Steeledge Steel Scaffolding LLC is engaged in manufacturing and supplying high quality steel Highway Guard Rails, with proven efficacy. While we have wide experience in manufacturing and supplying these products within Dubai (UAE), we are also exporting them in different parts of the globe as well. And, needless to say, we have been successful in carving our niche in the highly competitive market of Manufacturers, Suppliers and Exporters of steel products.
The Highway Guard Rails supplied by us can be easily installed and eliminates the need for skilled labor. Long life, strength, durability and superior performance are the unmistakable attributes of our products. And, you can get all this within competitive price brackets.
This specification covers Corrugated sheet steel prepared for use as beams in highway guardrails. Two classes and four types of guardrail are provided as follows :
Orders for guardrail under this specification shall include the following information, as required, to describe adequately the desired material :
The beam, transition, end and buffer sections shall consist of sheet made of open hearth, electric furnace or basic oxygen steel.
Mechanical Properties :
The mechanical properties of the base metal shall conform to the following requirements:
Beams and transition sections :
End and buffer sections :
Test specimens for mechanical properties shall be prepared and tested as specified in ASTM A 525 except that correction for thickness of zinc coated specimens shall be 0.003 in. (0.08 mm) for Type 1 beam and 0.006 in. (0.15 mm) for Type 2 beam.
The chemical composition of the base metal for Type 4 beams shall be as approved by the Engineer.
The nominal thickness for the finished beam or sheet shall conform to the requirments as prescribed in Table 1
For fabricated beams, thickness measurements will be made on tangent portions of the cross-section.
The beam elements shall be formed from sheets having nominal widths of 19 inches (483 mm) for W-Beams and 29'12 inches (749 mm) of Thrie Beams. Tolerance from the nominal width of minus '18 inch (3.2 mm) will be permissible.
NOTE: The requirements of paragraph 5.1 are intended to define the minimum width sheet permissible. Calculation of exact width dimensions from Figures 1 and 2 shows that the finished product may slightly exceed these widths. However, the dimensions of Figures 1 and 2 can be met within allowable tolerance by using the nominal widths. Use of sheets slightly greater than the nominal widths is permissible provided the tolerances in Figures 1 and 2 are met.
Beam or Sheet Thickness
|Type||Thickness||Tolerance under specified thickness. No limit for over thickness||Thickness||Toleranace under specified thickness. No limit for over thickness|
Weight of Coating
|Type||Min Check Limit Single-SpotTest oz/ft3 g/m3||Min Cheek Limit Triple-SpotTcst oz/ft3 g/m3|
Beams which are to be painted shall be cleaned and shop painted with one coat of rust-inhibitive primer. The primer shall have a tough and durable surface and shall be thoroughly dry before the sheets are handled or packed for shipment.
Beams of corrosion resistant steel shall not be painted or galvanized. They shall be so handled and stored that the traffic face of these beams, used in a continuous run of guardrail, shall not show a distinctive color differential.
End or buffer sections shall be of the same or greater thickness of metal and the same Type as the beam to which it is attached or the engineer may specify the minimum thickness of metal and Type.
The beams and end or buffer sections shall be shaped and punched in conformance with the requirements shown in Figures 1 and 2. Transition sections shall be fabricated in accordance with Figure 4 and shall provide a smooth and uniform transition between beams. They shall be ready for assembly when delivered. Only drilling or cutting necessary for special connections and for sarnpling will be permitted in the field. Warped or deformed beams will be rejected. Beams to be erected on a radius of 150 feet (45 m) or less shall be shop curved to the appropriate curvature of the installation.
All connections or splices shall be formed with oval shoulder button headed bolts to minimize projections on the road side of the guardrail. Unless otherwise specified, bolts and nuts for Types 1, 2 and 3 beams shall conform to or exceed the requirements of ASTM A 307 and shall be hot-dip zinc coated in accordance with the requirements of AASHTO M 232, Class C. When specified by the Engineer to be mechanically galvanized, bolts and nuts shall be mechanically zinc coated and the coating shall conform to the coating thickness, adherence and quality requirements of AASHTO M 232, Class C. Bolts and nuts for Type 4 beams shall be of an approved corrosion resistant material and conform to or exceed the requirements of ASTM A 307. Splice and post bolts and nuts shall conform to one of the configurations shown in Figure 3. Either of the alternate configurations may be furnished unless otherwise specified by the Engineer.
Washers shall be rectangular as shown in Figure 1. Washers for Types 1, 2 and 3 beams shall be galvanized in accordance with the requirements of AASHTO M 232. Washers for Type 4 beams shall be of an approved corrosion resistant steel. Back-up plates if specified for use at nonsplice points shall consist of one-foot (305 mm) sections of beams and shall be ofthe same Class and Type specified for the full length beams.
Where the galvanizing on guardrail or fittings has been damaged, the coating shall be repaired by regalvanizing or the surface repaired by painting with two coats of zinc dust-zinc oxide paint confirming to Federal Specification TT-P-641 or MIL-P-21035.