+---
+title: Concrete Paving, Curbs, and Sidewalks
+category: Sitework
+toc_depth: 3
+description: >
+ When to use: Site cast-in-place concrete flatwork and pavements for commercial, institutional, and industrial projects, including exterior vehicular pavements (parking stalls, drive lanes, loading and service areas), sidewalks and walkways, curbs and curb-and-gutter (cast-in-place and slip-formed/extruded), integral curbs, concrete aprons and pads at dumpster and loading areas, ADA curb ramps and the detectable warning surfaces at them. Covers subgrade and aggregate base coordination, concrete mixture and durability (air entrainment for freeze-thaw and deicer exposure), slab thickness, reinforcement (welded wire, dowels at construction joints, tie bars at longitudinal joints), jointing (contraction/control sawcutting timing and depth, isolation joints, construction joints) and joint sealing, finishing (broom and optional exposed aggregate), curing and curing compounds, flatwork tolerances, ADA running and cross-slope limits for walks and ramps, and cold- and hot-weather concreting. Intended to be read alongside the civil grading and paving drawings and the geotechnical report, which govern the pavement section, thicknesses, limits, grades, jointing plan, and drainage.
+ Not intended for: Hot-mix asphalt flexible pavement (see [[syncs/asphalt-paving]]); structural building slabs-on-grade and floors inside the building line (see [[syncs/cast-in-place-concrete]]); equipment foundations and machine pads (see [[syncs/concrete-pads]]); the aggregate base course and subbase beneath the concrete section (see [[syncs/aggregate-base-course]]); subgrade preparation, mass grading, structural fill, and proof rolling (see [[syncs/earthwork]]); storm drainage piping, inlets, and pavement underdrains (see [[syncs/storm-drainage]]); pervious (porous) concrete as the primary pavement system (it uses an open-graded, no-fines mixture not compacted or finished to the criteria of this standard, and requires a separate specification, although it may be selected as an option here); pavement markings and striping on the finished concrete (see [[syncs/pavement-markings]]); and highway, street, and airfield concrete pavement governed by state DOT or FAA specifications, although those documents are referenced herein as accepted industry practice.
+---
+
+# Scope {toc}
+
+## This standard covers the materials, mixture and durability requirements, jointing, finishing, curing, execution, and quality control for site cast-in-place concrete paving, curbs, and sidewalks placed on a prepared subgrade or aggregate base. {note}
+## Site concrete flatwork includes the exterior vehicular pavements a project drives and parks on, the sidewalks and walkways pedestrians use, the curbs and curb-and-gutter that contain and drain the pavement, and the ADA curb ramps that connect the two, all of which share one material and one set of failure modes even though they carry very different loads. {note}
+## Concrete pavement is a rigid system: unlike flexible asphalt, a concrete slab carries wheel loads in flexure and distributes them over a wide area of the support beneath it, so the slab's own flexural strength and its jointing, not the strength of the base, govern most of its performance. {note}
+## The recurring failures of site concrete are not strength failures but durability and detailing failures: random cracking from contraction joints sawn too late or too shallow, restrained cracking where the slab was not isolated from fixed objects, surface scaling where air entrainment was omitted or deicers were applied too early, and ADA non-compliance where running or cross slopes exceed the legal limits. {note}
+## This standard treats jointing, air entrainment, isolation at fixed objects, and ADA slope compliance as the controlling requirements, because those are the four ways site concrete most often fails or fails inspection. {note}
+
+## This standard addresses exterior vehicular concrete pavement, concrete sidewalks and walkways, cast-in-place and slip-formed curbs and curb-and-gutter, integral curbs cast monolithically with the pavement, concrete aprons and pads at service areas, and the detectable warning surfaces installed at curb ramps. {note}
+
+## All work under this standard shall conform to the pavement section, thicknesses, limits, grades, jointing plan, and drainage shown on the contract drawings and to the recommendations of the geotechnical report.
+
+## Where this standard, the geotechnical report, the contract drawings, and the adopted building code conflict, the more stringent requirement shall govern unless the Engineer of Record directs otherwise in writing.
+
+## The Contractor shall not place concrete pavement on an aggregate base or subgrade that has not been prepared, compacted, and accepted under [[syncs/aggregate-base-course]] and [[syncs/earthwork]].
+
+## The Contractor shall coordinate the subgrade, aggregate base, and subbase beneath the concrete section with [[syncs/aggregate-base-course]] and [[syncs/earthwork]].
+
+## The Contractor shall coordinate joint sealants at isolation, construction, and contraction joints with [[syncs/joint-sealants]].
+
+## The Contractor shall coordinate reinforcing steel, welded wire reinforcement, dowels, and tie bars with [[syncs/concrete-reinforcement]].
+
+## The Contractor shall coordinate pavement markings and striping applied to the finished concrete with [[syncs/pavement-markings]].
+
+## This standard does not govern asphalt pavement, structural building slabs-on-grade inside the building line, equipment pads, or the storm drainage system within the paved area.
+
+# Referenced Standards {toc}
+
+## Materials, mixture design, testing, and execution shall comply with the latest adopted edition of the following standards. {note}
+## Where contract documents, adopted codes, and referenced standards conflict, the more stringent requirement shall govern unless the Engineer of Record directs otherwise in writing.
+
+| Standard | Title |
+|----------|-------|
+| ACI PRC-330-21 | Commercial Concrete Parking Lots and Site Paving Design and Construction (Guide) |
+| ACI 330.2R-17 | Guide for the Design and Construction of Concrete Site Paving for Heavy Industrial and Trucking Facilities |
+| ACI 301-20 | Specifications for Concrete Construction |
+| ACI CODE-318-19 | Building Code Requirements for Structural Concrete (durability and exposure classes) |
+| ACI PRC-302.1-15 | Guide to Concrete Floor and Slab Construction (flatwork finishing and tolerances, applied to exterior flatwork) |
+| ACI PRC-305-20 | Guide to Hot Weather Concreting |
+| ACI PRC-306-16 | Guide to Cold Weather Concreting |
+| ASTM C94/C94M | Standard Specification for Ready-Mixed Concrete |
+| ASTM C150/C150M | Standard Specification for Portland Cement |
+| ASTM C595/C595M | Standard Specification for Blended Hydraulic Cements |
+| ASTM C33/C33M | Standard Specification for Concrete Aggregates |
+| ASTM C260/C260M | Standard Specification for Air-Entraining Admixtures for Concrete |
+| ASTM C494/C494M | Standard Specification for Chemical Admixtures for Concrete |
+| ASTM C309 | Standard Specification for Liquid Membrane-Forming Compounds for Curing Concrete |
+| ASTM C1315 | Standard Specification for Liquid Membrane-Forming Compounds Having Special Properties for Curing and Sealing Concrete |
+| ASTM C171 | Standard Specification for Sheet Materials for Curing Concrete |
+| ASTM C143/C143M | Standard Test Method for Slump of Hydraulic-Cement Concrete |
+| ASTM C231/C231M | Standard Test Method for Air Content of Freshly Mixed Concrete by the Pressure Method |
+| ASTM C172/C172M | Standard Practice for Sampling Freshly Mixed Concrete |
+| ASTM C31/C31M | Standard Practice for Making and Curing Concrete Test Specimens in the Field |
+| ASTM C39/C39M | Standard Test Method for Compressive Strength of Cylindrical Concrete Specimens |
+| ASTM C42/C42M | Standard Test Method for Obtaining and Testing Drilled Cores and Sawed Beams of Concrete |
+| ASTM A615/A615M | Standard Specification for Deformed and Plain Carbon-Steel Bars for Concrete Reinforcement |
+| ASTM A1064/A1064M | Standard Specification for Carbon-Steel Wire and Welded Wire Reinforcement, Plain and Deformed, for Concrete |
+| ASTM A1078/A1078M | Standard Specification for Epoxy-Coated Steel Dowels for Concrete Pavements |
+| ASTM A775/A775M | Standard Specification for Epoxy-Coated Steel Reinforcing Bars |
+| ASTM D1751 | Standard Specification for Preformed Expansion Joint Filler for Concrete Paving and Structural Construction (Nonextruding and Resilient Bituminous Types) |
+| ASTM D1752 | Standard Specification for Preformed Sponge Rubber, Cork, and Recycled PVC Expansion Joint Fillers for Concrete Paving and Structural Construction |
+| ADA Standards for Accessible Design (2010) | Americans with Disabilities Act Standards for Accessible Design (accessible route and curb ramp requirements) |
+| PROWAG (2023) | Accessibility Guidelines for Pedestrian Facilities in the Public Right-of-Way (US Access Board final rule, effective 2023) |
+
+### The specific edition of the ADA Standards, PROWAG, and any state or local accessibility code that applies to the project shall be confirmed with the Authority Having Jurisdiction, because pedestrian accessibility is enforced by the AHJ and the applicable edition governs the legal slope and detectable-warning requirements. {note}
+
+### State Department of Transportation standard specifications and standard drawings for concrete curb, gutter, sidewalk, and curb ramp are referenced as accepted industry practice where the project connects to or matches public infrastructure. {note}
+
+# Submittals {toc}
+
+## Action Submittals {toc}
+
+### The Contractor shall submit the following for the Engineer of Record's review before delivering any concrete to the site:
+
+- Concrete mixture design (job-mix) for each class of concrete and each pavement use, showing the cement type and content, supplementary cementitious materials and their proportions, water-cementitious materials ratio, nominal maximum aggregate size, design air content and the freeze-thaw exposure class it satisfies, slump, admixtures, and the specified 28-day compressive or flexural strength
+- Material certifications for the cement (ASTM C150 or C595), aggregates (ASTM C33), air-entraining admixture (ASTM C260), and chemical admixtures (ASTM C494)
+- Product data for the curing compound (ASTM C309 or C1315), including type and class and the application rate
+- Product data for reinforcement: welded wire reinforcement (ASTM A1064), reinforcing bars (ASTM A615), dowels (ASTM A1078 epoxy-coated smooth dowels) and dowel baskets, and tie bars
+- Product data for the preformed isolation/expansion joint filler (ASTM D1751 or D1752) and for the joint sealant, coordinated with [[syncs/joint-sealants]]
+- Product data for the detectable warning surface units at curb ramps, including the truncated-dome geometry and the attachment method
+- Jointing plan (joint layout drawing) showing the location and type of every isolation, construction, and contraction joint, the panel dimensions, and the joint depths, where the jointing is not fully fixed by the contract drawings
+
+```datasheet
+label: Action Submittals Required
+type: checkbox
+options:
+ - "Concrete mixture design(s) with air content and exposure class"
+ - "Material certifications (cement, aggregate, air-entraining and chemical admixtures)"
+ - "Curing compound product data (ASTM C309 / C1315)"
+ - "Reinforcement product data (WWR, bars, dowels and baskets, tie bars)"
+ - "Isolation/expansion joint filler and joint sealant product data"
+ - "Detectable warning surface product data (truncated domes)"
+ - "Jointing plan (joint layout, panel sizes, joint depths)"
+default: "Concrete mixture design(s) with air content and exposure class"
+```
+
+### Concrete placement shall not begin until the submittals are reviewed and returned.
+
+### Submittal review does not relieve the Contractor of responsibility for compliance with the contract documents and the referenced standards.
+
+## Closeout Submittals {toc}
+
+### Prior to substantial completion the Contractor shall provide the following:
+
+- Concrete delivery tickets and field test reports for slump, air content, temperature, and compressive (or flexural) strength, indexed to the placement date, location, and mixture
+- As-built record of finished pavement and walkway surface grades, cross slopes, and curb ramp running and cross slopes sufficient to confirm ADA and drainage compliance
+- Documentation of the jointing as constructed, including any deviations from the approved jointing plan
+- Curing records showing the curing method, the date and time curing began relative to finishing, and the curing duration for each placement
+- Manufacturer's and Contractor's warranty documentation as required by this standard
+
+```datasheet
+label: Closeout Submittals Required
+type: checkbox
+options:
+ - "Delivery tickets and field test reports (slump, air, temperature, strength)"
+ - "As-built surface grades, cross slopes, and curb ramp slopes"
+ - "As-constructed jointing documentation and deviations"
+ - "Curing records (method, start time, duration)"
+ - "Manufacturer's and Contractor's warranty documentation"
+default: ["Delivery tickets and field test reports (slump, air, temperature, strength)", "As-built surface grades, cross slopes, and curb ramp slopes", "Curing records (method, start time, duration)"]
+```
+
+# Quality Assurance {toc}
+
+## Ready-Mix Producer Qualifications {toc}
+
+### The concrete shall be supplied by a ready-mix producer with a current quality-control program and the capability to deliver the specified mixture, air content, and temperature consistently to the site within the ASTM C94 discharge time limit.
+
+```datasheet
+label: Ready-Mix Producer Qualification Basis
+type: radio
+options:
+ - "NRMCA-certified plant (or state DOT plant certification)"
+ - "Producer quality-control program submitted and approved by Engineer of Record"
+ - "Per local Authority Having Jurisdiction certification program"
+default: "NRMCA-certified plant (or state DOT plant certification)"
+```
+
+### The producer shall deliver each load with a delivery ticket showing the mixture identification, batch time, water added, and quantities, as required by ASTM C94.
+
+### Concrete shall be discharged within the time and revolution limits of ASTM C94, and water shall not be added at the site beyond the amount that keeps the mixture within the approved water-cementitious materials ratio. {note}
+
+## Independent Testing Agency {toc}
+
+### Acceptance testing for slump, air content, temperature, and strength shall be performed by a qualified independent testing agency retained by the Owner.
+
+```datasheet
+label: Acceptance Testing Agency — Retained By
+type: radio
+options:
+ - "Owner-retained testing agency (independent of Contractor)"
+ - "Contractor-retained agency with Owner approval — non-structural areas only"
+default: "Owner-retained testing agency (independent of Contractor)"
+```
+
+### Testing for acceptance shall not be performed by the Contractor or by an agency under the Contractor's direction, because the testing entity must be independent of the party whose work it accepts. {note}
+
+### The testing technician shall be certified for the field tests performed (slump, air, temperature, and specimen casting), and the laboratory shall be accredited for the strength tests.
+
+## Mock-Up and Sample Panel {toc}
+
+### Where an exposed aggregate finish, a special broom texture, an integral color, or a stamped pattern is specified, the Contractor shall place a sample panel for the Engineer of Record's approval before placing the corresponding work.
+
+```datasheet
+label: Sample Panel Required
+type: radio
+options:
+ - "Required — exposed aggregate, special texture, integral color, or stamped finish"
+ - "Not required — standard broom finish only"
+default: "Not required — standard broom finish only"
+```
+
+### The approved sample panel shall establish the standard of finish, texture, and color for the work and shall be maintained on site until the corresponding work is accepted.
+
+## Pre-Construction Conference {toc}
+
+### Before paving begins the Contractor shall participate in a pre-construction conference attended by the Contractor's concrete superintendent, the finishing crew foreman, the ready-mix producer's representative, the testing agency, and the Engineer of Record.
+
+### The conference shall review the approved mixture designs and air content, the jointing plan and sawcutting timing, the curing method and timing, the ADA slope requirements and how they will be verified, the hot- and cold-weather provisions, the finishing standard, and the procedure for handling failing test results.
+
+# Environmental and Service Conditions {toc}
+
+## Freeze-Thaw and Deicer Exposure {toc}
+
+### The single most consequential durability decision for site concrete is the freeze-thaw exposure class, because it sets the required air content and the water-cementitious materials limit, and concrete placed without adequate entrained air scales and disintegrates at the surface within a few winters of deicer use. {note}
+### ACI 318 classifies freeze-thaw exposure as F0 (no exposure), F1 (freezing and thawing with limited contact with water), F2 (frequent contact with water), and F3 (freezing and thawing with exposure to water and deicing chemicals), with the required air content rising and the maximum water-cementitious ratio falling as the class becomes more severe. {note}
+### Most exterior site pavement, curb, and sidewalk in a freezing climate is Exposure Class F3, because it is exposed to water and to deicing chemicals, whether applied directly or tracked from vehicles. {note}
+
+```datasheet
+label: Freeze-Thaw / Deicer Exposure Class (ACI 318)
+type: radio
+options:
+ - "F3 — freezing/thawing with water and deicing chemicals (most exterior pavement in freezing climates)"
+ - "F2 — freezing/thawing with frequent water contact, no deicers"
+ - "F1 — freezing/thawing with limited water contact"
+ - "F0 — no freezing-and-thawing exposure (non-freezing climates)"
+default: "F3 — freezing/thawing with water and deicing chemicals (most exterior pavement in freezing climates)"
+```
+
+### Concrete in Exposure Class F1, F2, or F3 shall be air-entrained to the air content required for that class and the nominal maximum aggregate size.
+
+### Concrete in Exposure Class F3 shall meet the ACI 318 limits on the quantity of supplementary cementitious materials, because excessive substitution reduces deicer-scaling resistance.
+
+### Deicing chemicals shall not be applied to the concrete during the first winter after placement, because the surface has not fully matured and early deicer exposure is a leading cause of surface scaling. {note}
+
+## Cold Weather Concreting {toc}
+
+### Cold weather, defined by ACI 306 as a period when the air temperature is at or below 40°F or is expected to fall below 40°F during the protection period, slows hydration and threatens the concrete with freezing before it gains enough strength to resist the expansion of freezing water. {note}
+
+```datasheet
+label: Cold Weather Protection Measures
+type: checkbox
+options:
+ - "Heated mixing water and/or aggregates to meet minimum delivery temperature"
+ - "Insulating blankets or enclosures over placed concrete"
+ - "Non-chloride accelerating admixture (ASTM C494 Type C/E)"
+ - "Ground thawing / no placement on frozen subgrade"
+ - "Maintain concrete above 40°F until required strength is reached"
+default: ["Insulating blankets or enclosures over placed concrete", "Maintain concrete above 40°F until required strength is reached"]
+```
+
+### Concrete shall not be placed on a frozen subgrade or base, nor on a subgrade containing frozen material, because the subgrade thaws beneath the slab and creates a soft, settling support that cracks the slab.
+
+### Concrete placed in cold weather shall be delivered, placed, and protected at the minimum temperatures of ACI 306 and maintained above freezing until it has reached the strength required to resist freezing.
+
+### Calcium chloride and admixtures containing chlorides shall not be used to accelerate set where reinforcement, dowels, or tie bars are present, because chlorides corrode embedded steel; a non-chloride accelerator shall be used instead.
+
+## Hot Weather Concreting {toc}
+
+### Hot weather, defined by ACI 305 as any combination of high air temperature, low humidity, wind, and solar radiation that accelerates moisture loss and hydration, causes rapid slump loss, plastic shrinkage cracking, and reduced ultimate strength. {note}
+
+```datasheet
+label: Hot Weather Protection Measures
+type: checkbox
+options:
+ - "Limit concrete delivery temperature (commonly 90°F maximum)"
+ - "Evaporation retarder / fogging to prevent plastic shrinkage cracking"
+ - "Sunshades and wind breaks at the placement"
+ - "Cooled mixing water or ice; chilled aggregates"
+ - "Set-retarding admixture (ASTM C494 Type B/D)"
+ - "Schedule placement for cooler parts of the day"
+default: ["Evaporation retarder / fogging to prevent plastic shrinkage cracking", "Schedule placement for cooler parts of the day"]
+```
+
+### The concrete temperature at delivery shall not exceed the limit established for the project, commonly 90°F, unless the producer demonstrates that a higher temperature mixture meets the strength and durability requirements.
+
+### During hot, dry, or windy conditions the Contractor shall protect the freshly placed concrete against rapid surface drying with an evaporation retarder, fogging, or wind protection, and shall begin curing immediately after finishing, because plastic shrinkage cracking forms within minutes of the surface drying faster than bleed water rises. {note}
+
+# Concrete Materials and Mixture {toc}
+
+## Cement and Supplementary Cementitious Materials {toc}
+
+### Portland cement shall conform to ASTM C150, or blended hydraulic cement shall conform to ASTM C595, of the type appropriate to the exposure and any sulfate condition in the soil.
+
+```datasheet
+label: Cement Type
+type: select
+options:
+ - "ASTM C150 Type I/II (general use, moderate sulfate resistance)"
+ - "ASTM C150 Type II (moderate sulfate resistance)"
+ - "ASTM C150 Type V (high sulfate resistance, aggressive soils)"
+ - "ASTM C595 blended cement (with SCM, general use)"
+default: "ASTM C150 Type I/II (general use, moderate sulfate resistance)"
+```
+
+### Supplementary cementitious materials such as fly ash or slag cement may be used within the proportions of the approved mixture design and within the ACI 318 limits for the applicable freeze-thaw exposure class.
+
+### Where the geotechnical report identifies a sulfate-bearing soil or groundwater, the cement type and the water-cementitious materials ratio shall satisfy the corresponding ACI 318 sulfate exposure class (S1, S2, or S3).
+
+## Aggregates {toc}
+
+### Concrete aggregates shall conform to ASTM C33, clean, well-graded, and durable, with a nominal maximum size suited to the slab thickness and reinforcement spacing.
+
+```datasheet
+label: Nominal Maximum Aggregate Size
+type: select
+unit: in
+options:
+ - "3/4 in. (sidewalks, curbs, thin flatwork)"
+ - "1 in. (typical pavement)"
+ - "1-1/2 in. (thicker heavy-duty pavement)"
+default: "1 in. (typical pavement)"
+```
+
+### Coarse aggregate shall be sound and resistant to freeze-thaw deterioration, because a non-durable (D-cracking-susceptible) aggregate fails the concrete from within regardless of the air content of the paste. {note}
+
+## Air Entrainment {toc}
+
+### Entrained air is the primary defense against freeze-thaw and deicer scaling: the microscopic air bubbles give freezing water somewhere to expand into, relieving the internal pressure that otherwise spalls the surface, and an exterior pavement mixture without adequate entrained air will scale regardless of its strength. {note}
+### Air entrainment is provided by an air-entraining admixture conforming to ASTM C260, and is verified in the field by the pressure method (ASTM C231), not assumed from the mixture design. {note}
+
+```datasheet
+label: Total Air Content (freeze-thaw exposure, 1 in. NMAS)
+type: range
+unit: percent
+options:
+ min: 4.5
+ max: 7.5
+ setpoints: [4.5, 5.5, 6.0, 6.5, 7.5]
+default: 6.0
+```
+
+### Concrete subject to freeze-thaw exposure (Class F1, F2, or F3) shall contain entrained air at the target content for the exposure class and nominal maximum aggregate size, commonly about 6 percent total air for a 1 in. nominal maximum aggregate, within the tolerance of ASTM C94.
+
+### Air content shall be measured at the point of placement at the frequency required by this standard, and concrete outside the specified air range shall be rejected. {note}
+
+## Slump and Water-Cementitious Materials Ratio {toc}
+
+### The water-cementitious materials ratio is the dominant control on both strength and freeze-thaw durability, and adding water at the site to ease placement raises that ratio, weakening the surface exactly where scaling resistance is needed. {note}
+
+```datasheet
+label: Maximum Water-Cementitious Materials Ratio
+type: range
+unit: w/cm by mass
+options:
+ min: 0.40
+ max: 0.50
+ step: 0.01
+default: 0.45
+```
+
+```datasheet
+label: Target Slump at Placement
+type: range
+unit: in
+options:
+ min: 1
+ max: 5
+ step: 0.5
+default: 4
+```
+
+### The water-cementitious materials ratio shall not exceed the maximum for the applicable exposure class, commonly 0.45 by mass for freeze-thaw and deicer exposure (Class F3).
+
+### Slump shall be as required for the placement method, and shall not be increased by adding water beyond the approved mixture; where higher workability is needed, a water-reducing admixture (ASTM C494) shall be used instead.
+
+### Slip-formed curb and slip-formed pavement shall use a lower slump than hand-placed work so the extruded shape holds its edge without slumping.
+
+## Compressive and Flexural Strength {toc}
+
+### Site concrete pavement is designed on flexural strength (modulus of rupture) because it carries load in bending, but it is most commonly specified and accepted on compressive strength for ease of field testing, with a corresponding minimum value. {note}
+
+```datasheet
+label: Specified 28-Day Compressive Strength
+type: select
+unit: psi
+options:
+ - "3500 psi (sidewalks and light-duty flatwork)"
+ - "4000 psi (typical vehicular pavement and curb)"
+ - "4500 psi (heavy-duty and truck pavement)"
+ - "5000 psi (industrial and trucking pavement)"
+default: "4000 psi (typical vehicular pavement and curb)"
+```
+
+```datasheet
+label: Strength Acceptance Basis
+type: radio
+options:
+ - "Compressive strength (ASTM C39) — most common"
+ - "Flexural strength / modulus of rupture (ASTM C78) — where pavement design specifies it"
+default: "Compressive strength (ASTM C39) — most common"
+```
+
+### Concrete shall achieve the specified 28-day compressive strength, commonly 4000 psi for vehicular pavement and curb, as shown on the drawings and the mixture design.
+
+### Where the pavement design specifies flexural strength (modulus of rupture), the mixture shall be qualified and accepted on flexural strength, and the correlation to compressive strength used for field acceptance shall be established with the mixture design.
+
+# Pavement Section and Thickness {toc}
+
+## Concrete pavement is built as a rigid slab on a prepared base, and its thickness is set by the design wheel loads, the concrete flexural strength, and the support beneath it; thinning a slab to economize directly reduces its load capacity because flexural capacity varies with the square of the thickness. {note}
+
+## Pavement Use and Thickness {toc}
+
+### The slab thickness shall be as shown on the pavement section detail and shall not be reduced to compensate for a high base or to economize on material.
+
+```datasheet
+label: Pavement Use Category
+type: select
+options:
+ - "Sidewalk / walkway (pedestrian)"
+ - "Automobile parking stalls (passenger vehicles)"
+ - "Drive lanes / light truck traffic"
+ - "Heavy truck, loading, and service areas"
+ - "Industrial / trucking facility pavement"
+default: "Automobile parking stalls (passenger vehicles)"
+```
+
+```datasheet
+label: Concrete Slab Thickness
+type: range
+unit: in
+drawing_ref: "pavement section detail"
+options:
+ min: 4
+ max: 10
+ setpoints: [4, 5, 6, 7, 8, 9, 10]
+default: 6
+```
+
+### Sidewalks and pedestrian walkways shall be not less than 4 in. thick, increased to 6 in. where the walk is crossed by vehicles such as at a driveway apron.
+
+### Vehicular pavement thickness shall be as established by the pavement design for the traffic category, commonly 5 to 6 in. for automobile parking and 7 to 9 in. for heavy truck and loading areas.
+
+## Subgrade and Base Support {toc}
+
+### The slab is only as good as the support beneath it, and a slab placed on a soft spot or a poorly compacted base cracks where the support is weakest no matter how strong the concrete is. {note}
+
+### The subgrade and aggregate base shall be prepared, compacted, proof-rolled, and accepted under [[syncs/aggregate-base-course]] and [[syncs/earthwork]] before concrete is placed.
+
+### The base shall be at the correct elevation and cross slope within tolerance, uniformly compacted, free of soft spots, and dry and unfrozen at the time of placement.
+
+### The base shall be moistened (not saturated) before placing concrete in hot, dry conditions so that the dry base does not draw water out of the bottom of the slab. {note}
+
+# Reinforcement {toc}
+
+## Plain (Unreinforced) versus Reinforced Pavement {toc}
+
+### Jointed plain concrete pavement, with no distributed reinforcement and load transfer carried by aggregate interlock and dowels at joints, is the standard and most economical site pavement when the contraction joints are spaced closely enough to control cracking; distributed reinforcement is added only where panels are large, slabs are irregular, or crack-width control is required. {note}
+
+```datasheet
+label: Pavement Reinforcement Type
+type: radio
+options:
+ - "Jointed plain (unreinforced) — closely spaced contraction joints (typical pavement)"
+ - "Welded wire reinforcement (WWR) for crack-width control / larger panels"
+ - "Reinforcing bar mat where shown on the drawings"
+default: "Jointed plain (unreinforced) — closely spaced contraction joints (typical pavement)"
+```
+
+### Where distributed reinforcement is omitted (jointed plain pavement), crack control shall be achieved by contraction joint spacing within the limits of this standard.
+
+## Welded Wire and Bar Reinforcement {toc}
+
+### Welded wire reinforcement shall conform to ASTM A1064, and reinforcing bars shall conform to ASTM A615, of the size and spacing shown on the drawings.
+
+```datasheet
+label: Distributed Reinforcement (where used)
+type: select
+drawing_ref: "pavement section detail"
+options:
+ - "Welded wire reinforcement, flat sheets (not rolls)"
+ - "Welded wire reinforcement, deformed (ASTM A1064)"
+ - "Reinforcing bar mat (ASTM A615 Grade 60)"
+default: "Welded wire reinforcement, flat sheets (not rolls)"
+```
+
+### Welded wire reinforcement shall be supplied in flat sheets rather than rolls, because rolled reinforcement springs back and ends up at the bottom of the slab where it does no good. {note}
+
+### Distributed reinforcement shall be positioned and held at the design height in the upper third of the slab on chairs or supports, and shall not be pulled up from the subgrade ("hooking") after the concrete is placed, because hooking leaves the steel at an unknown and ineffective depth. {note}
+
+### Reinforcement shall be lapped, supported, and covered as shown on the drawings and as required by [[syncs/concrete-reinforcement]], with adequate concrete cover for exterior exposure.
+
+## Dowels at Construction Joints {toc}
+
+### Dowels are smooth round bars that span a transverse construction (or contraction) joint to transfer wheel loads across the joint without tying the two slabs together, allowing the joint to open and close while keeping the two slab edges at the same elevation; without load transfer the joint faults, producing a bump and accelerating joint failure. {note}
+
+```datasheet
+label: Load Transfer Dowels at Transverse Joints
+type: radio
+options:
+ - "Required — smooth epoxy-coated dowels (ASTM A1078) on baskets at vehicular pavement joints"
+ - "Required — at heavy-duty and truck pavement joints only"
+ - "Not required — pedestrian sidewalk or aggregate-interlock light pavement"
+default: "Required — smooth epoxy-coated dowels (ASTM A1078) on baskets at vehicular pavement joints"
+```
+
+```datasheet
+label: Dowel Bar Diameter
+type: select
+unit: in
+drawing_ref: "jointing detail"
+options:
+ - "1 in. (5 to 6 in. slabs)"
+ - "1-1/4 in. (6 to 8 in. slabs)"
+ - "1-1/2 in. (8 in. and thicker slabs)"
+default: "1-1/4 in. (6 to 8 in. slabs)"
+```
+
+### Dowels at vehicular pavement transverse construction joints shall be smooth, epoxy-coated round bars conforming to ASTM A1078, of the diameter shown on the jointing detail.
+
+### Dowels shall be installed parallel to the pavement surface and to the direction of traffic, held in alignment by a dowel basket or an approved support, and one half of each dowel length shall be coated with a bond breaker so the joint can open and close. {note}
+
+### Dowels shall be spaced as shown on the jointing detail, commonly at 12 in. on center across the joint.
+
+## Tie Bars at Longitudinal Joints {toc}
+
+### Tie bars are deformed bars that hold adjacent slabs together across a longitudinal joint so the joint stays tightly closed and aggregate interlock is maintained; unlike dowels, tie bars are bonded on both sides and are not intended to permit movement, only to keep lanes from separating. {note}
+
+```datasheet
+label: Tie Bars at Longitudinal Joints
+type: radio
+options:
+ - "Required — deformed tie bars (ASTM A615) across longitudinal joints between lanes/passes"
+ - "Not required — single-width placement with no longitudinal joint"
+default: "Required — deformed tie bars (ASTM A615) across longitudinal joints between lanes/passes"
+```
+
+### Tie bars at longitudinal joints shall be deformed bars conforming to ASTM A615, of the size and spacing shown on the jointing detail, commonly spaced at about 24 in. to 30 in. on center.
+
+### Tie bars shall not be used at transverse contraction or expansion joints, because tying those joints closed prevents the movement they exist to accommodate and forces cracking elsewhere. {note}
+
+# Jointing {toc}
+
+## Jointing is the single most important detailing requirement for site concrete: concrete shrinks as it dries and contracts as it cools, and unless that movement is relieved at planned joints the slab cracks where it chooses, producing the random cracking that is the most common defect in site flatwork. {note}
+## Three joint types do three different jobs: isolation joints separate the slab from fixed objects and adjacent construction so each can move independently; contraction (control) joints create a weakened plane that forces the inevitable shrinkage crack to occur straight and hidden at the joint; and construction joints are the planned stopping points between placements. {note}
+
+## Contraction (Control) Joints {toc}
+
+### Contraction joints are formed by sawing (or tooling) a continuous groove that creates a weakened plane through part of the slab depth, so that as the concrete shrinks it cracks downward beneath the groove rather than randomly across the panel. {note}
+
+```datasheet
+label: Contraction Joint Method
+type: radio
+options:
+ - "Early-entry (dry-cut) saw — cut soon after finishing, before random cracking"
+ - "Conventional wet saw — cut after concrete gains sufficient strength"
+ - "Tooled (hand-grooved) joint — sidewalks and small flatwork"
+default: "Early-entry (dry-cut) saw — cut soon after finishing, before random cracking"
+```
+
+```datasheet
+label: Contraction Joint Depth
+type: radio
+options:
+ - "One-fourth (1/4) of slab thickness — conventional saw or tooled joint"
+ - "1-1/4 in. depth — early-entry (dry-cut) saw, slabs up to ~9 in."
+ - "One-third (1/3) of slab thickness — where required to ensure activation"
+default: "One-fourth (1/4) of slab thickness — conventional saw or tooled joint"
+```
+
+```datasheet
+label: Maximum Contraction Joint Spacing
+type: range
+unit: ft
+drawing_ref: "jointing plan"
+options:
+ min: 8
+ max: 15
+ setpoints: [8, 10, 12, 15]
+default: 12
+```
+
+### Contraction joints shall be sawn to a depth of not less than one-fourth of the slab thickness for conventional wet-cut joints, or to 1-1/4 in. for early-entry dry-cut joints in slabs up to about 9 in. thick, so that the weakened plane reliably activates the crack at the joint. {note}
+
+### Contraction joints shall be sawn as soon as the concrete has hardened enough that the saw does not ravel the edge, and before the concrete has cooled and shrunk enough to crack on its own; sawing too late is the most common cause of random cracking because the slab has already cracked before the joint was cut. {note}
+
+### Contraction joint spacing shall not exceed the spacing on the jointing plan, and as a general guide shall not exceed about 24 to 36 times the slab thickness in inches (expressed in feet), and panels shall be kept as square as practicable, because long, narrow panels crack across their middle.
+
+### Contraction joints shall be continued through any integral curb cast with the pavement and aligned with the pavement joints, because a curb that is not jointed in line with the slab cracks at the unrelieved restraint. {note}
+
+## Isolation (Expansion) Joints {toc}
+
+### Isolation joints separate the new slab from anything that will not move with it: building walls, columns, light pole bases, manholes, catch basins, hydrants, existing pavement, and the back of fixed curbs, so the slab can shrink, expand, and curl without cracking from the restraint of the fixed object. {note}
+### The most common cause of cracking radiating from a manhole, a column, or a light base in the middle of a pavement is a missing isolation joint around that object, and the fix is to detail isolation at every penetration and fixed edge. {note}
+
+```datasheet
+label: Isolation Joint Filler
+type: select
+options:
+ - "Preformed bituminous fiber filler (ASTM D1751)"
+ - "Sponge rubber / cork / recycled PVC filler (ASTM D1752)"
+ - "Closed-cell foam expansion joint filler"
+default: "Preformed bituminous fiber filler (ASTM D1751)"
+```
+
+```datasheet
+label: Isolation Joint Filler Thickness
+type: radio
+unit: in
+options:
+ - "1/2 in."
+ - "3/4 in."
+default: "1/2 in."
+```
+
+### Isolation joints with a full-depth preformed filler conforming to ASTM D1751 or D1752 shall be provided wherever the pavement, walk, or curb abuts a building, a column, a foundation, a fixed structure, an existing pavement, or a utility penetration.
+
+### Isolation joints shall be provided around every fixed object that penetrates or abuts the slab, including manholes, catch basins, light pole bases, hydrants, sign posts, and bollards.
+
+### The preformed filler shall extend the full depth of the slab so no concrete bridges across the joint and locks the slab to the fixed object.
+
+## Construction Joints {toc}
+
+### Construction joints are the planned edges where one placement stops and the next begins, located at a contraction joint line where practicable so the construction joint also serves as a movement joint. {note}
+
+### Construction joints shall be located at planned joint lines shown on the jointing plan, and an unplanned construction joint forced by an interruption (such as a concrete delivery failure) shall be located at the nearest contraction joint line.
+
+### Load transfer across transverse construction joints in vehicular pavement shall be provided by dowels as required by this standard.
+
+## Joint Sealing {toc}
+
+### Sealing the sawn and isolation joints keeps water and incompressible debris out of the joint, protecting the joint from spalling and keeping water from reaching and softening the base; joints in pavement subject to deicers and to traffic are sealed, while many light-duty and pedestrian joints are left unsealed by design. {note}
+
+```datasheet
+label: Joint Sealing
+type: radio
+options:
+ - "Seal contraction and isolation joints (vehicular pavement, deicer exposure)"
+ - "Seal isolation joints only"
+ - "Joints left unsealed (light-duty / pedestrian, where permitted)"
+default: "Seal contraction and isolation joints (vehicular pavement, deicer exposure)"
+```
+
+### Where joints are sealed, the sealant shall be installed over a backer rod or bond breaker so the sealant bonds only to the two joint faces and can stretch as the joint opens, in accordance with [[syncs/joint-sealants]].
+
+### Joints shall be clean and dry before sealing, and the sealant shall be recessed slightly below the surface so traffic does not abrade it.
+
+# Curbs and Curb-and-Gutter {toc}
+
+## Curb Type {toc}
+
+### Curbs contain the pavement edge, direct surface drainage to inlets, and protect adjacent landscaping and walks; curb-and-gutter combines the curb with a flat gutter pan that carries the flow line, and the curb may be cast in forms, slip-formed (extruded) by machine, or cast integrally with the pavement slab. {note}
+
+```datasheet
+label: Curb Type
+type: select
+drawing_ref: "curb detail"
+options:
+ - "Vertical (barrier) curb"
+ - "Curb and gutter (combined)"
+ - "Rolled (mountable) curb"
+ - "Integral curb (cast monolithically with pavement)"
+default: "Curb and gutter (combined)"
+```
+
+```datasheet
+label: Curb Placement Method
+type: radio
+options:
+ - "Slip-formed (machine-extruded)"
+ - "Cast-in-place in forms"
+default: "Slip-formed (machine-extruded)"
+```
+
+### Curb and curb-and-gutter shall be constructed to the shape, dimensions, and flow-line grade shown on the curb detail and the grading plan.
+
+### Slip-formed (extruded) curb shall use a low-slump mixture that holds the extruded shape without slumping or tearing, and the trailing edge shall be finished and cured the same as cast-in-place work.
+
+### Integral curb cast monolithically with the pavement shall be jointed in line with the pavement contraction and isolation joints, because an unrelieved integral curb cracks at every point of restraint.
+
+## Curb Jointing {toc}
+
+### Contraction joints in curb and curb-and-gutter shall be provided at a spacing matching or aligned with the adjacent pavement joints, and isolation joints shall be provided at structures, inlets, and at the ends of curb returns.
+
+```datasheet
+label: Curb Contraction Joint Spacing
+type: range
+unit: ft
+drawing_ref: "curb detail"
+options:
+ min: 6
+ max: 15
+ setpoints: [6, 10, 12, 15]
+default: 10
+```
+
+### Curb returns and short curb segments at radii shall be jointed so that the short, highly restrained pieces are isolated and can move independently.
+
+# Sidewalks and ADA Curb Ramps {toc}
+
+## Sidewalk Geometry and ADA Slopes {toc}
+
+### Sidewalks and walkways that are part of an accessible route are governed by the ADA Standards and, in the public right-of-way, by PROWAG, and the slope limits are not guidelines but legal requirements enforced by the Authority Having Jurisdiction; a walk that exceeds them must be removed and replaced. {note}
+### The two controlling slope limits are the running slope (in the direction of travel), which shall not exceed 1:20 (5 percent) for a walk to remain an accessible route without ramp provisions, and the cross slope (perpendicular to travel), which shall not exceed 1:48 (about 2 percent). {note}
+
+```datasheet
+label: Sidewalk Width
+type: range
+unit: in
+drawing_ref: "site plan"
+options:
+ min: 36
+ max: 120
+ setpoints: [36, 48, 60, 72, 96, 120]
+default: 60
+```
+
+```datasheet
+label: Maximum Walk Cross Slope (ADA)
+type: radio
+options:
+ - "1:48 (2.0 percent) maximum — ADA accessible route"
+ - "Less than 2.0 percent target to provide construction tolerance"
+default: "1:48 (2.0 percent) maximum — ADA accessible route"
+```
+
+```datasheet
+label: Maximum Walk Running Slope (ADA)
+type: radio
+options:
+ - "1:20 (5.0 percent) maximum — accessible route without ramp provisions"
+ - "Follows adjacent roadway grade (public right-of-way, per PROWAG)"
+default: "1:20 (5.0 percent) maximum — accessible route without ramp provisions"
+```
+
+### Sidewalks on an accessible route shall be not less than 36 in. wide clear, and shall be wider where the project, the AHJ, or the use requires.
+
+### The cross slope of an accessible walk shall not exceed 1:48 (2.0 percent), and the Contractor should target a cross slope below the maximum so that construction tolerance does not produce a non-compliant finished slope. {note}
+
+### The running slope of an accessible walk shall not exceed 1:20 (5.0 percent); where the grade must be steeper, the walk becomes a ramp and shall meet the ramp running-slope, landing, and handrail requirements of the ADA Standards.
+
+### The Contractor shall verify the as-built running and cross slopes of every accessible walk and ramp with a level or digital inclinometer before the concrete is accepted, because slope non-compliance discovered after acceptance requires removal and replacement. {note}
+
+## Curb Ramps {toc}
+
+### Curb ramps provide the transition from the sidewalk to the street at crossings, and their running slope, landing, flare, and detectable warning are all regulated; the curb ramp running slope shall not exceed 1:12 (8.33 percent). {note}
+
+```datasheet
+label: Maximum Curb Ramp Running Slope (ADA)
+type: radio
+options:
+ - "1:12 (8.33 percent) maximum running slope"
+ - "Per PROWAG for public right-of-way curb ramps"
+default: "1:12 (8.33 percent) maximum running slope"
+```
+
+### The curb ramp running slope shall not exceed 1:12 (8.33 percent), and the ramp shall provide a level landing at the top within the cross-slope tolerance so a wheelchair user can stop and turn.
+
+### The transition between the curb ramp and the street (the gutter and counter slope) shall be within the ADA limits so that the combined grade break is not a tripping or wheel-catching hazard.
+
+## Detectable Warning Surfaces {toc}
+
+### Detectable warning surfaces are the truncated-dome pattern installed at curb ramps and flush transitions to alert pedestrians with vision impairments to the edge of the vehicular way; the truncated dome is the only detectable warning pattern the ADA recognizes. {note}
+
+```datasheet
+label: Detectable Warning Surface Type
+type: select
+options:
+ - "Cast-in-place replaceable tile / paver (wet-set or mechanically fastened)"
+ - "Surface-applied (retrofit) detectable warning panel"
+ - "Stamped/tooled domes — only where the AHJ accepts them"
+default: "Cast-in-place replaceable tile / paver (wet-set or mechanically fastened)"
+```
+
+```datasheet
+label: Detectable Warning Depth (direction of travel)
+type: radio
+unit: in
+options:
+ - "24 in. deep, full width of the ramp/flush surface (ADA)"
+ - "Per PROWAG for public right-of-way"
+default: "24 in. deep, full width of the ramp/flush surface (ADA)"
+```
+
+### Detectable warning surfaces shall consist of truncated domes conforming to the size, spacing, and contrast requirements of the applicable ADA Standards or PROWAG.
+
+### The detectable warning surface shall extend 24 in. in the direction of travel and the full width of the curb ramp run or flush transition.
+
+### The rows of truncated domes shall be aligned perpendicular to the grade break between the ramp and the street so that a wheelchair user can track between the rows of domes. {note}
+
+### The detectable warning surface shall contrast visually with the adjacent walking surface (light-on-dark or dark-on-light) so it is detectable by pedestrians with low vision.
+
+# Finishing {toc}
+
+## Surface Finish {toc}
+
+### Exterior pavement and walks receive a broom (textured) finish, dragging a broom across the freshly floated surface to create a slip-resistant texture; a smooth steel-troweled finish, standard for interior floors, shall not be used on exterior flatwork because it is dangerously slick when wet or icy. {note}
+
+```datasheet
+label: Surface Finish
+type: select
+options:
+ - "Broom finish, transverse to direction of travel (standard exterior)"
+ - "Exposed aggregate (washed or retarded) — decorative/architectural"
+ - "Light broom over float finish (where a finer texture is shown)"
+ - "Stamped/patterned finish (architectural areas, per sample panel)"
+default: "Broom finish, transverse to direction of travel (standard exterior)"
+```
+
+### Exterior pavement, walks, and curb gutters shall receive a broom finish that provides a slip-resistant surface texture, with the broom strokes run transverse to the direction of travel on walks and ramps.
+
+### A hard steel-troweled (burnished) finish shall not be used on exterior flatwork, because it produces a surface that is slippery when wet or frozen and that traps bleed water beneath a dense skin, increasing scaling. {note}
+
+### Overworking and overtroweling the surface shall be avoided, and finishing shall not be performed while bleed water is present on the surface, because finishing bleed water into the surface weakens it and promotes scaling. {note}
+
+## Exposed Aggregate Finish {toc}
+
+### An exposed aggregate finish, where the surface mortar is washed or chemically retarded and removed to reveal the coarse aggregate, may be specified for architectural areas, and shall be produced to match the approved sample panel.
+
+### Where an exposed aggregate finish is specified, the aggregate selected for exposure shall be durable and uniform in color, and the depth of exposure shall match the approved sample panel uniformly across the work.
+
+## Edging and Tooling {toc}
+
+### Exposed edges of walks, curbs, and slabs shall be tooled to a rounded edge so the brittle arris does not chip under traffic and so the edge sheds water.
+
+# Curing {toc}
+
+## Curing keeps water in the concrete during the early hardening period so that hydration continues and the surface develops its full strength and abrasion and scaling resistance; inadequate curing, especially of exterior flatwork, produces a weak, dusting, scale-prone surface even when the concrete below is sound, and curing is the most frequently shortchanged step in flatwork. {note}
+
+## Curing Method {toc}
+
+### Curing shall begin immediately after final finishing and shall continue for the required duration without interruption.
+
+```datasheet
+label: Curing Method
+type: select
+options:
+ - "Liquid membrane-forming curing compound (ASTM C309)"
+ - "Curing and sealing compound (ASTM C1315) — where a sealer is also desired"
+ - "Wet curing (continuous water / wet burlap / cotton mats)"
+ - "Sheet curing (waterproof paper or polyethylene, ASTM C171)"
+default: "Liquid membrane-forming curing compound (ASTM C309)"
+```
+
+```datasheet
+label: Minimum Curing Duration
+type: range
+unit: days
+options:
+ min: 3
+ max: 7
+ setpoints: [3, 5, 7]
+default: 7
+```
+
+### Where a liquid membrane-forming curing compound is used, it shall conform to ASTM C309, and white-pigmented (Type 2) compound should be used in hot, sunny conditions to reduce solar heat gain at the surface.
+
+### The curing compound shall be applied uniformly at the manufacturer's coverage rate immediately after the surface water sheen has disappeared, in a continuous unbroken membrane, because gaps in the membrane cure unevenly and leave weak streaks. {note}
+
+### Curing shall continue for not less than the required duration, commonly 7 days for exterior flatwork at normal temperatures, extended in cold weather when hydration is slower.
+
+### A curing compound shall not be applied where a bonded topping, sealant, or coating will later be placed, unless the compound is compatible with that material or is removed, because the curing membrane is a bond breaker. {note}
+
+# Tolerances {toc}
+
+## Flatwork Surface Tolerance {toc}
+
+### The finished surface shall be true to the grades and cross slopes shown, checked with a 10-foot straightedge, and shall drain positively to the inlets and gutters without birdbaths that hold water. {note}
+
+```datasheet
+label: Surface Flatness Tolerance (10 ft straightedge)
+type: radio
+options:
+ - "1/4 in. in 10 ft (typical walks and pavement)"
+ - "1/8 in. in 10 ft (where a tighter tolerance is specified)"
+default: "1/4 in. in 10 ft (typical walks and pavement)"
+```
+
+### The finished surface deviation under a 10-foot straightedge shall not exceed 1/4 in., laid in any direction.
+
+### The finished pavement shall drain positively to the gutters and inlets [[drawing: as indicated on the grading and drainage plan]] with no birdbaths that hold water deeper than 1/8 in. after a rain.
+
+## Thickness Tolerance {toc}
+
+### Each slab shall be placed to the thickness shown on the pavement section, verified by cores or by survey, and a deficient slab reduces the load capacity in proportion to the square of the thickness and is not correctable except by removal and replacement. {note}
+
+```datasheet
+label: Slab Thickness Tolerance
+type: radio
+options:
+ - "Minus 1/4 in. to plus 1/2 in. from design thickness"
+ - "Per pavement section detail"
+default: "Minus 1/4 in. to plus 1/2 in. from design thickness"
+```
+
+### Slab thickness shall not be deficient by more than 1/4 in. below the design thickness, and a slab below tolerance shall be evaluated by the Engineer of Record for removal and replacement.
+
+# Installation and Execution {toc}
+
+## Subgrade and Base Verification {toc}
+
+### The Contractor shall verify that the subgrade and aggregate base have been placed, compacted, proof-rolled, and accepted under [[syncs/aggregate-base-course]] and [[syncs/earthwork]] before placing any concrete.
+
+### The base shall be at the correct elevation and cross slope within tolerance, uniformly firm with no soft spots, and clean, dry, and unfrozen at placement.
+
+### The Contractor placing concrete accepts the base condition by paving over it, and shall report any deficiency in the base rather than placing concrete on it. {note}
+
+## Forms and Setting {toc}
+
+### Forms shall be set true to the line, grade, and cross slope shown, rigidly braced so they do not move under the weight and vibration of placement, and clean and oiled so the concrete releases cleanly.
+
+### Form grades and the resulting cross slopes on accessible walks and ramps shall be checked before placement, because correcting a slope after the concrete is placed means removal. {note}
+
+## Placement and Consolidation {toc}
+
+### Concrete shall be deposited as near as practicable to its final position, spread, and consolidated so it fills the forms and surrounds the reinforcement, dowels, and tie bars without segregating.
+
+### Concrete shall not be moved long distances by vibration, because vibrating concrete along the slab segregates it, leaving a coarse, weak zone where it was over-vibrated and a paste-rich zone where it ended up. {note}
+
+### Concrete shall not be retempered with added water to restore workability lost to time or heat, because the added water raises the water-cementitious ratio and weakens the surface.
+
+## Sawcutting Timing {toc}
+
+### The Contractor shall begin sawing the contraction joints as soon as the concrete will support the saw without raveling the edge, and shall complete all contraction joints before the concrete cools and shrinks enough to crack on its own.
+
+### In hot weather and on windy days the sawing window is short, and the Contractor shall have saws and crew ready to cut joints during the night or early morning if necessary to beat the random crack. {note}
+
+### Where early-entry dry-cut sawing is used, the first cuts shall be made within the equipment manufacturer's time window after finishing, sequenced so that the joints relieving the most restraint are cut first.
+
+## Protection of Fresh Concrete {toc}
+
+### Fresh concrete shall be protected from rain, which dilutes and pits the surface, and from foot and vehicle traffic until it has gained sufficient strength.
+
+### The pavement shall not be opened to construction or vehicular traffic until the concrete has reached the strength required for the imposed loads, commonly verified by field-cured cylinders or by a minimum age established for the mixture. {note}
+
+# Field Quality Control and Testing {toc}
+
+## Fresh Concrete Testing {toc}
+
+### The independent testing agency shall sample fresh concrete per ASTM C172 and test slump (ASTM C143), air content (ASTM C231), and concrete temperature at the frequency specified, and shall cast strength specimens (ASTM C31).
+
+```datasheet
+label: Fresh Concrete Test Frequency
+type: select
+options:
+ - "1 set per 50 cu yd, or 1 per day per mixture, whichever is more frequent"
+ - "1 set per 100 cu yd, or 1 per day per mixture, whichever is more frequent"
+ - "Per Engineer of Record / local Authority Having Jurisdiction"
+default: "1 set per 50 cu yd, or 1 per day per mixture, whichever is more frequent"
+```
+
+### Slump, air content, and temperature shall be tested at the point of placement at the start of each placement and whenever strength specimens are cast.
+
+### Concrete with air content outside the specified range, slump outside tolerance, or temperature outside the seasonal limits shall be rejected before placement.
+
+## Strength Testing {toc}
+
+### Compressive strength specimens shall be cast, cured, and tested per ASTM C31 and ASTM C39, with a set comprising specimens for 7-day and 28-day breaks plus a hold cylinder.
+
+```datasheet
+label: Strength Specimen Set
+type: radio
+options:
+ - "Cylinders for 7-day and 28-day breaks plus a hold/spare"
+ - "Beams for flexural strength (ASTM C78) where pavement is accepted on flexure"
+default: "Cylinders for 7-day and 28-day breaks plus a hold/spare"
+```
+
+### Strength acceptance shall be evaluated against the specified strength on the ACI 318 / ACI 301 statistical basis, and a failing strength result shall trigger investigation, coring (ASTM C42), or other evaluation as directed by the Engineer of Record.
+
+## Slope and Geometry Verification {toc}
+
+### The running and cross slopes of every accessible walk, ramp, and landing shall be measured and recorded before acceptance, and any segment exceeding the ADA limits shall be removed and replaced.
+
+```datasheet
+label: ADA Slope Verification Method
+type: radio
+options:
+ - "Digital inclinometer (smart level) readings recorded per segment"
+ - "Survey of finished surface elevations"
+ - "Both — inclinometer for slopes, survey for grades"
+default: "Digital inclinometer (smart level) readings recorded per segment"
+```
+
+### The detectable warning surfaces shall be verified for correct dome geometry, the 24 in. depth, full ramp width, dome-row orientation perpendicular to the grade break, and visual contrast.
+
+## Defective Work {toc}
+
+### Cracked, scaled, spalled, honeycombed, or out-of-tolerance concrete shall be removed and replaced to the nearest joint, not patched at the surface, because a surface patch on a cracked or scaled slab does not restore the slab and fails again. {note}
+
+### Random cracks that cross a panel (not at a joint) shall be evaluated by the Engineer of Record, and slabs with structural cracks shall be removed and replaced to the nearest joint lines.
+
+### Scaling, dusting, and surface defects attributable to inadequate air entrainment, overfinishing, finishing bleed water, or inadequate curing shall be corrected by removal and replacement of the affected slabs.
+
+# Delivery, Storage, and Handling {toc}
+
+## Concrete is a perishable, time-and-temperature-sensitive product, and the materials that go into it and the reinforcement embedded in it must reach the work undamaged and uncontaminated. {note}
+
+## Ready-mixed concrete shall be delivered and discharged within the time and drum-revolution limits of ASTM C94, and loads that exceed those limits or that have begun to set shall be rejected.
+
+## Reinforcing steel, welded wire reinforcement, dowels, and tie bars shall be stored off the ground and protected from contaminants that impair bond, and epoxy-coated dowels and bars shall be handled so the coating is not damaged, under [[syncs/concrete-reinforcement]].
+
+## Curing compound shall be stored in sealed containers protected from freezing, and shall be thoroughly agitated before use so the pigment and solids are uniformly dispersed.
+
+## Preformed joint filler, joint sealant, and detectable warning units shall be stored protected from weather, moisture, and damage until installed.
+
+# Warranty {toc}
+
+## The Contractor shall warrant the concrete paving, curbs, and sidewalks, including achievement of the specified strength, air content, thickness, finish, jointing, and ADA slope compliance, for the project warranty period beginning at substantial completion.
+
+```datasheet
+label: Concrete Paving Warranty Period
+type: select
+options:
+ - "1 year from substantial completion"
+ - "2 years from substantial completion"
+default: "1 year from substantial completion"
+```
+
+## Warranty obligations include correction of random cracking, surface scaling, spalling, joint failure, faulting at joints, settlement, and ADA slope non-compliance attributable to non-conforming materials or workmanship.
+
+## The warranty does not relieve the Contractor of liability for concealed non-conforming work, including deficient thickness, missing air entrainment, missing isolation joints, or undocumented failing tests, discovered after the warranty period expires.
+
+## Normal weathering, routine joint resealing, and damage from Owner deicer practices, snowplowing, or loads exceeding the design are Owner maintenance obligations and are not warranty items.