203 SECTION 418 DESCRIPTION
418.01.01 General. This work consists of placing a mixture of aggregate, mineral filler, bituminous material,
set-control additives, and water. MATERIALS
418.02.01 General. The bituminous material shall be Micro-Surfacing Emulsion conforming to Section 703 for
the type specified . Submit a 3.75 L (1 gal) sample of emulsified bituminous material for approval at least 14 days before use. Aggregate shall conform to Subsection 705.03.06 for the type specified. Produce, stockpile, sample, and test each specified aggregate size according to Section 106. Mineral filler , as required by the mix design, shall conform to Subsection 705.03.03. Use a set-control additive as required by the mix design. Water shall conform to Section 722 and shall be compatible with the mixture. Store materials in an area capable of preventing water saturation and contamination of stockpiled aggregates. Empty on-site emulsion storage tanks and clean of all residual asphalt prior to delivery of the first load of approved emulsion.
418.02.02 Mix Design. Before commencing micro-surfacing operation, submit a signed original of the mix
design for the micro-surfacing material. A separate signed original mix design for each aggregate and emulsion combination will be required. Have the design performed by a qualified laboratory approved by the International Slurry Seal Association (ISSA). Perform the design using materials that are to be used on the project. In the mix design, show the results of tests performed on the individual materials, comparing their values to the specification. Include the test result from the aggregates, emulsion, and micro-surfacing mixture. In the mix design, report the quantitative effects of moisture content on the unit weight of the aggregate (bulking effect). In the lab report, clearly show the proportions of aggregate, mineral filler (minimum and maximum), water (minimum and maximum), additives (usage) and asphalt based on dry aggregate weight. The mix design shall further show recommended changes in cement, water, and additive proportions for high temperature weather conditions by reporting proportions of materials required for 60 seconds of mix time. The micro-surfacing mixture shall conform to the following: TEST TEST METHOD REQUIREMENT Residual Asphalt, % of dry w eight of aggregate — 5.5 - 9.5 Mineral Filler, % of dry w eight of aggregate — 0.0 - 3.0 Wet Cohesion, 30 minute set ISSA TB139 12 kg/cm Minimum Wet Cohesion, 60 minute set ISSA TB139 20 kg/cm Minimum Excess Asphalt by LWT and Sand Adhesion ISSA TB109 50 g/ft2 Maximum Wet Stripping, % coating ISSA TB114 90 Minimum Wet Track Abrasion, 1 hour soak, loss ISSA TB100 50 g/ft2 Maximum Wet Track Abrasion, 6 day soak, loss ISSA TB100 75 g/ft2 Maximum Lateral Displacement ISSA TB147 5% Maximum Specific Gravity after 1000 cycles @ 125 lb ISSA TB147 2.10 Maximum Classification Compatibility ISSA TB144 (AAA, BAA) 11 grade points Minimum Mix Time @ 25 °C (77 °F) ISSA TB113 Controllable to 120 sec onds Minimum Mineral filler will be considered as part of the dry aggregate for the mixture. 418 MICRO -SURFACING 204 Furnish aggregates conforming to the mix design, within the following range of tolerances: Aggregate passing the 4.75 mm (No. 4) and larger sieves ................................ ................................ ................................ ................. ± 5% Aggregate passing the 2.36 mm to 150 µm (No. 8 to No. 100) sieves ................................ ................................ ................................ ± 4% Aggregate passing the 75 µm (No. 200) sieve ................................ ................................ ................................ ................................ ... ± 2% If it is established that a satisfactory micro -surfacing mixture mee ting the requirements specified herein cannot be produced from the materials furnished, the materials will be rejected. Submit new materials and a new mix design. Once the materials and mix design are approved, substitution of materials will require a new mix design. CONSTRUCTION
418.03.01 Equipment. Mix and apply the micro -surfacing mixture with a machine design ed and manufactured
to lay the mixture. Use a continuous run machine capable of loading materials while continuing to lay micro - surfacing, thereby minimizing construction joints. The continuous run machine shall be equipped to allow the operator to have full control of the forward and reverse speeds during applications of the mixture and be equipped with opposite side driver station to assist with alignment. The self loading device, opposite driver station, and forward and reverse speed controls shall be original manufacturer design. The machine shall be equipped with a continuous flow mixing unit, automatically sequenced and capable of delive ring accurately predetermined proportions of aggregate, water, and asphalt emulsion to a revolving multi -blade, double shafted, spiraled mixer tank. Provide a machine capable of mixing materials at pre -set proportions regardless of the speed of machine and without changing machine settings. Equip the mixing unit with a metering system to accurately meter all liquids by volume by the use of flow meters reading liters ( gallons ) per minute. The flow of the liquids shall be consistent and precise, and fed into the pugmill in the proportions outlined in the mix design. Equip the mixing machine with an approved fines feeder that provides an accurate metering device or method of introducing a predetermined proportion of mineral filler into the mixer as the aggregat e is fed in. Provide a mixing unit capable of thoroughly blending all ingredients together without violent action. The machine sh all also be capable of discharging the thoroughly mixed product on a continuous basis. Equip the machine with a hydraulically c ontrolled steel pugmill gate or similar positive discharge device. Control discharge from the pugmill by a chute or other suitable mechanical device. Equip the machine with a temperature indicating device installed in the emulsion tank at the emulsion pump suction level line. Equip the mixing machine with a water pressure system and fog type spray bar. The mixture shall be agitated and spread uniformly in the surfacing box by means of twin shafted paddles or spiral augers fixed in the spreader box. Provide a front seal to insure no loss of the mixture at the road contact point. The rear seal shall act as a final strike off and shall be adjustable. The spreader box and rear strike off shall be so designed and operated that a uniform consistency is achieved t o produce a free flow of material to the rear strike off. The spreader box shall have suitable means provided to side shift the box to compensate for variations in the pavement geometry. A secondary strike off shall be provided to improve surface texture. The secondary strike off shall have the same adjustments as the spreader box. Use a spreader box that is capable of producing a uniform surface up to 4.3 m ( 14 ft) in width . Ruts that are 12.5 mm (0.5 in .) or greater in depth shall be filled with a rut filling spreader which is 1.5 to 1.8 m (5 to 6 ft) wide. The rut box shall be designed to provide variable depth control, be double chambered, and shall include fixed hydraulic augers in the box. The augers s hall be set at an angle that will move the mixed material from the rear to the front of the filling chamber. The augers shall move larger aggregate material to the deepest portion of the rut and move the fine material toward the edges of the pass. Provide lighting for all equipment used. Give notification a minimum of 72 hours prior to the calibration of each mixing unit. Perform the calibration of each mixing unit within 24 hours prior to commencing micro -surfacing application. Provide facilities and fur nish all necessary equipment, personnel, and materials needed to calibrate and verify each mixing unit including the aggregate weight systems, emulsion metering devices, and mineral filler metering devices. Calibrate each mixing unit by approved methods at each project location and verify calibration as directed. Recalibrate each mixing unit after material changes and when there is repair or replacement of equipment components. Submit a calibration report for each mixing unit calibration and recalibration for approval prior to commencing operations. Include in the calibration report the mixing unit designation, date calibration was performed, emulsion source and type, mineral filler source and type, and aggregate source and gradation. Include in the calibra tion report the delivery rate of aggregate in kg (lb) per count of the head pulley, the delivery rate of emulsion in kg (lb) MICRO -SURFAC ING 418 205 per count of the head pulley, and the delivery rate of mineral filler in kg (lb) per count of the mineral filler counter. Submit gr aphs, measurements, and calculations used to determine the information in the report. Use the data from the aggregate, emulsion, and mineral filler calibrations to accurately set the mixing units to the optimum settings that will achieve the desired materi al proportions according to the approved mix design.
418.03.02 Preparation of Surface. Immediately before applying the micro -surfacing mixture, thoroughly
clean the surface. Remove loose material, vegetation, and other objectionable material by sweeping with self propelled pick up sweeper supplemented by hand brooms if necessary. Remove loose material in cracks. Water flushing will not be permitted . Perform removal of pavement markings as provided for in Section 202. Protect manholes, valve boxes, drop i nlets, curb s, gutters , and other facilities as directed by covering with paper, plastic, or other suitable material prior to the surfacing application. Remove material covering within 24 hours after the micro -surfacing has cured. Do not begin the applica tion of the micro -surfacing until the surface has been properly prepared and approved .
418.03.03 Mixture Preparation. Ensure that all oversized aggregate particles and other objectionable matter
is removed from the mineral aggregate. Screen the aggregate through a 12.5 mm ( 0.5 in .) screen prior to loading into the mixing unit. If approved, temporary use of screens attached to the distributor box may be permitted.
418.03.04 Water Fog. If road conditions require, and as directed, wet the surface by fogging immediately
prior to applying the mixture. Wet the surface such that the entire surface is damp with no apparent flowing water in front of the spreader box. Adjust the rate of application during the day to suit temperatures, surface texture, humidity, and dryness of the pavement surface.
418.03.05 Application. Prior to the start of work, place a test section of at least 1,250 m2 (1,500 yd2) in a
designated area. Place the test section using the same equipment, methods, and mixes as scheduled for use on the project. After placement of the test section, cease micro -surfacing application for a minimum of three days to allow for evaluation of the test section. W orking days will not be charged during the evaluation period. Test sections not conforming to the requirements of the plans and specifications will be rejected and shall be removed from the roadway and dispose d of according to Subsection 107.14. Make necessary adjustments to the mix design, equipment, and placement methods and c onstruct a dditional tes t sections , as specified above , until the surfacing meets requirements . Do not start permanent surfacing application until given approval. Test sections conforming to the plans and specifications w ill be considered as permanent micro -surfacing and will be measured for payment as specified in Subsection 4 18.04.01. An approved mixture shall be homogeneous, sufficiently stable during the entire mixing/spreading period so that the emulsion does not break prematurely, free of segregation of the fines from the c oarser aggregate, and shall have a liquid portion of the mix that does not float to the surface. Introduce the set control additive into the mixture by an approved method that will assure uniform distribution and proper control. Use water as indicated by the mix design. The mixture shall show no signs of uncoated aggregate, streaking, or premature breaking of emulsion when applied to the pavement surface. Specified ruts, cuts, and depressions in the pavement surface will require an ap plication of the micr o- surfacing mixture using the rut filling spreader box prior to full width application . The limits of these irregular areas will be shown in the contract. Place the preliminary applications of micro -surfacing mixture in courses not exceeding 20 mm (0.75 in .) in thickness to restore the existing roadway cross section or level the pavement surface. Allow traffic on each course for a minimum of two days between successive applications. Feed sufficient quantities of the micro -surfacing mixture into the spread er box so that uniform and complete coverage of the pavement is obtained. Operate the mixing machine at such a speed that the mixture in the spreader box does not exceed a total mixing time of 4 minutes and the volume remains constant. Place the micro - surfacing mixture at a rate of 14 kg of dry aggregate per square meter ( 25 pounds of dry aggregate per square yard) unless otherwise specified . Application rates adjusted for smooth or rough pavement surface textures may be applied outside of the specified ran ge, as approved. Do not leave any streaks caused by oversized aggregate particles or buildup of micro -surfacing mix on squeegees in the finished surface. If excessive streaking develops, cease operations until the situation has been corrected. Excessive s treaking is defined as more than four drag marks greater than 12.5 mm ( 0.5 in .) wide and 100 mm ( 4 in.) long, or 25 mm ( 1.0 in .) wide and 75 mm ( 3 in.) long, in any 23 m2 (27 yd2) area. Transverse 418 MICRO -SURFACING 206 ripples or longitudinal streaks of 5 mm ( 0.2 in.) in depth or more will not be allowed, when measured by placing a 3.6 m ( 12 ft) straightedge over the surface. Place the mixture such that edge lines are straight along all curbs, gutters, and shoulders. Runoff will not be allowed. Lines at intersections shall be straight. Compact rut filling applications and other areas as directed with a minimum 3.6 metric ton (4 ton) and a maximum 9 metric ton (10 ton) pneumatic tire d roller when material is set sufficiently. Roll a minimum of 2 coverages and until a u niform surface is obtained. Submit a signed written report each working day indicating the amount of aggregate and emulsion delivered, aggregate and emulsion used on the project, the amount of area in square meters ( square yards ) completed, the percentage of emulsion used to aggregate used, the application rate in kilograms of aggregate applied per square meter (pounds of aggregate applied per square yard ) of area covered, and the type of additive used.
418.03.06 Joints. Place longitudinal joints on the lane lines . Do not allow excessive build -up, uncovered
areas , or unsightly appearance on longitudinal or transverse joints. The longitudinal joint between adjacent lanes shall be butt joints with overlaps not to exceed 75 mm ( 3 in.). Butt joints shall ha ve no visible lap, pinholes, or uncovered areas. Immediately smooth thick spots caused by overlapping with hand squeegees before the emulsion breaks. Smooth overlaps which occur at transverse joints before the emulsion breaks so that a uniform surface, whi ch contains no discontinuities, is ob tained. When a 3.6 m (12 ft) straightedge is laid perpendicular across any joint, the finished surface shall not deviate at any point more than 6 mm (0.25 in.) from the bottom thereof.
418.03.07 Hand Work. Use hand squeegees with burlap drags to spread the mixture in areas not accessible
to the spreader box. Exercise care in leaving no unsightly appearance from the work . Remove all runoff on the curb and gutters, and other areas as directed, using approved methods.
418.03.08 Curing. Allow areas receiving micro -surfacing to cure at least one hour or until the treated
pavement will not be damaged by traffic. Protect the area from traffic for the full curing period. Repair areas that are damaged within 24 hours of appli cation of micro -surfacing prior to moving to new work locations.
418.03.09 Sweeping. Five days after micro -surfacing application, sweep surface d areas to remove excess
raveled material that becomes dislodged. Dispose of dislodged material according to Sub section 107.14.
418.03.10 Weather Limitations. Do not apply micro -surfacing mixture unless both the pavement and air
temperatures are 13 °C ( 55 °F) and rising. Do not apply micro -surfacing mixture when there is forecast of the atmospheric temperature drop ping below 0 °C ( 32 °F) within 24 hours of placement. Do not apply the micro - surfacing mixture when precipitation is imminent. Do not apply micro -surfacing mixture when the surface temperature exceeds 46 °C (115 °F) or when the atmospheric temperature exce eds 35 °C (95 °F). METHOD OF MEASUREMENT
418.04.01 Measurement. Micro -surfacing emulsion and micro -surfacing aggregate will be measured by the
metric ton (ton). BASIS OF PAYMENT
418.05.01 Payment. The accepted quantities, measured as provided above, will be paid for at the contract
price per unit of measurement for the pay items listed below that are shown in the proposal. Payment will be full compensation for the work prescribed in this Section. Payment will be made under: Pay Item Pay Unit Micro -Surfacing Emulsion (type) ................................ ................................ ................................ ................................ ...... Metric Ton ( Ton) Micro -Surfacing Aggregate ( type) ................................ ................................ ................................ ................................ .... Metric Ton ( Ton) 207 SECTION 501 PORTLAND CEMENT CONCRETE DESCRIPTION
501.01.01 General. This work consists of proportioning, placing, and curing Portland cement, aggregates,
water , and when specified, admixtures. MATERIALS
501.02.01 General. Materials shall conform to the following Sections:
Portland Cement ................................ ................................ ................................ ................................ ................................ ...... Section 701 Concrete Curing Materials and Admixtures ................................ ................................ ................................ .............................. Section 702 Aggregates for Portland Cement Products ................................ ................................ ................................ ............................... Section 706 Water ................................ ................................ ................................ ................................ ................................ ....................... Section 722
501.02.02 Aggregates. Produce and stockpile adequate quantities of aggregate sufficiently in advance of
construction operations as to permit sampling, testing , and mix designs before use. Give not less than 32 days notification in adva nce of use of the proposed sources of materials and make arrangements for the Engineer to obtain samples as required for testing purposes. When requested, exceptions to the above requirement may be granted in writing when the aggregate source has been previously tested within the past one year and accepted by the Department. When producing Portland cement concrete, use the same aggregates used in the approved mix design. Store aggregates in stockpiles sufficiently removed from each other to prevent th e materials at the edges of piles from becoming intermixed, and to allow sampling by heavy equipment. Use lightweight aggregates specified in Subsection 706.03.02 only where lightweight concrete is specified or is approved. For Class E and EA concrete, u se a three aggregate system consisting of a blend of two Coarse Aggregates from Subsection 706.03.01 and Fine Aggregate conforming to Subsection 706.03.03. If approved, the 25 mm (1 in.) combined grading limits may be used in lieu of the 19 mm (3/4 in.) combined grading limits. Use American Concrete Institute, Manual of Concrete Practice, Guide 302.1R -04, Section 5.4.3 Combined Aggregate Grading to optimize the combined aggregate grad ing within the grading limits in Subsection 706.02.01. Submit the results with the mix design. Provide necessary means to obtain an aggregate sample from the batch plant conveyor belt. Construct the sampling device so representative samples may be taken a s required. Deliver the samples by mechanical means to a point on the ground or other satisfactory safe and accessible location. If two consecutive sieve analysis results are out of specification, reprocess the failing stockpile or stockpiles. If three co nsecutive sieve analysis results are out of specification, the stockpile or stockpiles will be rejected. Once rejected material has been replaced, provide test results indicating the new material is within specification. The gradation requirements represe nt the extreme limits in determining the suitability of material. Maintain the gradation from any one source, for any one contract, at a uniformity such that variations in the fineness modulus will not exceed ± 0.2 from the “Base Fineness Modulus.” The “Ba se Fineness Modulus” shall be the average of the most recent 10 fineness modulus values (or the average of all preceding values if less than 10 have been completed) from any one source, for any one contract. Fine aggregate from any one source, for any one contract, having a variation in fineness modulus of more than 0.2 as prescribed above will be rejected or may be accepted subject to approved changes.