for Highway Construction Page 266 of 715 SECTION 411 – URBAN CONCRETE PAVEMENT
411.01 Description.
Construct portland cement concrete pavement s as specified in 409.01.
411.02 Materials.
Provide materials and test as specified in 409.02.
411.03 Construction Requirements.
A.Proportioning. Meet the requirements as specified in 409.03.A with the following exceptions:
1.Use number 3 coarse aggregate or 3C combined aggregate gradation as specified in 703.02.
2.The Contractor may increase maximum slump to 3 inches if finishing machines that provide only surface vibration are used and 4 inches if hand methods are used.
3.The Engineer may require Type III cement where earlier pavement strengths are necessary.
B.Equipment.
1.Mixers and Hauling Equipment . Meet the requirements specified in 409.03.B.1.
2.Paving Equipment. Meet the requirements specified in 409.03.B.2.
a.Placer/Spreader. Meet the requirements specified in 409.03.B.2. a.
b.Slipform Paving. Use equipment as specified in 409.03.B.2.b.
c.Machi ne Paving with Forms . Provide forms so the constructed pavement meets the specified thickness, cross- section, grade, and alignment. Adequately support forms to prevent deflection or movement. Do not allow the top of the forms to deviate more than 1/8 inch in 10 feet and do not allow the alignment of the forms to deviate more than 3/16 inch in 10 feet . Allow the concrete to set sufficiently to withstand form removal without chipping or spalling when forms are removed the day after placement . Spray the edges of the concrete with curing compound if forms are removed before the expiration of the curing period. Clean, oil, and examine used forms for defects before they are used agai n. Use machines, or combination of machines, capable of consolidating the concrete across the full width of the placement into a uniform and homogeneous mass, without rock pockets, and without separation of mortar and aggregates. Machines may be subject t o Engineer approval. The Engineer may request a test section placed to show the equipment can satisfactorily strike off and compact the concrete to the required density, grade, and sections. The Contractor may use internal, pan, beam, or roller type vibrating units. Do not operate the vibration equipment when the machine is not in motion. Run machines to consolidate, finish to the established grade and cross -section, and establish a smooth even surface so only a very moderate amount of hand finishing is necessary. for Highway Construction Page 267 of 715 Do not overwork the concrete and bring an excess of fines to the surface. Remove water or laitance from the surface with a grout rod or scraping straightedge at least 10 foot wide with a long handle and operated from the pavement edge. Perform the finishing operations as needed.
d.Bridge Deck Machine. Use equipment as specified in 409.03.B.2.d. Use the following sequence of operati ons for placing concrete with any of the methods described in this section:
1.Strike -off.
2.Consolidate.
3.Float.
4.Remove laitance.
5.Straightedge.
6.Final surface finish. Do not add water to the surface of the concrete during this sequence of operations.
3.Concrete Sawing Equipment. Meet the requirements specified in 409.03.B.3.
C.Handling, Measuring, and Batching Materials . Meet the requirements specifi ed in 409.03.C.
D.Mixing and Delivering . Meet the requirements specified in 409.03.D.
E.Conditioning of Subgrade or Base Course . Meet the requirements specified in 409.03. E.
F.Temperature L imitations . Meet the requirements specified in 409.03.F.
G.Hand Placing Concrete . Meet the requirements specified in 409.03.G.3. Limit hand methods to irregular areas, irregular sections, and pavement placed in confined work areas Moisten the forms and surface of the base immediately ahead of the placement of concrete pavement . Place concrete in a continuous operation between construction joints . Deposit concrete so rehandling is minimized. Spread concrete evenly. Do not use vibrators for extensive shifting of the mass of concrete. Use surface vibrators, internal vibrators, or other equivalent method to produce consolidation without segregation . Ensure adequate consolidation next to forms and uniformly across the full pavement width. Strike off concrete to the intended surface profile after consolidation. Smooth concrete by floating after it has been struck off and consolidated. Do not move ahead in successive advances more than ½ the length of the float. Continue floating until irregularities are removed. Float the concrete within 30 feet of the consolidation effort. Rem ove free water on the pavement with the float or other suitable tool. for Highway Construction Page 268 of 715 Thoroughly consolidate concrete against and along forms or adjoining pavement so gravel pockets along the edges of the fi nished pavement are prevented. Repair gravel pockets found after removing the forms. Place reinforcing steel around hardware (e.g., manholes, valve covers, street monuments ) as specified or as directed. Allow local traffic access by placing concrete in intermittent areas or leaving temporary gaps in the pavement . The Engineer may request a test section to show the proposed operation is capable of satisfactorily consolidating and striking off the concrete to the required grade and section. Scrape the surface of the concrete with a grout rod after floating. Use a grout rod at least 10 foot long with a long handle for operating at the edge of the pavement . Use the grout rod to correct irregularities in the pavement surface and remove water and laitance.
H.Joints . Transverse and longitudinal joints for urban pavement may be contraction joints or construction joints. Where possible, place longitudinal joints on lane lines except through transitions and in intersections. For intersections and other irregular areas, place joints as specified in the joint location plan or as directed.
1.Stress Relief Joints . Form or saw transverse and longitudinal contraction joints.
a.Construct formed contraction joints by embedding a pre- formed joint material. Cut filler to the exact sections of the joint. Extend the length of the pre- molded joint filler to within 3/16 inch of both panel edges. (1). Transverse Contraction Joints . Place transverse contraction joints (dummy joints) after consolidation and finishing of concrete have been completed and before i nitial set. Cut a groove into the surface at the location of the joint, using a tool provided with st ops (tee iron) to prevent cutting the groove deeper than the planned depth of the joint filler . Insert joint filler into the groove un til the top is flush with the pavement surface, with a deviation of not more than 1/ 8 inch below the surface. Ensure joint filler is at right angles to the surface and always in a straight line. (2). Longitudinal Contraction Joints . Construct longitudinal contraction joints in true alignment with respect to their proper location on centerline or parallel to the plan joint location. If multiple lanes are constructed simultaneously, use a sawed joint instead of the preformed joint material. Restore the surface finish of the pavement against the filler strip w ith hand floats after the joint filler has been embedded in the concrete. While performing this operation, maintain filler strip in a vertical or normal position, true to alignment. After finishing, ensure the entire area of the joint is true to grade and smoothness without irregularities.
b.Meet the requirements specified in 409.03.H.
2.Sealant Reservoir Construction. Meet the requirements specified in 409.03.H.2.
3.Tie Bars . Meet the requir ements specified in 409.03.H.3.
4.Load transfer Devices. Meet the requirements specified in 409.03.H.4.
5.Construction Joints . Place construction joints as follows: for Highway Construction Page 269 of 715 a. Transverse Construction Joints . Make transverse construc tion joints at the end of each day's paving, or when placing of concrete is discontinued for more than 45 minutes. Place the construction joint at the same location as would be used for a contraction joint, if possible. If the joint occurs at other locations, construct a joint using tie bars at least 6 feet away from the nearest contraction joint.
b.Longitudinal Construction Joint s. Locate longitudinal construction joints as specified in the joint location plan or as directed.
6.Random Cracks. Meet the requirements specified in 409.03.H.6.
I.Tolerance in Pavement Thickness. Provi de as specified 409.03.I.
J.Final Finish. Float slab after screeding if necessary, to produce a uniform surface without porous spots, irregularities, depressions, small pockets, or rough spots. Use a steel tine to finish the surface. Provide tines that are approximately 4 inches long and spaced at approximately 1/2 to 3/4 inch intervals. Use nominal tine width of 1/8 inch. Ensure the depth of tined grooves is 5/32 inch ± 1/32 inch. Check groove depth in accordance with Idaho IT 147. Make adjustments to the tining operation when more than three readings in a set of ten are outside depth range. Perform the tining in such a way as to minimize surface tearing or aggregate removal. Tine with stroke transverse to the roadway centerline and f ull width of the roadway, except for troweled smooth strips 1 foot wide along curb faces. Do not overlap adjacent strokes.
K.Surface Test. Meet the requirements specified in 409.03.K.1 to test the pavement and ap plicable sections for grinding.
L.Curing. Meet the requirements specified in 409.03.L.
M.Cold Weather Concreting Plan. Provide as specified in 409.03.M.
N.Sealing Joints . Provide as speci fied in 409.03.N.
O.Multiple Lane Construction. Provide as specified in 409.03.O.
P.Protection of Pavement . Provide as specified in 403.03.P.
Q.Opening Pavement to Traffic. Provide as specified in 409.03.Q, except t o protect curbs cast separately from the pavement for 72 hours by keeping traffic off the adjacent pavement or by placing barricades along the curb . for Highway Construction Page 270 of 71 5 411.04 Method of Measurement. The Engineer will measure acceptabl y complete d work for urban concrete pavement by the square yard. Measurement will be based on the width of the top surfac e of the pavement as shown on the typical cross - section of the plans with additional widening where specif ied or directed. The length will be measured horizontally along the centerline of the roadway. Pavement areas will be computed according to Table
109.01 1.
The Engineer will not make a final measurement of the completed pavement except for authorized changes during construction, or where many errors are found in the contract quantity . The Engineer will compute a revision or correction and add to or deduct from the contract quantity.
411.05 Basis of Payment .
The Department will pay for accepted work at the contract unit prices as follows: Pay Item Pay Unit Urban Concrete Pavement ..................................................................... SY Drilling holes for the dowels is incide ntal and the cost included in the contract unit prices of other concrete pavement items. Verifying dowel bar location is incidental and the cost included in the contract unit prices of other concrete pavement items. The Department will not pay for field- cured cylinders. The Department will not pay for grinding and related expenses, including disposal of ground material, traffic control, flagging, profiling, and temporary striping. Thickness Price Adjustment . The Department will make the following price adjustment to the applicable contract unit prices for each evaluation section quantity exceeding the thickness shown and as specified in Table 411.0 5-1. If thickness measurements show deficie nt thickness, the Contractor has the option of removing and replacing the pavement at no additional cost to the Department or leaving the pavement in place and receiving deductions in payment as specified in Table 411.05- 1. Table 411.05-1 – Thickness Price Adjustment Excess or Deficiency in Thickness, inches Price Adjustment , Percent of Contract Unit Price Over +0.50" 100 +0.35" through +0.50" 102 +0.25" through +0.34" 103 +0.11” through +0.24” 105 +0.10" through -0.10" 100 -0.11" through - 0.24" 85 -0.25" through - 0.34" 70 -0.35" through - 0.50" 50 Over - 0.50" 0 for Highway Construction Page 271 of 715 The Engineer will evaluate areas of pavement found deficient in thickness by more than 0.5 inch and determine if the deficient area is sufficient to seriously impair the anticipated service life of the pavement. Remove the affected areas of pavement within the limits specified and replace it with concrete of the specified quality and thickness at no additional cost to the Department. Remove the sections of pavement the full length between transverse joints . If, as determined by the Engineer, a deficiency in excess of 0.5 inch will not seriously impair the anticipated service life of the pavement , the Contractor may elect to leave the pavement in place, but will not receive payment for the deficient area of pavement. When the pavement contains no longitudinal joints , the area of such pavement for which no payment will be made by the Department is the product of t he full width of the strip placed as a unit, multiplied by the distance between probes, on both sides of the deficient measurement that shows measurements within the thickness limits. Where the pavement contains longitudinal joints, the width used by the D epartment is the width between longitudinal joints and the edge of the pavement. The Engineer may order the Contractor to core drill the finished pavement to determine thickness of the pavement in areas where smoothness corrections are mad e. The Engineer will determine the pavement thickness by coring after smoothness corrections have been completed. 412-414 for Highway Construction Page 272 of 715 SECTIONS 412 -414 - RESERVED for Highway Construction Page 273 of 71 5 SECTION 415 – MICROSURFACING
415.01 Description.
Microsurface as specified. Provide a microsurfacing mix placed with a properly proportioned blend of fine graded aggregate, liquid admixture, polymer -modifie d emulsified asphalt , and water. Use the mixture to fill ruts and as an evenly spread surface treatment. Ensure the cured slurry is homogeneous, fills cracks, and adheres firmly to the surface wi th a skid resistant texture.
415.02 Materials.
Provide materials as specified in: Asphalt ......................................................................................................................................... 702 Aggregate ................................................................................................................................ 703.03
415.03 Construction Requirements.
Determine when microsurfacing is to be mixed and spread after the emulsified asphalt arrives on the project site. Shotting. While some shotting (small beads of asphalt in suspension in the emulsion) is normal for the emulsion, an excessive amount of shotting is an indication that the emulsion is ready to break and should not be used.
A.Mix Design . The mix design is the Contractor’s responsibility. At least 2 weeks before microsurfacing, submit a complete mix design that meets the specification. Use the same component materials, aggregate and gradation in the mix design as will be provided on the project site. Submit a new mix design to the Engineer if aggregate source, aggregate blend, gradation, or asphalt emulsion source is changed. Provide the component materials within the following limits: Residual asphalt ............................................................... 5.5% to 10.8% by dry weight of aggregate Mineral filler ........................................................................ 0.0% to 3.0% by dry weight of aggregate Polymer -based modifier .............................. Minimum of 3% solids based on bitumen weight content Provide a mix design that meets the following International Slurry Seal Association (ISSA) test requirements: ISSA Test No. Description Specification ISSA TB- 100 (a) Wet Track Abrasion Loss 1-hour soak 6-day soak 50 g/ft2 maximum 75 g/ft2 maximum ISSA TB- 113 Mix Time @ 77 °F Controllable to 120 seconds minimum ISSA TB- 147 Lateral Displacement (Loaded Wheel Test, Method A) 5% maximum
Source: Idaho Standard Specifications for Highway Construction, 2023 Edition. Pages 302–308 of 768.