The purpose of this chapter is to give the standards to which all streets should be designed and built.
All streets shall conform to the applicable geometric, cross-section, and intersection standards outlined in the Subdivision Regulations and standard drawings, including the design criteria for right of way width, design speed, pavement width, minimum and maximum grades, horizontal and vertical sight distance, cross slope and sidewalk width. Where design criteria are not specified in any locally adopted document, the design standards contained in the AASHTO "Green Book" (A Policy on the Geometric Design of Highways and Streets, 2011 version) shall apply. All newly constructed streets in or adjacent to areas of special flood hazard shall be constructed above the base flood elevation.
All embankments, excavation, grading, stripping, topsoiling, etc., shall be done in accordance with the following specifications.
3.2.1. 
GENERAL. Only materials acceptable to the Engineer shall be used in embankment formation. No frozen material, stumps, logs, roots or other perishable or organic materials shall be placed in any embankment. No stone or masonry fragment greater than 4 inches in any dimension shall be placed within 12 inches of the finished grade elevation.
All excavation, embankment construction, grading and topsoiling shall be accomplished at such places as are indicated on the plans and to the lines, grades and elevations shown on the plans, in the specifications or as directed by the Engineer.
3.2.2. 
EMBANKMENT CONSTRUCTION METHODS. Before embankment placement is begun, all vegetation and rubbish shall be removed from the area within the limits of the embankment. This material shall be disposed of in a method approved by the Engineer.
Embankments shall not be constructed upon frozen areas. All snow and ice shall be removed from the area to be covered prior to placement of embankment material.
Earth embankment shall be formed by distributing the material in successive uniform horizontal layers not exceeding 12 inches in thickness, loose depth, to the full width of the cross section. Each layer of the embankment shall be thoroughly compacted as hereinafter specified. The embankment shall be properly drained at all times.
a. 
Clearing and Grubbing. The developer shall accomplish all clearing and grubbing within the limits designated on the plans or as directed by the Engineer, or as required for the construction of the work involved and shall satisfactorily dispose of all materials so removed.
The work under this paragraph shall consist of cutting and removing all trees, stumps, brush, logs, removal of fences, or other loose or projecting material within the designated areas. Unless otherwise specified, it shall also include the grubbing of stumps, roots, and other natural obstructions which, in the opinion of the Engineer, must be removed to properly prosecute the construction work and properly operate the facility upon completion of construction. Disposal shall be by burning or other methods satisfactory to the Engineer. Trees which are designated to remain shall be properly protected.
b. 
Excavation. This work shall consist of the removal and satisfactory disposal of all materials taken from between the original ground line and the excavation limits approved by the Engineer as shown on the final cross-sections.
All materials encountered, of whatever nature, within the limits designated shall be removed and disposed of as directed. During the process of excavation, the grade shall be maintained in such condition that it will be well drained at all times. When directed, temporary drains and/or drainage ditches shall be installed at the Developer's expense to intercept or divert surface water which may affect the prosecution or condition of the work. If at any time it is not possible to place excavated material in its final location in the permanent construction, it shall be stockpiled in approved areas for later use.
Where rock, shale, clay, hardpan or other unsatisfactory subgrade material is encountered, it shall be excavated to a depth of at least 12 inches, or to such greater depth as the Engineer may direct. The portion so excavated shall be refilled and compacted as set out herein or as specified by the Engineer.
c. 
Embankment Compaction. Place the soil layers to a uniform density not less than 95 percent of maximum density as determined by the Method of ASTM D1557 Modified Proctor.
Should the subgrade lose its density for any reason, it shall be recompacted or replaced as directed by the Engineer. Any area in the subgrade which has yielding or unsuitable material shall be excavated and backfilled with approved material properly compacted as directed by the Engineer.
Breakage and undercutting, including slides in that portion of any material displaced or loosened beyond the limits of the finished work, shall be removed by the developer and disposed of as directed by the Engineer.
3.2.3. 
Grading. Consists of the preparation, shaping, and compaction of that portion of the roadbed upon which aggregate or pavement, including shoulders is to be placed.
a. 
Subgrade Preparation. Shape subgrade to the lines, grades and typical sections shown on the plans. Where the Engineer directs that areas of the subgrade are to be stabilized, the subgrade surface in such areas shall be left uniformly below grade to provide for the addition of stabilizer aggregate. Geotextile, filter fabric, or similar products may also be installed if shown on the plans or required by the Engineer.
Material excavated in preparing the subgrade shall be stored or stockpiled in such manner as to not interfere with proper drainage or any of the subsequent operations of placing base or pavement.
Compaction of subgrade shall be accomplished as set out in the section on "Embankments". The developer shall dry or add moisture to the subgrade to achieve a uniformly compacted and acceptable subgrade and to achieve the specified compaction at or near optimum moisture content as determined by ASTM D 1557 Modified Proctor.
A tolerance of plus or minus 3/4 inch from the established grade will be permitted in the graded, compacted subgrade. No base or pavement construction shall begin on subgrade which has not been inspected and approved by the Engineer.
b. 
Subgrade Drainage. Perforated pipe underdrains shall be required when subgrade conditions warrant, at the discretion of the Engineer. Perforated pipe shall conform to the requirements of Section 704 of the KYTC Standard Specifications. Pipe bedding and backfill shall consist of No. 78, 8 or 9M Coarse aggregate. Perforated pipe shall be a minimum of four inches (4") diameter. Minimum trench width shall be eighteen inches (18"). Provide outlet headwalls or connections to drainage structures conforming to KYTC requirements. See Exhibit 3-2.[1]
When backfilling, place geotextile fabric in the trench and shape to the sides and bottom of the trench without stretching the fabric. Ensure that the geotextile fabric does not pull down into the trench when placing the backfill material. Do not damage the geotextile fabric when placing the filter aggregate. Fold the fabric over the backfilled trench and secure it with steel pins at intervals of 5 feet to produce a double thickness of fabric over the top of the trench.
[1]
Editor's Note: The Exhibits are included as an attachment to this chapter.
c. 
Stabilized Shoulder. Where stabilized shoulder is required (rural-type typical sections without curb and gutter) it shall consist of crushed stone or dense graded aggregate courses equal in depth to the total depth of the adjacent pavement section. Design details shall be as specified by the Engineer, and shall consider traffic and zoning classification of the area.
Base course shall be of Dense Graded Aggregate (DGA) as per the KYTC Standard Specifications, and shall be a minimum of six (6) inches thick after compaction for bituminous concrete pavements. Additional DGA thickness may be required as shown on approved plans.
Number 610 crushed stone or crushed (recycled) concrete may be used in lieu of DGA where permitted by the Engineer. Crushed concrete used as base shall meet grading requirements set by the Engineer, and shall be reasonably free from metal and other deleterious material.
The DGA shall be placed on the prepared subgrade, shaped and compacted to the lines, grades and cross sections shown on the plans or approved by the engineer. It shall have no more than plus or minus 1/2 inch deviation from the typical section after compaction. The base material shall be placed in a manner that produces uniform grades and cross sections satisfactory to the Engineer.
The DGA base shall be compacted to a density of not less than 90% of solid volume throughout the layer. The density determination will be based on the oven-dry bulk specific gravity, ASTM C-127 and the dry weight of the aggregate from the test hole. The in-place density will be determined by the Method of Test for Density of Soil in place by the Rubber-Balloon Method, ASTM D-2167.
All bituminous concrete shall be hot-mixed and hot-laid on a prepared subgrade, old surface or underlying course. The pavement on new construction shall consist of not less than:
Three (3) inches of KYTC Class 2 Asphalt Base, 0.38D PG64-22; and
One (1) inch of KYTC Class 2 Asphalt Surface, 0.38D PG64-22.
3.4.1. 
SPREADING AND FINISHING. All bituminous concrete shall be laid using self-propelled pavers which are capable of spreading and screeding all courses to the indicated widths and depths, true to line, grade and cross section as shown on the plans or directed by the Engineer, with a smooth finish uniform in density and texture. The screed shall be preheated uniformly throughout its length. The paver shall be equipped with hopper and distributing screws of the reversing type that will place the material evenly in front of the screed. Mechanical or electronic devices shall be provided to confine the edge to true line and to adjust the gradeline so than minor changes in subgrade elevation will not be reflected in the finished surface.
A string line shall be used for the first lane of each layer of mixture placed to provide alignment control for the paver, except that a string line will not be required when the first layer is placed adjacent to a curb section.
Pavers shall be equipped with quick and efficient steering mechanism and shall operate at variable speeds consistent with proper placement of materials, but shall not exceed a speed of 50 feet per minute. When placing adjacent lanes of the same course, pavers shall be equipped with a joint matching device which will automatically provide control of the depth of the mixture being placed so that, when compacted, it will match the depth of the existing lane. All paving machines shall be kept in first class mechanical condition.
All bituminous concrete shall be placed at a temperature of not less than 225 degrees F and not more than 300 degrees F. After screeding and before rolling, the surface of each course shall be checked for irregularities and corrected as necessary. In areas where machine paving is impractical, hand spreading is allowed. The material shall be uniformly distributed, without segregation, to the depth necessary to provide the required compacted depth. Rakes may be used, but the final leveling and surface adjustment shall be done with mechanical or manually operated screeds or lutes.
Where new bituminous pavement abuts old, an edge key or other milling may be required by the Engineer to insure a smooth transition between surfaces.
3.4.2. 
COMPACTION. Roll each course as soon as the mixture has cooled sufficiently to bear the weight of the roller without undue displacement. Each paving operation shall have a minimum of the following rollers:
For initial or breakdown rolling on bituminous base course, one tandem steel-wheeled roller weighing not less than ten (10) tons and having a compressive capability at the rear wheels of at least 325 pounds per lineal inch of wheel width.
Provide intermediate rolling of at least 3 complete coverages with a tandem roller weighing at least ten (10) tons. Pneumatic tired rollers may be used when approved by the Engineer.
These rollers shall be in good condition, capable or reversing without backlash. The steel-wheel rollers shall be equipped with wetting devices to prevent the mixture from sticking to the roller wheels.
Perform final rolling of the uppermost layer or surface course with a tandem roller. Operate the roller, at all times, parallel to the centerline. Begin rolling at the sides and progress to the center on crowned surfaces. Begin rolling at the low side and progress to the high side on superelevated sections. Operate the rollers parallel to the centerline, and lap successive trips of each roller uniformly to the previous trip. End alternate trips of the rollers on transverse lines at least 3 feet apart. Regulate starting and stopping of the rollers to avoid distorting the surface.
In areas inaccessible to equipment, the mixture shall be thoroughly compacted by the use of hand tampers or hand operated mechanical tampers.
3.4.3. 
SURFACE TOLERANCE. Final surface shall show no deviation greater than 1/4 inch from a ten (10) foot straight edge placed parallel to the centerline of the street, nor more than 1/4 inch from the typical cross-section.
3.4.4. 
MINIMUM CONSTRUCTION LENGTH. Minimum construction length of street which will be approved to receive bituminous paving shall be 500 feet or the distance between street intersections unless otherwise approved by the Engineer.
Except for streets stubbed out to adjacent property, the subgrade shall be prepared to elevations as shown on the plans for a minimum of 25 feet beyond the end of the base aggregate.
The bituminous base shall be placed no closer than 10 feet from the end of an aggregate base and the bituminous surface no closer than 5 feet from the end of the bituminous base.
3.4.5. 
JOINTS. When the laying of the mixture is to be suspended long enough to permit the mixture to become cool, cut back a distance of one foot (1') or to full-depth asphalt, whichever is greater, to allow correct tie-in to the cold joint. Such joints shall be vertical and in a straight line perpendicular to the course.
At the end of the day construct a sloped wedge ahead of the end of the full depth pavement to provide for proper compaction and protection of the full depth pavement.
When multi-lane, multi-layer construction is required, the width of paving spreads shall be adjusted so as to provide for off-setting of longitudinal joints in the base and surface courses.
3.4.6. 
Weather and seasonal limitations. No bituminous concrete shall be laid when the air temperature is below 40 degrees F, nor when the underlying course is wet, nor when other weather conditions are unsuitable.
No hot-mix bituminous concrete shall be laid between December 1 and April 1, without prior written approval by the Engineer.
Shall consist of a single course, having a minimum depth of at least six (6) inches and shall be constructed on a prepared base in close conformity with the lines, grades and cross-sections shown on the plans, in accordance with the specifications contained herein.
DGA base shall not be required under cement concrete pavement unless warranted by subgrade conditions as deemed necessary by the Engineer. Number 610 crushed stone or crushed (recycled) concrete may be used in lieu of DGA where permitted by the Engineer. Crushed concrete used as base shall meet grading requirements set by the Engineer.
The pavement shall include longitudinal and transverse joints as shown on the plans in accordance with the specifications contained herein. The concrete pavement shall be at least six inches (6") thick and shall consist of Type "P" 4000 psi, air entrained concrete in accordance with the KYTC Standard Specifications.
Perforated pipe underdrains shall be installed parallel to the centerline of the street as shown on the plans in accordance with these specifications.
3.5.1. 
PREPARATION AND CONTROL OF CONCRETE MIXES. Shall be made in accordance with the following specifications and shall meet the approval of the Engineer.
a. 
Batching may be performed at a batch plant, central mix plant, or in truck mixers as approved by the Engineer. All such plants or mixers shall have bins, weighing hoppers, and scales which meet the approval of the Engineer.
b. 
Proportioning. The Engineer shall approve the proportions for the aggregates and water to obtain a satisfactory mix with the required cement content, and no subsequent changes will be permitted except as directed by the Engineer. The concrete mix shall be designed to a six (6) bag mix of cement for each cubic yard produced.
The quantity of fine aggregate shall not be less than 35% nor more than 38% of the total combined solid volumes of the fine and coarse aggregate in a saturated surface dry condition, used in the proportions per bag of cement. The aggregates shall be proportioned to use the maximum percentage of coarse aggregate and the minimum percentage of fine aggregate which will produce a plastic workable mix. When the aggregates are drier than a saturated-surface-dry condition, or when the aggregates contain free moisture, proper adjustments shall be made for aggregate batch weights to compensate for any such conditions.
The maximum free water content in the mix, including the surface moisture in the aggregates, shall not exceed 5.75 gallons per bag of cement.
c. 
Consistency of Concrete. The mixture shall contain no more water than is necessary to produce a workable plastic concrete. The consistency of the concrete shall be continuously uniform and shall be measured in accordance with the "Slump Test" ASTM C-143.
The slump shall not be less than 1-1/2 inches nor more than 2 inches for concrete to be placed without vibration. The slump shall not be more than 1-1/2 inches when the concrete is to be vibrated during placement.
d. 
Air Entrainment. Unless otherwise specified, the required air content of the concrete shall be 6, plus or minus 2, percent by volume. The entrainment of air shall be accomplished by approved methods.
e. 
Strength of Concrete. The minimum strength of concrete pavements at 28 days shall be 4,000 pounds per square inch compressive strength and 500 pounds per square inch modulus of rupture when tested in accordance with methods ASTM C-39 and ASTM C-78, respectively. The Engineer may direct the removal and replacement of sections of the pavement from which the concrete specimens consistently test at low strength. Obtain sample of fresh concrete in accordance with ASTM C-172. Test cylinders for all classes of concrete shall be taken in sets of two, six inch diameter by twelve inch height (6" x 12") cylinders from a composite sample of concrete placed. Cylinders are tested and the average is treated as a single test. Developer shall pay the costs of all applicable testing.
f. 
Hauling Equipment. The concrete shall be transported in truck mixers approved by the Engineer.
g. 
Weather Limitations. Conform to limitations on maximum and minimum mixture and ambient temperatures as per the KYTC Standard Specifications.
3.5.2. 
SUBGRADE AND BASE PREPARATION. Subgrade for Portland cement concrete pavement shall be constructed in accordance with the requirements of Section 3.2.3(a) using an approved machine to produce final subgrade and base surfaces meeting the lines, grades and cross-sections required by the plans.
The surface of the base shall be damp at the time the concrete is placed. The developer shall satisfactorily correct all soft areas in the subgrade or base prior to placing concrete.
Proper protection measures should be taken to prevent disturbance to the subgrade due to hauling over subgrade.
Subgrade underdrains conforming to the requirements of Section 3.2.3 above may be required as directed by the Engineer.
3.5.3. 
FORMING. Forms shall be of such section and design that they will adequately support the concrete and the construction equipment.
All forms shall be inspected and approved by the Engineer or his authorized representative, prior to placement of concrete. Forms shall be straight, free from warp, smooth faced, and of sufficient strength to support the concrete during construction.
The top face of the form shall not vary from a true plane more than 1/8 inch in ten feet. All forms shall be thoroughly oiled before any concrete is placed. Forms shall be set a sufficient distance in advance of the point where the concrete is being placed to provide for a continuous operation in placing the concrete and for proper inspection of line and grade.
Forms shall not be removed from freshly placed concrete until it has hardened sufficiently to resist spalling, cracking or any other damage, but in no case until at least 12 hours after the concrete has been placed. Any honey-combed areas along the sides or edges of the slab shall be repaired by filling with mortar immediately after the forms have been removed. The mortar shall consist of one part cement and two parts fine aggregate.
3.5.4. 
CONCRETE PLACEMENT. Concrete shall be handled in such a manner as to prevent segregation and kept free from mud, soil or any other foreign matter.
Paving operations shall not be undertaken or shall be discontinued when any of the following conditions exist:
a. 
When a descending air temperature in the shade and away from artificial heat reaches 40 degrees F.
b. 
When the subgrade or base course is frozen.
c. 
When aggregates to be used in the mix contain frozen particles.
The mixer and hauling equipment shall not be operated on any new pavement until at least 10 curing days have elapsed. When the mixer is operated on new pavement, the developer shall utilize wood matting or other approved material which will prevent the marking of the pavement and will distribute the load uniformly over the area.
3.5.5. 
SPECIAL DESIGN. Special designs may be required by the Engineer if subsoil condition is not adequate for heavily traveled and industrial roads.
3.5.6. 
SPREADING AND VIBRATING CONCRETE. The concrete shall be spread over the entire area between the forms without segregation. Spreading shall be done with appropriate spreading equipment. After the concrete has been placed, it shall be uniformly vibrated. This vibrating shall be accomplished by approved methods.
3.5.7. 
CONCRETE FINISHING. Finish concrete with approved equipment. Hand finishing will be permitted when the use of mechanical finishing equipment is impractical. The concrete shall be screeded and float finished to the required cross-section and then shall be checked by the use of hand-held, 10 foot straightedges for longitudinal surface uniformity. The final finishing of the pavement shall be accomplished by burlap dragging, brooming or other acceptable methods which produce a similar surface texture. Finish the outside edges and edges of expansion joints with an edging tool having a radius of 1/8 inch.
3.5.8. 
JOINTS. Shall be constructed according to the plans. Joint details shall follow the requirements of the KYTC Standard Specifications and Standard Drawings, with the exception that deformed tie bars shall be required only on transverse joints on collector and arterial streets.
a. 
Transverse Contraction Joints. Shall be formed by an approved joint tool or by sawing with an approved concrete saw.
Where transverse contraction joints are to be sawed, approved joint filler shall be placed at intervals to control random cracking. Sawing shall be done as soon as the concrete has hardened sufficiently to be sawed without spalling and raveling, usually 6 to 24 hours after placing and before shrinkage cracking occurs.
Transverse contraction joints shall be constructed at 20 foot intervals unless otherwise shown on the plans. Where the pavement is constructed adjacent to an existing concrete pavement, joints shall be placed to match the existing joints.
b. 
Longitudinal Contraction Joints. Shall be constructed in all pavements wider than 20 feet in accordance with the details and dimensions shown on the plans, and shall be formed by an approved joint insert or by an approved concrete saw.
When a joint insert is used, the alignment of the finished joint shall be parallel with the center line of the pavement and shall be free from local irregularities in alignment.
Where longitudinal contraction joints are sawed, sawing shall be done as soon as the concrete has hardened sufficiently to be sawed without spalling and raveling, but not more than two (2) days after the concrete is placed.
c. 
Transverse Construction Joints. Shall be constructed at the end of each day's operation (planned joint) or whenever the placing of concrete is suspended for more than 30 minutes (emergency joint). The joints shall be formed by placing an approved header shaped to fit the pavement typical section which forms a vertical face on the end of the pavement, and perpendicular to the pavement section.
Reinforcing steel tie bars shall be required at transverse construction joints on collector streets and arterials, and shall be epoxy coated. The header shall be designed to permit the placement of tie or dowel bars, where required, and shall hold such bars in their correct locations, in accordance with the joint detail drawings contained in the approved plans.
Planned transverse construction joints shall be located at the same spacing required for transverse contraction joints.
The spacing of contraction joints shall not be changed due to emergency construction joints and the emergency construction joint shall not be located within three (3) feet of a contraction joint.
d. 
Longitudinal Construction Joints. Where necessary, shall be constructed in accordance with the joint detail drawings contained in the approved plans.
e. 
Transverse Expansion Joints. Shall be constructed in accordance with the joint detail drawings contained in the approved plans.
f. 
Sealing of Joints. The concrete shall be at least three (3) days old before the joint is sealed. Joints shall be sealed as soon after this three day period as possible, and before any traffic is allowed on the pavement. The joint shall be thoroughly cleaned and dry before sealing.
When the joints have dried, they shall be filled to within approximately 1/8 inch of the surface of the pavement with joint sealer. Care shall be taken in handling the nozzle of the application equipment so that the joint will be filled from the bottom up. Any sealer spilled on the surface of the concrete shall be removed immediately.
A pre-molded insert may be used to seal joints where shown on the plans.
3.5.9. 
CURING CONCRETE. Immediately after finishing operations have been completed and surface water has disappeared, all exposed surfaces of the pavement shall be cured by one of the following methods.
The total curing period shall be a minimum of three (3) days for all methods.
a. 
Liquid Membrane Curing Compounds. The minimum rate of application shall be one (1) gallon per 200 square feet when the application equipment is mechanically operated or one (1) gallon per 150 square feet when the application equipment is hand operated.
b. 
Polyethylene Film. The sections of the film shall be spread in such a manner which will prevent damage to the finished pavement surface. Lap joints of the sections will be at least 12 inches wide and suitable precaution shall be taken to prevent the circulation of air beneath the film.
c. 
Burlap. The sections of the burlap shall be spread in such a manner which will prevent damage to the finished pavement surface. Lap joints will be at least 6 inches wide.
The burlap shall be thoroughly saturated prior to placing on the concrete and shall be kept thoroughly wet throughout the curing period.
3.5.10. 
PROTECTION FROM COLD WEATHER AND RAIN. Concrete less than 72 hours old, which may be subject to damage by freezing, shall be adequately protected by insulation or heating until the concrete reaches an age of 72 hours. Concrete damaged as a result of freezing shall be removed and replaced at the expense of the developer.
Protective coverings which will protect the surface of freshly placed pavement from rain shall be readily available at the site of the work. An adequate quantity of other materials shall be stored at the paving train. Concrete damaged as a result of failure on the part of the developer to adequately protect the concrete from rain shall be repaired or removed and replaced at the expense of the developer.
3.5.11. 
FINAL SURFACE TESTING. As soon as the concrete has set sufficiently to permit walking on it without marring the surface, it shall be tested by the contractor in the presence of the Engineer along the center point and the quarter points of the pavement with a rolling straightedge furnished by the contractor.
The rolling straightedge (profilograph) shall be 10 feet in length between the centers of the wheels. It shall be so designed, constructed and adjusted so that it will adequately indicate and mark all pavement areas which deviate from a plan surface by more than 1/4 inch in 10 feet. The rolling straightedge shall be of a design approved by the engineer.
All deviations more than 1/4 inch in 10 feet marked by the straightedge shall be corrected to within this tolerance by being rubbed or ground down and refinished, or shall be replaced if directed by the Engineer.