903.1 Description. This work shall consist of furnishing and installing highway signs as shown on the plans. All
signs shall be in accordance with the MUTCD. Any signs not detailed on the plans shall be in accordance with Standard Highway Signs by the U.S. Department of Transportation, Federal Highway Administration.
903.2 Material. All material shall be in accordance with Division 1000, Material Details, and specifically as
follows: Item Section/Specification Reinforcing Steel for Concrete 1036 Highway Sign Material 1042 Delineators, Mile and Marker Posts 1044 Paints for Structural Steel 1045 Electrical Conduit 1060 Expansive Mortars 1066 Carbon Steel Bolts, Nuts and Washers 1080 Structural Carbon Steel 1080 Structural Low Alloy Steel 1080 Low-Carbon Steel Anchor Bolts ASTM F1554, Grade 36 High-Strength Anchor Bolts and Nuts ASTM F1554, Grade 55 High-Strength Bolts, Nuts and Washers 1080 Galvanized Coating of Structural Steel and Appurtenances 1081
903.2.1 Sign Posts and Tubular Steel Sign Supports.
Item Section/Specification Perforated Square Steel Tube Posts 1044 Steel Pipe Posts ASTM A53, Grade B, or ASTM A500, Grade B Galvanizing of Steel Pipe Posts ASTM A53 Structural Steel Welding Electrodes AWS A5.1 or AWS A5.5 I-Beam Posts AASHTO M270 Grade 50 or 50w U-Channel Posts ASTM A499, Grade 60
903.2.2 Overhead Sign Trusses.
Item Specification Aluminum Extruded Tube ASTM B221, 6061-T6 Aluminum Permanent Mold Castings ASTM B108, A 356.0-T61 Aluminum Sand Castings ASTM B26, 356.0-T6 Aluminum Plate ASTM B209, 6061-T6 Aluminum Structural Shapes ASTM B308, 6061-T6 Aluminum Pipe Handrail ASTM B241, 6061-T6 or 6063-T6 Aluminum Pipe Fittings for Schedule 10 Pipe ASTM B26, 356.0-T6 or ASTM B108, A 356.0-T61 Aluminum Grating Bearing Bars Cross Bars ASTM B211, 6061-T6 or ASTM B221, 6061-T6 or 6063-T6 ASTM B211, 6061-T6 or ASTM B221, 6061-T6 or 6063-T5 or T6 Aluminum Washers ASTM B209, 2024-T4 or Alclad 2024T4 Aluminum Beveled Washers ASTM B221, 2024-T4 Filler Wire for Welding Aluminum AWS A 5.10 ER5356, ER5556 Stainless Steel U-Bolts ASTM A276 Chromium-Nickel Grade, min. yield 30,000 psi Stainless Steel Bolts, Nuts, Screws and Washers ASTM A320 or SAE J405D, Austenitic Steel, min. yield 30,000 psi Structural Steel Welding Electrodes AWS A 5.1 or AWS A 5.5
903.2.3 Hardware. Anchor bolts, bolts, nuts and washers specified to be galvanized shall be galvanized in
accordance with ASTM F2329. Except for anchor bolts, galvanizing thickness shall not exceed 6 mils. For high strength bolts, the contractor shall furnish to the engineer a copy of the manufacturer's inspection test report for each production lot or shipping lot furnished, and shall certify the bolts furnished are in accordance with Sec 1080.
903.2.4 Concrete. Concrete shall be of the class specified in the contract. Material, proportioning, mixing,
slump and transporting of concrete shall be in accordance with Sec 501 for the specific class specified. Concrete shall be placed, finished and cured in accordance with Sec 703.
903.2.5 Equipment and Material. Equipment and material shall be of new stock unless the contract provides
for relocation of existing units or use of units furnished by others. New equipment and material shall meet the approval of the engineer.
903.3 Construction Requirements.
903.3.1 Footings for Trusses and Posts.
903.3.1 1 Bolt-Down Installations. Bolt-down footings and end supports are those in which anchor bolts are
cast into the footing, such as overhead sign trusses and tubular steel sign supports. Class B concrete shall be used to construct bolt-down footings. Footings shall be formed, unless in the judgment of the engineer, soil conditions permit excavation to be made to the neat lines of the footings and the footings cast against the undisturbed vertical soil face. In all cases, the top 12 inches below finished ground line shall be formed. Footings shall be placed on firm, stable, undisturbed soil to the minimum depth shown on the plans. Backfill shall be thoroughly compacted, and care taken to prevent damage to finished concrete. Backfill shall be brought up level with the finished ground line. Anchor bolts shall be firmly held in proper position, supported at the top, during placement of concrete.
903.3.1 2 Embedded Installations. Embedded installations are defined as footings for pipe posts and I-beam
posts only. Class B or B-1 concrete, or concrete of a commercial mixture meeting the requirements of Sec 501, or prepackaged dry commercial concrete mixture meeting the requirements of Sec 903.3.1.2.1 shall be used for the footings for embedded-type sign posts. Posts shall be supported in proper position until the concrete or other approved material has set. Excavation and backfill shall be in accordance with Sec 903.3.1.1, except forming will not be required unless soil conditions warrant forming. Tops of footings shall be finished flush with the slope of the ground. Footings shall be visually inspected for acceptance by the engineer.
903.3.1 2.1 Pre-packaged dry commercial concrete mixture used for embedded footings shall have a
manufacturer’s 28-day compressive strength rating of no less than 4,000 psi for the footings for embedded-type sign posts. The concrete shall be thoroughly mixed in accordance with the manufacturer’s recommendations. Strength requirements shall meet or exceed Class B concrete as specified in Sec 501.
903.3.1 3 Perforated Square Steel Tube Post Anchor Installations. Construction requirements and concrete
material requirements for perforated square steel tube (PSST) anchor installations shall be in accordance with Sec 903.3.1.2.
903.3.1 4 Optional Footings. Substructures for butterfly and cantilever overhead sign trusses and posts may be
either drilled shafts or spread footings.
903.3.1 4.1 The quantities shown on the plans reflect the total cubic yards of substructure, based upon drilled
shaft quantities.
903.3.1 4.2 No adjustment in payment will be made for providing the equivalent spread footing design that
differs in area from the specified drilled shaft design.
903.3.1 4.3 If rock is encountered and the depth of drilled shafts is adjusted accordingly, cubic yard quantities
will be recalculated for those locations and payment will be adjusted accordingly. Cubic yard quantities will not be recalculated for spread footings if rock is encountered, unless it is considered differing site conditions in accordance with Sec 104.2 of the standard specifications.
903.3.2 Posts for Ground Mounted Signs.
903.3.2 1 Post Lengths. Post lengths shown on the plans for ground-mounted signs are for bidding purposes
only. The contractor shall be responsible for determining post lengths to provide the vertical clearance shown on the plans. Field cutting of posts will be permitted.
903.3.2 2 Post Alignment. Sign posts shall be vertical. Any post bent or otherwise damaged to the extent that
the post is considered unfit for use shall be removed and replaced with an acceptable post at the contractor's expense.
903.3.2 2.1 I-Beam Posts. I-beam sign posts for ground mounting of signs shall be fabricated and erected as
shown on the plans. Welds shall be of full section and sound throughout. Posts with dimensional defects and structural discontinuities will be rejected. Posts built up by welding two lengths together will be permitted, provided the welds are ground smooth and flush with the base metal. Posts and appurtenances shall be hot-dip galvanized after fabrication. Posts with breakaway assemblies shall be cut at the hinge prior to galvanizing, except for field cutting. Hinge plates shall not be attached to the posts at the time of galvanizing. All welds shall be cleaned before galvanizing. All exposed steel areas and damaged galvanizing shall be repaired in accordance with Sec 1081.
903.3.2 2.2 Pipe Posts. Pipe posts shall be fabricated as shown on the plans and shall be hot-dip galvanized after
fabrication. Welds shall be of full section and sound throughout. Posts with dimensional defects and structural discontinuities will be rejected. All welds shall be cleaned before galvanizing. Exposed steel areas and damaged galvanizing shall be repaired in accordance with Sec 1081. Friction caps for pipe posts shall be of the dimensions shown on the plans and may be galvanized steel or aluminum alloy.
903.3.2 2.3 Perforated Square Steel Tube Posts. Perforated square steel tube posts (PSST) shall be installed at
locations shown on the plans. Exposed steel areas and damaged galvanizing shall be repaired in accordance with Sec 1081.
903.3.2 2.4 U-Channel Posts. U-Channel posts shall be installed at locations shown on the plans. Exposed steel
areas and damaged galvanizing shall be repaired in accordance with Sec 1081.
903.3.2 3 Certification. The contractor shall furnish to the engineer the fabricator’s certification that the
material supplied is in accordance with the requirements specified.
903.3.3 Tubular Steel Sign Supports. Tubular sign supports for overhead mounting of signs shall include span,
cantilever and butterfly types, complete with poles, beams, mast arms, sign bracket assemblies and other specified appurtenances. All steel shall be hot-dip galvanized after fabrication in accordance with Sec 1081. All welds shall be cleaned before galvanizing. Shop drawings will not be required for these supports.
903.3.3 1 Tapered Steel Poles and Beams. Tapered steel poles and beams shall be a continuous taper tube,
fabricated from one length of open hearth sheet steel with one continuous welded longitudinal seam. After fabrication, the material shall have a minimum yield strength of 48,000 psi. Straight steel arms shall be standard or extra heavy pipe, of the dimensions and grades shown on the plans. Bolts, nuts, washers, clamps and sign bracket assemblies shall be hot-dip galvanized or of stainless steel. Clamps shall be fabricated of low alloy steel.
903.3.3 2 Certification. The contractor shall furnish to the engineer the manufacturer's certification that the
tubular steel sign supports are in accordance with the requirements specified.
903.3.3 3 Surfaces. Galvanized material shall be handled to avoid damage to the surfaces. Any material on
which the galvanizing has been bruised or broken will be rejected or may, with approval from the engineer, be repaired in accordance with Sec 1081.
903.3.4 Overhead Sign Trusses. Overhead sign trusses shall be steel or aluminum, and shall include all
structural steel, structural aluminum, aluminum castings, pipe railing, gratings, supports and appurtenances above the top surface of the concrete footings. Shop drawings in accordance with Sec 1080 shall be furnished to the engineer for approval.
903.3.4 1 Testing and Certification. The contractor shall furnish to the engineer a copy of certified mill test
reports on all material furnished, providing the actual chemical analysis and the actual results of physical tests. In lieu of mill test reports for secondary members, the contractor may furnish a certification from the fabricator certifying the material supplied is in accordance with the requirements of these specifications. All test reports and certifications shall be furnished to the engineer before any requests for shop inspection are made.
903.3.4 2 Steel Fabrication and Erection. Structural steel fabrication and erection shall be in accordance with
Secs 712 and 1080, except as hereinafter specified.
903.3.4 3 Welder Qualifications. Before starting fabrication of structural aluminum, all welders shall be
qualified in accordance with the latest edition of ANSI/AWS D1.2 – Structural Welding Code, Aluminum. The test specimens shall be made using a base metal of aluminum alloy 6061-T6 using filler metal acceptable for welding this alloy and inert gas shield arc. Requalification may be required any time there is specific reason to question the welder's ability.
903.3.4 4 Welding Inspection. All aluminum welds shall be inspected by the fabricator to verify the reliability
of production as follows:
a.Visual inspection of all welds, proof testing of welds, and sufficient destructive testing of weld samples fabricated during the production welding.
b.Poor welding workmanship noted by visual inspection will be sufficient cause for rejection.
903.3.4 5 Contact Surfaces. Contact surfaces of aluminum flange castings shall be finished to provide at least
50 percent contact after assembly, as indicated by the Standard Machinist's Blue Test.
903.3.4 6 Fabrication of Aluminum Alloy. Fabrication of aluminum alloy material shall be in accordance with
the manufacturer's recommendations and the following requirements. Flame cutting will not be permitted. All holes in castings shall be machined for final fit. Welding shall be done by the inert gas shielded arc method, and flux shall not be used. Precautions shall be taken to avoid scoring or marring of aluminum surfaces. The engineer will reject any scoring or marring that gives an objectionable appearance. Cast parts shall have all casting irregularities removed. Tubing shall be seamless, and exterior and interior surfaces shall be clean, smooth and free from slivers, laminations, grooves, cracks or other defects.
903.3.4 7 Shop Inspection. Shop inspection will be in accordance with Sec 1080.
903.3.4 8 Wind Testing. Simulated wind-shop test loading for aluminum trusses will be required as shown on
the plans. The load in kips and location of the point of application shall be indicated on the shop drawings.
903.3.4 9 Handling and Storage. Handling and storage of material shall be in accordance with Sec 712. If
specified, galvanized high strength bolts and washers shall be in accordance with Sec 903.2.2. Bolts shall be snugly tightened. Connections in which steel and aluminum are in contact shall be protected as shown on the plans.
903.3.4 10 Surfaces. Galvanized and aluminum material shall be handled to avoid damage to the surfaces. Any
material on which the galvanizing has been bruised or broken will be rejected or may, with approval from the engineer, be repaired in accordance with Sec 1081.
903.3.5 Sign Storage, Certification and Erection.
903.3.5 1 Storage of Signs. Signs delivered for use on a project shall be stored in a manner meeting the
approval of the engineer. Any sign damaged, discolored or defaced during transportation, storage or erection may be rejected.
903.3.5 2 Fabricator's Certification. The contractor shall furnish to the engineer, prior to sign erection, the
fabricator's certification stating, "I hereby certify that only material and manufacturing processes in full compliance with the Missouri Department of Transportation job specification requirements were used in the fabrication of signs for Job ___________, Route ___________, County ____________."
903.3.5 3 Erection of Signs. Sign posts shall be set vertically true to line such that the signs will be level, at the
proper angle with the roadway, and with the minimum clearances shown on the plans. Mounted signs shall present a smooth flat surface varying no more than 3/8 inch from a 4-foot straightedge placed in any position on the face of the sign after erection. Signs on traffic signal posts shall be mounted with strap or clamp type sign supports as shown on the plans or as approved by the engineer. Signs shall not be mounted on light poles.
903.3.6 Delineators. Delineators shall be installed vertically and any delineator considered unfit for use by the
engineer shall be removed and replaced at the contractor’s expense.
903.4 Final Cleanup. Final cleanup of right of way shall be in accordance with Sec 104.11.
903.5 Method of Measurement. Final measurement will not be made except for authorized changes during
construction, or where appreciable errors are found in the contract quantity. The revision or correction will be computed and added to or deducted from the contract quantity. Where required, measurements will be made in the following manner. Measurement of concrete for bolt-down footings and embedded footings will be made separately to the nearest 0.01 cubic yard for each footing and to the nearest 0.1 cubic yard for the total, as shown on the plans. No measurement will be made for concrete used in footings for perforated square steel tube posts (PSST).
903.5.1 Measurement of the weight of I-beam and pipe posts will be made to the nearest pound for each post
and to the nearest 10 pounds for the total, as shown on the plans. Weights will be computed using the theoretical weight of the various sections.
903.5.2 Measurement of sign areas will be made to the nearest 1/10 square foot for each sign and to the nearest
square foot for the total. The area of each sign will be that of the smallest rectangular, triangular or trapezoidal shape that will encompass the sign panel.
903.5.3 Measurement of perforated square steel tube and u-channel posts will be made to the nearest linear foot
for each post, as shown on the plans.
903.5.4 Measurement of post anchors for PSST will be made per each for each post anchor type. Measurement
of breakaway assemblies for PSST will be made per each complete assembly.
903.5.5 Measurement of delineators will be made per each.
903.6 Basis of Payment.
903.6.1 Breakaway assemblies for pipe posts and I-beam posts, including the base connection, hinge plate, fuse
plate, structural bolts and all other fabrication, complete in place, are incidental, regardless of the post size or shape. Breakaway assemblies for perforated square steel tube posts, complete in place, will be paid for at the contract unit price each, regardless of the post size.
903.6.2 Highway signing will be paid for at the contract unit price for each of the items included in the contract.
No direct payment will be made for incidental items necessary to complete the work, unless specifically provided as a pay item in the contract.
903.6.3 Delineator posts will be paid for at the contract unit price. No direct payment will be made for reflective
sheeting or post anchors.
903.6.4 Perforated square steel tube (PSST) and u-channel posts will be paid for at the contract unit price for
each of the items included in the contract. PSST post anchor installations will be paid for separately for each anchor type. All costs for PSST footing installations shall be considered included in the cost of the post anchor.
903.6.5 Concrete footings for bolt-down and embedded installations will be paid for separately at the contract
unit price. Excavation, backfilling, reinforcing steel, anchor bolts and nuts, grout and other items shown on the plans will be considered included in payment for concrete footings. No payment will be made for concrete used for the installation of PSST footings.
903.6.6 I-beam and pipe posts will be paid for at the contract unit price for each of the items included in the
contract.
Referenced in this section
Sections that cite this one
Highway Signing in other states
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Source: Missouri Standard Specifications for Highway Construction, 2026 (Oct) Edition. Pages 542–547 of 874. View official source ↗