623CURB, GUTTER, AND COMBINATION CURB AND GUTTER

506

The foundation shall be constructed or excavated to the required depth below the finished surface in accordance with the cross section shown on the plans or as designated. All soft or other unsuitable material shall be removed and replaced with suitable material, in layers not to exceed 4 inches {100 mm} compacted. The foundation shall be compacted as provided for the applicable types of material involved.

If provided by the plans and/or proposal, foundation backfill to replace unsuitable material shall be placed and constructed as provided in Section 214. No direct payment will be made for foundation backfill, except when the proposal includes a unit price for this pay item.

The Contractor shall use standard type metal forms as noted herein or, if requested in writing and approved by the Department, an approved automatic extrusion type curb and/or gutter machine.

These forms shall be metal, except for radial sections, straight, and free from warps and of sufficient strength, when staked, to hold the concrete true to line and grade without distortion. They shall provide the approved typical section and depth of the section shown on the plans. Radial or curved forms may be of flexible metal or a wood form of approved design. Bent or damaged forms shall not be used. All forms shall be securely staked, braced, and held together to the exact lines and grades established and shall be kept sufficiently tight to prevent leakage of mortar. All forms shall be cleaned and oiled with a suitable oil immediately before concrete is placed against them.

Any automatic extrusion type curb and/or gutter machine considered for approval must be demonstrated to produce a section conforming to the dimensions, cross-section, lines, and grades shown on the plans within the tolerances provided in Item 623.03(h)2 for formed curbs and/or gutters. Failure to consistently produce an acceptable product shall be cause to withdraw approval of the machine and order the use of standard forms. All types of curbs, gutter, and combinations shall be placed in one operation, to the depth of cross section specified on the plans. The use of a two stage operation will not be permitted.

Gutter, curb, and combination curb and gutter shall be constructed in sections of the lengths shown on the plans. The length of section may be reduced where necessary to form closure.

The handling, storage, proportioning, and mixing of concrete shall conform to the requirements of Section 501.

All expansion, contraction, and construction joints shall be constructed as shown on the plans and in accordance with the requirements of Article 501.03. If not shown on the plans, joints shall be placed as follows:  Expansion joints shall be placed in curb and/or gutter to match those in concrete pavement where the two are adjacent.  Expansion joints shall be 3/4 of an inch {20 mm} wide. They shall be placed where curb, gutter or combined curb and gutter terminate against concrete driveways and other concrete structures except inlets. The joints shall be placed at least 20 feet from the location of the termination of the curb, gutter or combined curb and gutter at inlets.  Expansion joint filler and sealer shall meet the requirements given of Articles 832.01 and

832.02. Expansion joint filler shall extend from the bottom of the curb and/or gutter to

within 1 inch {25 mm} of the top; the sealer shall be 3/4 of an inch {20 mm} thick and shall be recessed 1/4 of an inch {6 mm} from the top.  Contraction joints shall be placed in curb and/or gutter to match those in concrete pavement where the two are adjacent, but in no instance more than 20 feet {6 meters} between joints. The contraction joints shall be sawed or otherwise cut 2 inches {50 mm} CURB, GUTTER, AND COMBINATION CURB AND GUTTER 507

deep by 1/8 of an inch {3 mm} wide and shall extend 2 inches {50 mm} below the pavement surface.

The subgrade and forms shall be checked and approved just prior to placing concrete against them. All debris or other foreign material shall have been removed from the space to be occupied by the concrete. The subgrade shall be moist but not wet or muddy. After mixing, the concrete shall be placed in the forms and shall be tamped, spaded, or vibrated sufficiently to produce a dense homogeneous mass and to bring the mortar to the surface. Particular attention shall be given to spading the concrete along and against the surface of the forms to prevent honeycombing and secure a smooth, uniform surface.

When the forms are filled, the concrete shall be struck off with a template, cut to the curb edge design. The exposed concrete surface shall then be finished smooth with a wooden float in a manner that will compact the mass and produce a true, even top surface. Plastering with mortar to build up or finish will not be permitted. The surface of the gutter and the face and top of the curb shall be checked with a 10 foot {3 m} straightedge and any irregularities more than 1/4 of an inch in 10 feet {6 mm in 3 m} corrected. The alignment and grade shall not at any point vary more than 1/2 of an inch {10 mm} from that established by the elevation control stakes. Excessive troweling with a steel trowel will not be permitted. A textured finish shall be provided on the exposed surface just before the concrete becomes nonplastic by the use of a burlap or cotton fabric drag, brush, or broom which will produce a uniform gritty texture along the length of the curb, gutter, or combination curb and gutter. The upper edges of curb and gutter shall be rounded with an approved edging tool to the radius shown on the plans. The joint templates shall be set during the placing of the concrete and allowed to remain in place until the concrete has set sufficiently to hold its shape, but shall be removed while the forms are still in place. The forms shall be left in place until the concrete has set sufficiently so that they can be removed without damage to the work, but, unless otherwise directed, they shall be removed within 24 hours after the concrete has been placed. Immediately after the removal of the forms, the repair of any minor defective areas shall be accomplished.

The requirements of Subarticle 623.03(h) are applicable except that fixed forms are not required.

Immediately after the finishing operation is completed, the concrete shall be cured as provided by Subarticle 450.03(m). If mats are used, they shall be kept continuously moist for a period of at least 72 hours. During this period, and until completion and acceptance of the work, it shall be protected from damage by the elements or other cause.

After the concrete has set sufficiently, spaces along the front and back sides of the gutter, curb, or combination curb and gutter, shall be backfilled to the required elevation with suitable material which shall be compacted by tamping with approved metal tamps or mechanical tamps in layers not more than 4 inches {100 mm} thick until firm and solid.

623.04Method of Measurement

Accepted Concrete Gutter, Concrete Curb, and Combination Curb and Gutter will be measured in linear feet {meters}, complete in place, to the nearest 0.1 foot {0.1 m} along the base of the curb face or along the flow line of the gutter continuing on such line extended across driveways, alleyways, and other entrances. Measurement for separate payment for Foundation Backfill will only be made when Item 214-B is provided in the proposal.

623.05Basis of Payment

The accepted length of Concrete Gutter, Concrete Curb, and Combination Concrete Curb and Gutter, measured as provided above, will be paid for at the respective contract unit prices, complete in place, which shall be payment in full for all excavation, backfilling, disposal of surplus material, all joints, all special construction at driveways and other entrances and other points, furnishing all materials, hauling and placing materials, and for all labor, equipment, tools, and incidentals necessary CABLE GUIDERAIL 508

to complete the work in accordance with the specifications including all approaches through curb and gutter indicated on the plans.

623-A Concrete Gutter - per linear foot {meter} 623-B Concrete Curb, Type ____ - per foot {meter} 623-C Combination Curb & Gutter, Type ____ - per linear foot {meter} CABLE GUIDERAIL

624.01Description

This Section shall cover the work of furnishing and installing posts, anchors, cables and miscellaneous hardware required for the construction of tensioned cable guiderail.

624.02Materials and Design

The cable guiderail system shall be a system accepted by ALDOT and determined by FHWA as passing NCHRP Report 350 or the AASHTO Manual for Assessing Safety Hardware (MASH) requirements for the Test Level, post spacing, slope, placement location, and other details as shown on the plans. The cable guiderail system shall be designed by the manufacturer, specific to the project site, to limit the deflection to the design value shown on the plans. The manufacturer’s design shall take into consideration the locations of the cable guiderail and cable guiderail runs as shown on the plans. The manufacturer shall design anchors for the beginning and ending termini of each cable guiderail run as shown in the plans and shall determine if intermediate anchors within each cable guiderail run are necessary to limit the deflection to the design value.

624.03Construction Requirements

The Contractor shall submit Working Drawings including the manufacturer’s system design and details in accordance with Article 105.02. The contract documents may include information regarding the existing soil, but it is the Contractor’s responsibility to provide the cable guiderail system manufacturer with any geotechnical information needed to design the cable barrier system. The Contractor shall include the manufacturer’s required soil parameters and the results of the geotechnical investigations in the submittal package. The submittal shall include a written statement from the cable guiderail manufacturer that the proposed cable guiderail system’s anchor spacing is adequate to limit the deflection to the design value shown in the plans. The Construction Engineer will not approve the submittal but will review the submittal for completeness.

The Contractor shall be fully responsible for insuring that the cable guiderail system is constructed in compliance with the cable guiderail manufacturer’s recommendations and requirements.

A representative of the cable guiderail manufacturer shall be present at the site of the installation during the various phases of installation to ensure that the Contractor installs all components of the cable guiderail system in accordance with the manufacturer's requirements. The various phases of installation include anchor installation, line post installation, attachment to guardrail, splicing cable, cable tensioning, etc. The manufacturer's representative shall provide training for Departmental personnel applicable to the installation and maintenance procedures for all features of the guiderail. The manufacturer’s representative may also be required to provide training for local first responders regarding precautions to be taken when working in and around crash sites involving the guiderail. The training sessions will be conducted at a location determined by the Engineer and will be of sufficient length to address all training topics.

Within five calendar days after the completion of the installation of all components of the cable guiderail system, the Contractor shall submit a letter from the manufacturer to the Engineer stating that all components of the cable guiderail system, foundations, and all geotechnical conditions are in