SECTION 606 - GUARD RAIL
606.01 Description. This work consists of furnishing and erecting complete sections of
guard rail in accordance with these specifications and in reasonably close conformity with the lines and grades shown on the plans or established by the Engineer. This work shall also include the installation of reflectors on guard rail posts and the installation of guard posts. When the work requires the removal and replacement of guardrail on a facility opened to traffic, the materials necessary for replacement will be on hand before removal begins. The Contractor shall not begin work on any section of guardrail until preparations have been made to complete the installation of the section, including posts, rail, anchors, and hardware as a continuous operation. Once work has been initiated on a section, the work shall be prosecuted to its completion unless inclement weather or other conditions beyond the control of the Contractor interfere with the work. Uncompleted guardrail or special end sections shall not be left exposed to th e travelling public without the approval of the Engineer. If approval is granted, the uncompleted section must satisfactorily be marked with drums, barricades, or other devices, as directed by the Engineer, at no additional cost to the Department. In no case will uncomplet ed guardrail or special end sections be allowed to remain over a weekend or holiday period.
606.02 Materials. Unless otherwise specified, all materials shall conform to the
requirements shown on the plan s and set forth in Section 712. Reflectors shall be of the type, size, and color designated on the plans and shall conform to the requirements of Subsection 721.07. When not designated, guard rail posts, mee ting the requirements of Subsection 712.06, may be wood or steel but shall be of the same type for the entire project. Posts for bridge end sections shall be of the same type as the guard rail line posts. Posts for cable anchorage sections may be wood or steel but shall be of the same type for the entire project. Terminal end sections, installed as per manufacturer’s recommendations, shall be NCHRP Report 350 or MASH approved. Terminal end sections shall be Flared or Non-Flared and shall be one listed on the Department’s APL. The end sections shall be installed in accordance with the manufacturer’s recommendation. Prior to installation, the Contractor shall provide two copies of the manufacturer’s installation details to the Project En gineer. The Project Engineer will keep one copy in the project file and provide one copy to the District Maintenance Engineer. The installation details shall be engineering drawings, a minimum of 11” X 17” in size. Reflective adhesive sheeting with alternating black and yellow stripes (sloping downward at an angle of 45 degrees in the direction traffic is to pass) shall be required on the end of the terminal section. The type of terminal section installed shall be written on the device with a Permanent Marking Stick or some other means of permanent identification.
606.03 Construction Requirements.
606.03.1 Erection of Guard Posts. Generally, guard post will be constructed of timber
post. However, in certain circumstances, gu ard post may be constructed of steel with special requirements as detailed on special design sheets in the plans. The posts shall be set plumb and firm to the depth indicated and accurately lined, spaced, and graded. After the posts are in place, the holes shall be backfilled with suitable material which shall be thoroughly compacted in approximate six inch layers by tamping. Posts shall not be sawed or cut after treatment. If set posts are found to be in improper position with reference to alignment or grade, they shall be removed and reset properly. If the posts are found too high they may be driven to the proper elevation provided the tops of the posts are protected by suitable driving caps. Wood guard rail posts and guard posts may be erected by driving or by a combination of drilling and driving when after demonstration at the project site the Engineer approves the results as being equal to or better than the results that can be obtained by erecting posts in drilled holes and backfilling. Acceptability of driving or combined drilling-driving will be contingent on the following conditions:
a.Use of approved and proven mechanical driving equipment;
b.Maintenance of acceptable results without impairing the structural integrity of adjacent materials or structures;
c.Use of drills to penetrate courses that may resist penetration by driving. When drills of nominal post-size are used the void between the post and the edge of the hole shall be filled with Grade AC-13 asph alt. Holes larger than nominal post- size drilled through paved surfaces or cem ent treated courses shall be properly backfilled with hot or cold bituminous pavement;
d.Out-of-tolerance posts shall be pulled and properly replaced or reset, and all disrupted portions of the roadbed structure restored as directed; and
e.Mutilated posts shall be pulled and prope rly replaced, and all disrupted portions of the roadbed structure restored in kind or as directed. Steel guard rail posts may be erected by driving, provided an approved driving head is used. The top inside edges of posts shall be set within 1/4 inch of correct vertical and horizontal alignment. Guard rail posts on bridges shall be plumb and accurately spaced and lined. Where sections of rail are located on curves, th e posts shall be erected so as to obtain the designated panel lengths measured along the face of the rail.
606.03.2 Anchorage. Anchors and braces shall be furnished and placed as shown on the
plans.
606.03.3 Erection of Rails . All fabrication and forming of rail elements shall be
completed prior to application of the shop paint. Field punching, cutting, burning, or welding will not be permitted, except where specifically authorized by the Engineer and subject to the conditions thereof. The rail shall be erected in a manner that results in a smooth, continuous, taut rail that conforms to the line and grade sh own on the plans or established. In the erection of rail, consideration shall be given to the prevailing temperature and the anticipated rise and fall of temperature ultimately affecting the length of the rail. Where required, ends of rail shall be flared within the limits shown on the plans or established. Bolts and clips used for fastening rails or fittings to posts shall be drawn up tightly, and all bolts, except "take up" device bolts, shall be of such length as to not project beyond the nut more than the limits shown on the plans. Sawing of ends of bolts to meet this requirement will be permitted.
606.03.4 Repairing Rails and Fittings . Where the galvanizing on guardrail or fittings
has been damaged, the coating shall be repaired by re-galvanizing or the surface repaired by painting with two coats of zinc oxide paint approved by the Engineer.
606.03.5 Reflectors. Reflector units shall be installed in conformity with details shown
on the plans and in accordance with the ma nufacturer's recommendations. Where holes are required to be bored in posts or other units, the holes shall be bored prior to the required painting. The reflectors shall be installed after all painting is completed.
606.04 Method of Measurement. Guard rail will be measured by the linear foot along
the face of the rail from center to center of end posts for each complete section and will include posts and other elements of the completed section. Special sections will be measured per each or linear foot, as indicated on the plans. Guard posts will be measured by the unit per each post installed. Such measurement will
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Source: Standard Specifications for Road and Bridge Construction, 2017 Edition. Pages 421–423 of 1,113. View official source ↗