824 - CONCRETE SIDEWALK, STEPS AND RAMPS
800-68 e. Sidewalk Ramps with Detectable Warning St rips Compliant with PROWAG – New Construction.
1.Paving Brick. Set the truncated dome paving bricks in a mortar bed as detailed in the Contract Documents. Construct the surface of truncated dome paving brick between the truncated domes flush with the adjacent sidewalk ramp surface. Fill the joints betwee n the truncated dome paving bricks with broomed-in mortar sand. The Engineer will check th e completed truncated dome paving brick surfaces with a 10-foot straightedge. The completed paving brick surfaces may not deviate more than ⅜ inch, unless the contour of the area exceeds this tolerance.
2.Cast-In-Place Prestressed Panels. Prior to the concrete achieving initial set, recess areas to receive prestressed panels below finished grade at locations shown in the Contract Documents. Use a wood float or tool recommended by the manufacturer to achie ve the proper depth and refinish the disturbed area. Prior to placement, pre-dampen the back side of the panel with clean water. Follow the manufacturer’s recommendations for preparing the panel when mortar is specified between the panel and fresh concrete. Install the panels immediately in r ecess areas of fresh concrete and lightly tap the panels to grade using a rubber mallet to establish bond and 100% surface contact. Square the edge s of the panels to provide a symmetrical alignment. Set the depth flush with the adjacent surfaces . Keep the tolerances between panels and surrounding surfaces within 1/16 inch. Maintain a 3/16 inch caulk joint between panels and seal with a Type NS silicon joint sealant. Edge around the panels as shown in the Contract Documents. Clean any concrete residue off of the panels with a damp sponge to provide a clean appearance. Protect the panels from concrete curing compound overspray.
3.Hardened Concrete Placement of Prestressed Panels. Recess the area 3/16 inch more than the thickness of the prestressed panels. Clean the surfaces of all dust, o il, grease, curing or sealing compounds, laitance or other surface contaminants. Mechanically abrade the concre te surface to provide a smooth surface profile. Fill cracks or voids with compounds that are approved by the panel manufacturer. Remove any high spots on the substrate by mechanical methods. Cut a large enough opening to permit expansion joints, when applicable. Install panels with a high-strengt h polymer modified concrete accordin g to the manufacturer’s installation instructions.
4.Cast-In-Place Composite Panels. Install accordi ng to the manufacturer’s in structions. Provide a manufacturer’s representative on site to instruct the Cont ractor and KDOT personnel in the correction installation procedures for the composite panels used. Prior to the concrete achieving initial set, finish th e concrete and recess areas to receive the composite panels below finished grade according to the manufacturer’s instructions. Use a wood float or tool recommended by the manufacturer to achieve the proper depth, and refinish the disturbed area. When possible, install a single, standard size panel large enough to comply with the length and width requirements in the Contract Documents. If installation of a single panel will not satisfy the dimensiona l requirements in the Contract Documents, arrange the installation of standard size panels so the total joint length and panel cutting is minimized. Cut only those prequalified panels listed as used for “all applications”. When cutting panels, utilize auxiliary anchor points, as recommended by the panel manufacturer. Select enough additional anchor points so that no anchor is more than 5 inches from the edge (measured perpendicular to the nearest edge) and adjacent anchors are no more than 24 inches apart.
f.Sidewalk Ramps (Detectable Warning). Construct the detectable warning section on an existing sidewalk ramp, according to the manufacturer’s instructions and this specification, including subsection 824.3e . Construct according to slopes and tolerances in the Cont ract Documents. Perform any necessary sidewalk ramp removal required to construct the detectable warning, without damaging the subgrade or sub-base. Install any necessary Grade 3.0 concrete required to construct the detectable warning. Properly dispose of all waste material, and l eave the area in a neat presentable condition.
g.Curing. Immediately after the finish ing operation, cure the sidewalk, ramps and steps according to
Division 700
h.Contraction, Construction and Expansion Joints. Form contraction joints at intervals shown in the Contract Documents. If not shown, form by placing a metal template having a minimum thickness of ⅛ inch into 824 - CONCRETE SIDEWALK, STEPS AND RAMPS
800-69 the concrete a minimum of ⅓ of the depth of the concrete, or by cutting entirely through the fresh concrete with a
trowel. Construct expansion joints as shown in the Contract Documents. Form construction joints around all appurtenances such as manholes, utili ty poles, etc., extending into and through the sidewalk, and install ¼ inch Type B preformed join t filler in these joints. Install expansion joint filler of the thickness shown in the Contract Documents between concrete sidewalks and any fixed structures such as a building or bridge. Extend the joint filler or expansion joint material for the full depth of the walk. Round the edges of contraction, construction and expansion joints with a ¼ inch radius edging tool.
i.Backfilling. Backfill the area adjacent to new sidewalks, ramps or steps and satisfactorily compact with suitable material. Observe adequate precautions to prevent damage to the sidewalks, ramps or steps during the compacting operations. Dispose of excess excavated material as shown in the Contract Documents or as directed by the Engineer. 824.4 MEASUREMENT AND PAYMENT Excavation for the construction of sidewalks, ramps an d steps will not be measured separately for payment, but will be considered subsidiary work, except when such excavation may be considered as a part of, and may be measured in conjunction with the embankment excavation. In such instances, the excavation will be included in the quantity of embankment excavation com puted as a line item on the contract. The Engineer will measure sidewalk and sidewalk ramps by the square yard of the various thickness indicated. The Engineer will measure sidewalk ramp (detectable warning) by the square yard when it is a bid item in the contract. When sidewalk ramp (detectable warning) is not a bid item in the contract, the work is subsidiary to the bid item sidewalk ramp. The Engineer will measure steps by th e cubic yard of Grade 3.0 concrete. The Engineer will measure reinforcement by the pound according to SECTION 711 . Payment for "Sidewalk Construction", "Sidewalk Ramp", "Grade 3.0 Concrete" and "Reinforcing Steel" at the contract unit prices is full co mpensation for the specified work. Payment for "Sidewalk Ramp (Detectab le Warning)" at the contract set unit price includes all excavation, compaction of subgrade or subbase if required, removal of sidewalk ramp, concrete construction, disposal of waste material, and all material, labor, equipment, tools, supplie s, incidentals and mobilization necessary to complete the work. 825 - CURB AND GUTTER
800-70 Section 825
CURB AND GUTTER 825.1 DESCRIPTION Construct concrete curb and gutter as shown in the Contract Documents. Repair curb as designated in the Contract Documents, or as directed by the Engineer. B I D I T E M S U N I T S Curb, Edge (*) (**) Linear Foot C u r b , H e a d e r ( * * ) L i n e a r F o o t Curb and Gutter, Combined (**) Linear Foot G u t t e r s ( * * ) L i n e a r F o o t Curb, Protection (*) (**) Linear Foot Curb, Asphaltic Concrete Linear Foot Gutters, Asphaltic Concrete Linear Foot Curb and Gutters, Asphaltic Concrete Linear Foot C u r b R e p a i r L i n e a r F o o t *Size, height or special. **"AE" denotes air-entrained concrete. No entry denotes concrete without air. 825.2 MATERIALS Provide materials that comply w ith the applicable requirements. Concrete ................................................................................................................ SECTIONS 401 & 403 Aggregates for On Grade Concrete ....................................................................... SECTION 1116 HMA ..................................................................................................................... DIVISION 600 Reinforcing Steel ................................................................................................... DIVISION 1600 Structural Steel ...................................................................................................... DIVISION 1600 Expansion Join t Filler ............................................................................................ DIVISION 1500 Joint Sealing Compound ....................................................................................... DIVISION 1500 Asphalt Mate rials .................................................................................................. DIVISION 1200 Concrete Surface Re pair-Shotcrete .............................................................................. SECTION 826 Type I or II cement may be used in curb repair concrete. Unless shown otherwise in the Contract Documents, the ag gregate to be used for asphaltic curbs, shall be of the same type as that used on the other bid items in the contract. If there are no other asphalt bid items designated in the Contract Documents, us e Commercial Grade HMA Type A or B. Ad just the maximum sizes and gradation of the aggregate and the asphalt content of the mixture to produce a dense workable mix, capable of being molded, pressed through the slip form without tearing or pulling, and produce a de nse section with smooth and uniform surfaces free from segregated areas and with clear-cut corners and edges. 825.3 CONSTRUCTION REQUIREMENTS
a.Subgrade. Excavate the subgrade for combined curb and gutter, gutters and protection curb as shown in the Contract Documents. If the section is not shown, excavate to the curb and gutter width plus 12 inches on each side. Compact to uniform density. Excavate rock, shale or soft and yielding material 6 inches below subgrade elevation and replace with suitable back fill material. Compact the backf ill material to Type A Compaction, SECTION 205 . Roll and compact the subgrad e to provide a smooth surface.
b.Concrete.
1.Composition, Consistency, Proportioning and Mixing. Unless shown otherwise in the Contract Documents, construct edge curb, header curb, combined curb an d gutter, gutters and protection curb adjacent to 825 - CURB AND GUTTER
800-71 concrete pavement using the grade of concrete specified for the pavement. When concrete curbs are shown to be
adjacent to asphalt pavement construct concrete curb an d gutters, use and place Grade 3.0 concrete as shown in
Division 400
2.Forms. Use steel forms for edge curb or head er curb placed monolithic with concrete pavement. Construct all other types of curb and gutter using steel forms, except, wood may be used for curb or gutter of unusual section or when small quantities are involved, as approved by the Engineer. Use and install forms that will remain true to line and grade. Cl ean and oil forms before each use. Use slip form equipment on a satisfactory performance basis and approved by the Engineer.
3.Reinforcement. Hold reinforcement in the position shown in the Contract Documents by pins, bar chairs or other approved devices. (4) Expansion. Construct contraction and construction joints for curb and gutter as shown in the Contract Documents. Provide joints and materials of the type and complying with the dimensions shown in the Contract Documents. Construct planes of weakness in curbs and gutters at locations shown in the Contract Documents.
5.Placing Concrete. Place concrete according to DIVISION 400 . Construct edge curb and header curb monolithic with concrete pavement. At locations to be covered with curb, clean all laitance and roughen immediately after finishing. Place and un iformly consolidate concrete without vo ids, shape with a steel tool to the dimensions shown in the Contract Documents. Moisten the subgrade before placing concrete for non-monolithic curbs and gutters. Consolidate the concrete with an approved internal type vibrator or by hand spudding and tamping. Shape the surface with a steel tool shaped to produce the cross section shown in the Contract Documents. Use edgers to round the edges to the designated radii.
6.Finish. Finish the surfaces of curbs and gutters with a wood fl oat, unless the Contract Documents specifically require a steel trowel or rubbed finish. Light brushing may be required by the Engineer. (7) Cure. Cure curbs and gutters that are monolith ic with concrete pavement in the same manner as specified for the pavement. Cure all other curbs, gutters and co mbined curb and gutters immediately after the concrete is finished and hardened sufficiently to prevent detrimental marring, according to DIVISION 700 .
c.Asphalt. Clean all foreign material from the surface on which curbs and gutters are to be constructed. When placed on an asphalt surface, apply an asphalt t ack coat as shown in the Contract Documents. Form and compact the sections using an automatic m echanical placing machine, ex cept in extremely short radii or through inaccessible areas. Wh en hand placement methods are necessa ry, form and compact the sections with hand tools and back forms. The maximum temperature of the asphaltic mixture at the time of placement is 335ºF. The minimum temperature shall be sufficient to allow the material to be placed and compacted, to the specified density and surface tolerance requirements. When the air temperature is below 50ºF, or the surf ace temperature is below 55ºF, to obtain an adequate bond between the curb and the surface course, heat the upper portion of the surface course by me thods which will not harm the mixture in the surface course. The Engineer will suspend operations any time that adequate bonding of the section to the surface is not being accomplished. Correct any conditions causing the deficient bonding. On gutter sections, apply a surface tr eatment of asphaltic cement in an am ount to waterproof the section.
d.Backfilling. Backfill the area adj acent to curbs and gutters with approved material to the top edges of the curbs and gutters or to the cross-sections shown in the Contract Documents. Pl ace and compact the backfill according to SECTION 204 , except the compaction requirements may be waived where the backfill area falls within the shoulder area which is to be compacted. If the curb and gutter backfill falls within a shoulder or other area which is designated in the Contract Documents to be compacted, backfill the curb and gutter according to the compaction provision for the adjacent material.
e.Curb Repair. Remove old concrete as shown in the Contract Documents, or as directed by the Engineer. Take care to prevent damage to the concrete that is to rema in in place. Dispose of broken concrete as approved by the Engineer. After removing the old concrete in the curb, clean the ex isting reinforcing steel exposed before the concrete is replaced. 825 - CURB AND GUTTER
800-72 Repair any damage to the existing structure due to the negligence on the part of the Contractor at own
expense. Replace using one of the 2 methods shown below:
1.Standard, Conventional Method. Repair concrete by standard, conventional procedures as shown in the Contract Documents. Use Grade 3.0 concrete for repairing curbs unless s hown otherwise in the Contract Documents. Apply concrete adhesive to existing surfaces prior to placing new concrete, as de signated in the Contract Documents.
2.Concrete Surface Repair-Shotcrete Met hod. Repair the concrete, adhering to SECTION 826 . Either the wet mix or dry mix process may be used. 825.4 MEASUREMENT AND PAYMENT Excavation for the construction of the various types of curbs and gutters will not be measured separately for payment, but will be considered subsidiary work, except when such excavation may be considered as a part of, and may be measured in conjunction with the roadway excavation. In such instances, the excavation will be included in the quantity of roadway excavation computed as a line item on the contract according to DIVISION 200 . The Engineer will measure the various types of curbs and gutters, and combination curb and gutter by the linear foot along the face of the curb. Type I and II combined curb and gutter will not be measured separately, but the Engineer will measure together as linear feet of combined curb and gutter. The Engineer will measure gutter by the linear foot along the flowline. The Engineer will not measure asphalt material or aggregate required to construct the work. Payment for "Curb, Edge", "Curb, Header", "Curb and Gutter, Combined", "Gutters", "Curb, Protection", "Curb, Asphaltic Concrete", "Gutters, Asphaltic Concre te", "Curb and Gutters, Asphaltic Concrete" and "Curb Repair" at the contract unit prices is full compensation for the specified work.
Source: Kansas Standard Specifications for State Road and Bridge Construction, 2015 Edition. Pages 559–563 of 978.