subject to
tension stress. Sampling and testing shall be in accordance with ASTM A673. The (H) frequency of heat
testing shall be used for all material with 36 ksi and 50 ksi minimum yield points. The (P) frequency of
testing shall be used for all material designated as FCM's and for ASTM A514 or A517 steels.
(a) Carbon Steel. When shown on the plans and in the proposal as Structural Steel-HYC, the
material shall conform to the requirements of ASTM A36.
(b) High Strength Steel (HS). High strength steel shall have a minimum required yield point of 50
ksi, and will be shown on the plans and in the proposal as Structural Steel-HS.
Structural Steel-HS shall conform to one of the following ASTM Steels subject to thickness and
physical requirements of the pertinent ASTM Specification:
1.
ASTM A572, High-Strength Low-Alloy Columbium Vanadium Steels of Structural Quality
With 50 ksi Minimum Yield Point To 4 Inch Thickness. Supplemental Requirement S18, for a
maximum tensile strength of 95 ksi, shall be applicable to material used for sign, signal and
luminaire supports.
2.
ASTM A588, High-Strength Low-Alloy Structural Steel With 50 ksi Minimum Yield Point To
4 Inch Thickness.
3.
A36M50, a special designation for ASTM A36, Structural Steel modified to 50 ksi minimum
yield point and a minimum elongation of 18% (8") or 21% (2") and a tensile strength between
65 and 95 ksi. Chemical requirements shall meet ASTM A36 except that the maximum
manganese content shall be 1.35%. Alloys containing Columbium (0.035% maximum) and
Vanadium (0.06% maximum) are permissible.
TABLE A
LONGITUDINAL CHARPY V-NOTCH REQUIREMENTS
Material
Thickness
Inches
Group 1
See Notes
Group 2
See Notes
A36 and
A242
Up to 4"
15 ft. lb.
at 70 F
15 t. lb.
at 40 F
Up to 4"
15 ft. lb.
at 70 F
15 ft. lb.
at 40 F
Up to 2"
welded
15 ft. lb.
at 70 F
15 ft. lb.
at 40 F
Over 2"
20 ft. lb.
at 70 F
20 ft. lb.
at 40 F
25 ft. lb.
at 30 F
25 ft. lb.
at 0 F
25 ft. lb.
at 30 F
25 ft. lb
at 0 F
35 ft. lb.
at 30 F
35 ft. lb.
at 0 F
A572*
mechanically
fastened
and
A588*
to 4"
welded
Up to 4"
A514
mechanically
fastened
and
Up to
2-1/2"
welded
Over
A517
2-1/2" to
4" welded
Notes:
Group 1: Minimum Service Temperature 0 F and above.
Group 2: Minimum Service Temperature from -1F to -30F.
The geographical boundaries of Group 1 consists of all counties in Texas below a line which runs West to
East below Deaf Smith and Collingsworth Counties. Group 2 shall include all counties above this line.
*If the yield point of the material exceeds 65 ksi, the temperature for the CVN value for acceptability shall be
reduced by 15 degrees F for each increment of 10 ksi or fraction thereof above 65 ksi.
(c) Extra High Strength Steel (XHS). Extra high strength steel when shown on the plans shall have
a minimum required yield point of 90 ksi and will be shown on the plans and in the proposal as Structural
Steel-XHS. When so specified, the steel shall conform to the following:
1.
ASTM A514, High-Yield Strength, Quenched and Tempered Alloy Steel Plate.
The steel furnished shall be suitable for welding. Structural shapes and seamless tubing, meeting the
other requirements of A514 steels, will be permitted with a maximum tensile strength of 140 ksi for
structural shapes and 145 ksi for seamless tubing.
2.
ASTM A517, Pressure Vessel Plates, Alloy Steel, High-Strength, Quenched and Tempered.
The above listed steels are considered weldable. Other steels will require qualification in accordance
with ANSI/AASHTO/AWS Bridge Welding Code D1.5 or ANSI/AWS Structural Welding Code D1.1,
whichever is applicable, prior to their use.
(3) Miscellaneous Steel.
(a) Unless otherwise shown on the plans, structural steel for members such as shoes, diaframs,
stiffeners (including bearing stiffeners), lateral bracing, diagonals, armor joints and finger joints shall conform
to ASTM A36 or A500, Grade B.
Structural steels used for secondary or nonstress-carrying members will not be subject to impact
requirements.
All steels greater than 1/2 inch in thickness used for structural supports for highway signs, luminaries
and traffic signals shall conform to the longitudinal Charpy V-notch requirements of Group 1 in accordance
with Table A. Charpy V-notch tests will not be required for pipe used in structural supports.
(b) Stud shear connectors, slab anchors and anchors on armor joints and finger joints shall conform to
the requirements of ASTM A108, cold drawn bars, Grades 1010, 1015, 1018 or 1020, either semi- or fullykilled.
Tensile properties as determined by tests of bar stock after drawing or finishing shall conform to the
following:
Tensile Strength (Min.)
Yield Strength (Min.)
Elongation (Min.)
Reduction of Area (Min.)
60 ksi
50 ksi
20% (2")
50%
Tensile properties shall be determined in accordance with the applicable section of ASTM A370.
The manufacturer shall certify that the studs or anchors as delivered conform with the material
requirements of this section.
(c) High strength bolts, nuts and washers will be sampled for tests in accordance with Test Method
Tex-719-I. High strength bolts shall conform to the requirements of ASTM A325 or A490, unless otherwise
shown on the plans.
Tests, test reports and supplemental requirements for high strength bolts, nuts and washers shall be in
accordance with Item 447, "Structural Bolting".
When high strength bolts are not required, bolts conforming to ASTM A307 and nuts conforming to
ASTM A563 shall be used.
(d) Steel piling shall conform to the following:
Type
ASTM Designation
Steel H Piling
A36
Sheet Piling (Rolled)
A328*
Sheet Piling (Formed) A570* Grade 36
*A mill certificate shall be furnished by the manufacturer certifying to the results of tests required by
the governing specifications.
Sheet piling of a different configuration than that shown on the plans may be used provided the section
modulus and weight per foot furnished is equal to or greater than shown on the plans.
(e) Deck Plates. Material for deck plates shall conform to the following:
Corrosive resistant structural steel conforming to ASTM A242. The material must be of weldable
quality, and shall contain alloying elements that furnish corrosion resistance of at least twice that of copper
bearing structural steel. The type of material to be used with its trade name, shall be stated on the shop
drawings.
(f) Rail Posts. Material for rail posts shall conform to the requirements of ASTM A36 unless
otherwise shown on the plans.
442.4. Steel Forgings. Steel forgings from which pins, rollers, trunnions, or other forged parts are to
be fabricated, shall conform to the requirements of the Standard Specifications for Carbon-Steel Forgings for
General Industrial Use, ASTM A668, Class C, D, F or G. The above will govern for all railroad underpass
structures. The class of material shall be as shown on the plans.
For other structures, for pins four (4) inches in diameter or less, material conforming to ASTM A108,
Grades 1016 to 1030 may be used. The material shall have a minimum yield point of 36 ksi. All forgings
shall be thoroughly annealed prior to being machined to form finished parts. Material for pins over four (4)
inches in diameter shall be in accordance with ASTM A668, Class C, D, F or G. The class of material shall
be as shown on the plans.
442.5. Steel Castings. Steel castings shall conform to the specifications for Mild to Medium Strength
Carbon Steel Castings for General Application, ASTM A27, Grade 70-36.
When shown on the plans as Class 70, Class 90, or Class 120, the steel castings shall conform to the
specified class of ASTM A486.
442.6. Iron Castings. All iron castings shall be true to pattern in form and dimensions, free from
pouring faults, sponginess, cracks, blow holes, and other defects in positions affecting their strength and value
for the service intended.
The castings specified shall conform to one of the following ASTM Specifications.
Material
Gray-Iron Castings
Malleable Castings
Ductile Iron Castings
ASTM
A48
A47
A536
Grade
Class 30
35018
60-40-18
442.7. Lead. Sheet lead shall conform to the requirements of the Specifications for Pig Lead, ASTM
B29.
442.8. Anchor Bolts. Unless otherwise shown on the plans, plain and threaded bars, headed bolts,
medium and high strength bolts, nuts and washers shall conform to Item 449, "Anchor Bolts".
442.9. Steel Pipe. Steel pipe shall conform to the material requirements shown on the plans, or in
other applicable specifications.
442.10. Steel Tubing. Steel tubing shall conform to ASTM A500, Grade B, unless otherwise shown
on the plans or herein. Tubing conforming to API Standard 5LX, Grade 52, except as noted herein, may be
used if produced by a mill recognized as "authorized to produce pipe with the API monogram" and listed as
such in the standard API specifications.
The following exceptions to the requirements of API 5LX, Grade 52, will be allowed:
Hydrostatic tests will not be required.
In lieu of a mill test report, a certificate from the manufacturer will be required for each lot or
shipment, certifying that the tubing meets the requirements stated above.
442.11. Pipe Rail. Pipe shall be construed to include special extruded and bent shapes and shall be of
the section shown on the plans. Pipe may be rolled or extruded to the shape shown on the plans or may be
cold pressed from a round pipe or flat plate.
If cold pressed, the design of the press and dies shall result in a pipe of uniform section and free from
die marks. After the pipe has been formed to the required section, it shall be cut to the lengths required. The
end cuts and notches shall be made at such angles with the axis of the pipe as required to produce vertical end
faces and plumb posts when required by the plans. Cutting and notching of pipe shall be done with a saw or
machine guided torch or other means that will insure a neat and workmanlike finish.
442.12. Steel Deep Beam Rail. The rail element shall be either 10 gage (0.1345 ± 0.008 inches
nominal thickness) or 12 gage (0.1046 ± 0.008 inches nominal thickness), exclusive of protective coating, as
shown on the plans. Rail element shall meet all requirements of AASHTO M-180 except as modified on the
plans.
The terminal connector shall be of the same material, but shall not be less than 10 gauge.
Unless otherwise shown on the plans the rail element shall be galvanized in accordance with Item 445,
"Galvanizing".
442.13. Aluminum.
(1) Unless otherwise shown on the plans, aluminum materials shall
conform to the following:
Castings
Extrusions
Sheet & Plate
ASTM B108, Alloy A444-T4
ASTM B221, Alloy 6061-T6
ASTM B209, Alloy 6061-T6
Test specimens from castings shall be cut from the lower 14 inches of the tension flange but not at the
junction of the rib or base. The curved surfaces shall be flattened prior to machining. Test specimens shall
conform to ASTM E8, Figure 8.
442.14. Fabrication, Erection, and Painting. Fabrication, welding, and erection of structural metal
shall be in accordance with Item 441, "Steel Structures", Item 448, "Structural Field Welding", Item 447,
"Structural Bolting", and the ANSI/AASHTO/AWS Bridge Welding Code D1.5 or the ANSI/AWS Structural
Welding Code D1.1, whichever is applicable. Paint and painting shall be in accordance with Item 446,
"Cleaning, Paint and Painting". Aluminum or galvanized steel members shall not require painting, unless
otherwise shown on the plans.
442.15. Galvanizing. Galvanizing of fabricated steel items, steel or iron castings, bolts, nuts, screws,
washers and other miscellaneous hardware shall be in accordance with Item 445, "Galvanizing".
Galvanizing will not be required for any material unless specified on the plans or in the specifications.
442.16. Measurement. This Item will be measured by the pound of structural metal furnished and
placed in a complete structure, exclusive of the weight of erection bolts, paint, or weld metal.
This is a plans quantity measurement Item and the quantity to be paid for will be that quantity shown
in the proposal and on the "Estimate and Quantity" sheet of the contract plans, except as modified by Article
9.8. If no adjustment of quantities is required, additional measurements or calculations will not be required.
The maximum percent variance from the plans quantity will be as follows:
Percent Variance
Quantity
Over 1,000,000 Lbs.
100,000 through l,000,000 Lbs.
less than 100,000 Lbs.
Percent
1/2 %
1%
l-1/2 %
When increases in size or weights of members have been made which were not ordered but were
approved by the Engineer, the measurement will be made on the sizes or weights shown on the contract plans.
In determining the weight of structural metal in steel or concrete structures, such items as castings,
bearing plates, anchor bolts, drains, deck plates, armor joints, finger joints, and all other metal for which no
separate measurement is specified will be included in the total quantity of Structural Steel.
The weights of rolled shapes and plates will be computed on the basis of their nominal weights and
dimensions using English measurements as shown on the approved shop drawings. The weight of castings
will be computed from the dimensions shown on the approved shop drawings. Shoes will be measured by the
weights shown on the contract plans, or as specified for castings, if weights are not shown.
Deductions will be made for all cuts, copes, perforations, and all holes except bolt holes.
When computed, the weight of metal will be based on Tables B or C.
Splices will be measured as follows:
(1) No additional weight will be allowed for weld metal in a welded splice.
(2) Where a bolted splice is permitted as an alternate for a welded splice, measurement will be made
on the basis of a welded splice.
(3) Where a bolted splice is required, the weight of splice material, bolts, bolt heads, washers, and
nuts, with no deduction for holes, will be measured.
TABLE B
Pay Weights-Lbs. per Cu. In.
Material
Steel
Cast Iron
Wrought
Iron
Bronze
Lead
Weight
0.2833
0.2604
0.2777
0.3150
0.4085
TABLE C
High Strength Bolts-Pounds per Hundred Units
Diameter
1/2"
5/8"
3/4"
7/8"
1"
1-1/8"
1-1/4"
Bolts Heads
15
25
36
52
73
Nuts
19
28
21
56
73
Washers
12
12
18
21
27
442.17. Payment. The work performed and materials furnished in accordance with this Item and
measured as provided under "Measurement" will be paid for at the unit price bid for "Structural Steel-HYC",
"Structural Steel-HS", or for such other classifications of metal as shown on the plans and in the proposal.
This price shall be full compensation for furnishing all materials; for all fabrication, shop work, transportation,
erection, paint, painting, galvanizing; and for furnishing all equipment, tools, labor and incidentals necessary
to complete the work.