Ohio Department of Transportation Central Office 1980 West Broad Street Columbus, OH John R. Kasich, Governor Jerry Wray, Director

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1 Ohio Department of Transportation Central Office 1980 West Broad Street Columbus, OH John R. Kasich, Governor Jerry Wray, Director 7/14/2015 Project Addendum No. 5 PID No PIK SR Major Reconstruction Letting: July 16, 2015 Notice to all Bidders and Suppliers to please be advised of the attached Proposal Addendum. The Department utilizes Bid Express ( as the official medium for electronic bid submittal. All bidders must prepare bids and submit them online via Bid Express. Addenda amendments must be acknowledged in the miscellaneous section of the Expedite (EBS) file and all amendments loaded in order for your bid to be considered for award of this project. Bid express will not accept bids that do not have amendments incorporated. Failure to incorporate changed quantities or items in your Expedite (EBS) submissions will result in the rejection of your bid. ODOT is an Equal Opportunity Employer and Provider of Services

2 Proposal Addendum For PIK ; PID Project Completion Date Change: No Bid Item Changes, Additions or Deletions: Yes Funding Splits Required: No Revised Bid Items: Ref. No. Item No. Total Quantity Unit Description Section E ,336 CY EMBANKMENT, AS PER PLAN A E ,151 CY EXCAVATION OF SUBGRADE E HOUR PROOF ROLLING E ,509 CY DUMPED ROCK FILL, TYPE B, AS PER PLAN 0002 Please be advised of the following: 1. SPECIAL PROVISIONS ITEM 511 CONCRETE, MISC:ROLLER COMPACTED CONCRETE has been updated and attached. 2. Please replace the note ITEM 201 EMBANKMENT, AS PER PLAN A on sheet 10 with the following: ITEM EMBANKMENT, AS PER PLAN A THE CONTRACTOR SHALL MEET THE REQUIREMENTS OF ITEM 203 IN THE CONSTRUCTION AND MATERIALS SPECIFICATIONS (CMS) IN ADDITION TO WHAT IS NOTED BELOW: ALL EMBANKMENT FILL SHALL BE DEFINED AS COHESIVE SOIL (i.e., CL, CL-ML, CL-CH, CH, SC) THAT HAS AN ORGANIC CONTENT OF LESS THAN 2 PERCENT AND DOES NOT INCLUDE MATERIALS CONSIDERED TO BE DETRIMENTAL TO THE FUNCTIONALITY OF THE DAM AS DETERMINED BY THE ENGINEER. FILL MATERIAL SHALL INCLUDE AT LEAST 50 PERCENT BY WEIGHT PASSING THE NO. 200 SIEVE WITH A PLASTICITY INDEX OF AT LEAST 8 AND NO GREATER THAN 40. PARTICLES LARGER THAN 3-INCHES MUST BE BROKEN DOWN OR REMOVED. LABORATORY COMPACTION TESTING (ASTM D698 OR AASHTO T-99) TO BE PERFORMED ON EACH SOIL TYPE THAT IS TO BE INCORPROATED AS EMBANKMENT FILL, WITH TEST RESULTS SUBMITTED TO AND APPROVED BY THE ENGINEER AND ODNR PRIOR TO PLACEMENT/COMPACTION OF EMBANKMENT FILL.

3 ALL AREAS TO RECEIVE FILL ARE TO BE STRIPPED OF TOPSOIL AND ORGANIC MATERIALS. THESE AREAS ARE TO BE OBSERVED AND INSPECTED BY THE ENGINEER PRIOR TO FILL PLACEMENT. ANY AREAS DETERMINED TO BE UNSUITABLE FOR FILL PLACEMENT ARE TO BE OVEREXCAVATED AND REPLACED WITH EMBANKMENT FILL. FILL SHALL NOT BE PLACED ON A FROZEN SUBGRADE, NOR SHALL SNOW, ICE OR FROZEN MATERIALS BE INCORPORATED INTO THE FILL. HORIZONTALLY BENCH SLOPED SURFACES THAT ARE TO RECEIVE FILL SUCH THAT FILL CAN BE PLACED IN HORIZONTAL LIFTS. PRIOR TO EMBANKMENT FILL PLACEMENT, THE AREAS TO RECEIVE FILL ARE TO BE PROOFROLLED TO IDENTIFY SOFT OR WEAK AREAS THAT NEED TO BE STABILIZED. PROOFROLLING IS TO BE OBSERVED BY THE ENGINEER. SOFT OR WEAK AREAS SHALL BE OVEREXCAVATED AND REPLACED AS DIRECTED BY THE ENGINEER. THE FOLLOWING CONTINGENCY ITEMS HAVE BEEN INCLUDED TO BE USED AS DIRECTED BY THE ENGINEER IN THE EVENT THAT SOFT OR WEAK SUBGRADE IS ENCOUNTERED AND OVER-EXCAVATION IS REQUIRED: ITEM 203 EMBANKMENT, AS PER PLAN A 2200 CY ITEM 204 EXCAVATION OF SUBGRADE 2200 CY ITEM 204 PROOF ROLLING 1 HOUR EMBANKMENT FILL IS TO BE COMPACTED TO A MINIMUM OF 98 PERCENT OF MAXIMUM DRY DENSITY AS DETERMINED BY THE "STANDARD" COMPACTION TEST (ASTM D698 OR AASHTO T99) WITH A MOISTURE CONTENT CONTROLLED BETWEEN MINUS ONE (-1) AND PLUS THREE (+3) PERCENT OF THE OPTIMUM MOISTURE CONTENT. TOPSOIL IS TO BE COMPACTED ONLY BY THE WEIGHT OF THE GRADING EQUIPMENT. ALL FILL IS TO BE PLACED IN LIFTS NO GREATER THAN 8-INCHES (BEFORE COMPACTION). MOISTURE-DENSITY TESTING OF IN-PLACE EMBANKMENT FILL SHALL BE PERFORMED AT A FREQUENCY OF NO LESS THAN ONE (1) TEST PER 500 CUBIC YARDS OF FILL PLACEMENT/COMPACTION OR NO LESS THAN ONE (1) TEST PER SOIL LIFT PLACED/COMPACTED PER DAY. BACKFILL SHALL BE PLACED ADJACENT TO STRUCTURES IN A MANNER WHICH WILL PREVENT DAMAGE TO THE STRUCTURES AND WILL ALLOW THE STRUCTURES TO ASSUME THE LOADS FROM THE FILL GRADUALLY AND UNIFORMLY. THE WEIGHT OF THE FILL ADJACENT TO A STRUCTURE SHALL BE INCREASED AT APPROXIMATELY THE SAME RATE ON ALL SIDES OF THE STRUCTURE. THIS PROCEDURE IS ESSENTIAL WHEN BACKFILLING AROUND THE INTAKE STRUCTURE. SCRAPERS, SELF-PROPELLED OR PULL-BEHIND COMPACTORS, AND OTHER HEAVY EQUIPMENT SHALL NOT BE OPERATED WITHIN 10 FEET OF STRUCTURES.

4 PIPELINES THAT ARE TO REMAIN ARE TO BE PROTECTED FROM DAMAGE. ANY PIPING DAMAGED DURING CONSTRUCTION SHALL BE REPLACED AT THE CONTRACTOR'S EXPENSE. IF THE TOP SURFACE OF THE PRECEDING LAYER OF COMPACTED FILL OR A FOUNDATION OR ABUTMENT SURFACE UPON WHICH FILL IS TO BE PLACED BECOMES TOO DRY TO PERMIT A SUITABLE BOND, THAT SOIL LAYER SHALL, EITHER, BE REMOVED OR BE SCARIFIED AND MOISTENED BY SPRINKLING WATER AND DISCING TO MOISTURE-CONDITION THE SOIL TO WITHIN THE PREVIOUSLY- DEFINED MOISTURE CONTENT LIMITS PRIOR TO PLACEMENT OF THE NEXT LAYER OF FILL. WHERE EMBANKMENT FILL IS TO BE PLACED ADJACENT TO AN EXISTING EMBANKMENT, THE TOPSOIL IS TO BE STRIPPED AND THE EMBANKMENT FILL BENCHED INTO THE EXISTING EMBANKMENT BY EXCAVATING 10 TO 20-INCHES HORIZONTALLY INTO THE EXISTING EMBANKMENT FOR EACH LIFT. ANY INSTABILITY CAUSED BY EARTHWORK OPERATIONS MUST BE IMMEDIATELY STABILIZED AND THE ENGINEER NOTIFIED. THE CONTRACTOR SHALL FURNISH ALL LABOR, EQUIPMENT AND MATERIALS NECESSARY TO COMPLETE THE WORK. PAYMENT FOR ALL WORK WILL BE INCLUDED IN THE PRICE BID PER ITEM 203 EMBANKMENT, AS PER PLAN A. Add the following Note: No Plan sheets: No Answers to Prebid Questions: Yes Q1: The bid item 203 Embankment, As Per Plan A general note on sheet 10 states that; Prior to embankment fill placement, the areas to receive fill are to be proof-rolled. and soft or weak areas shall be over-excavated and replaced as directed by the Engineer. Furthermore, the note states that payment for all work is to be included in the bid item Embankment, As Per Plan A. It is unreasonable to place this risk on the contractor since no one knows how much undercutting will be required. Please add bid items with contingency quantities for proof rolling, excavation of unsuitable material, and backfill of over-excavation to pay for the work described in the general note. A1: Please replace the note ITEM 201 EMBANKMENT, AS PER PLAN A on sheet 10 with the revised note.

5 STATE OF OHIO DEPARTMENT OF TRANSPORTATION SPECIAL PROVISIONS ITEM 511 CONCRETE, MISC: ROLLER COMPACTED CONCRETE Description Submittals Materials Equipment RCC Handling, Measuring, and Batching Materials Construction Joints Work Stoppage RCC Finishing Curing and Protection Maintenance RCC Elevation and Lift Thickness RCC Test Section Quality Control and Quality Assurance Method of Payment Basis of Payment Description. This work shall consist of furnishing all roller compacted concrete (RCC) aggregates, cement, fly ash, water, and admixtures for RCC; and furnishing all mixing plants, equipment, facilities, and labor to proportion, mix, transport, place, compact, and cure the RCC. Contractor Objectives 1. The CONTRACTOR shall be responsible to plan, execute and complete the RCC construction with little or no interruption, to ensure a quality RCC armoring for the dam. 2. RCC shall be placed and compacted to the lines and grades shown on the drawings and as specified herein. 3. Provide RCC armoring for the dam that has met the fresh and hardened properties specified herein. The CONTRACTOR shall provide quality measures during the process of batching, mixing, transporting, placing, compacting and curing to achieve these requirements for the RCC armoring. 4. Definitions and Terms- In addition to ODOT specification and : a. Roller Compacted Concrete (RCC) - RCC is a lean, no-slump concrete that is mixed or blended in a moist condition, spread in horizontal lifts, and compacted in-place by vibratory rollers, or when lack of work area does not permit the use of vibratory rollers, by plate compaction equipment. It is a mixture of aggregate, cement, pozzolan, water, and is sometimes supplemented with admixtures. b. Average maximum density (AMD) - Average in-place wet density of compacted RCC determined from a control section. c. Bonding Grout - Grout applied to improve bonding of consecutive lifts of RCC. The grout is applied to the underlying lift of RCC just before the next consecutive lift is placed. ROLLER COMPACTED CONCRETE 1

6 d. RCC Total Moisture Content - The total moisture content of all of the constituents in the fresh RCC, as determined by a nuclear gauge or laboratory oven. e. Saturated surface dry (SSD) - The condition of the aggregate and sand when it is fully absorbed with water and surface dry. f. Quality Control (QC) - The CONTRACTOR s quality program that shall be used to evaluate and check the requirements within this specification. g. Quality Assurance (QA) - The OWNER s quality program that will be used to verify the requirements herein during construction Submittals. CONTRACTOR shall submit required information within 30 days following Notice to Proceed and at least 90 days before start of any RCC production unless otherwise specified. 1. Aggregate source- Within 60 days of notice to proceed, provide a report from an Independent Materials Testing Laboratory that includes supplier name, location of mine and geologic formation and location of aggregate processing plant. The report shall provide testing results for each aggregate type identified herein section and in comparison to testing requirements identified herein section Cement, Fly ash and admixture source- Provide Mill Certification test reports for each cement, fly ash and admixture source to be used on the project. Reports shall include information indicating compliance as required herein section Provide this information within 30 days following notice to proceed. 3. Water source approval- Water test reports indicating the water source is reliable and sustainable during the production of the RCC and meets the quality requirements herein. Use of Lake White water or water from Aqua Ohio water wells located at the site is prohibited. Provide this information within 30 days following notice to proceed. 4. Bonding grout- Submit a mix design for grout that would include cement and admixture types that will achieve the requirements in C to be used for bonding required RCC lift joints and areas where RCC comes into contact with concrete, as required in g and Submit a description of the methods and equipment for delivering grout to the placement at all locations. 5. Forming system- Submit detailed calculations and drawings of forming system, manufacturer's catalog, data and descriptive literature for formwork, anchors and all associated hardware. Also submit schedule and procedures for form installation and removal, material and procedures for patching form anchor holes. 6. Narrative description of all materials to be used in the RCC and schematic drawings describing plan for haul routes, traffic control measures, number type and weights (fully loaded) of haul vehicles, overpass clearance height restrictions, bridge weight restrictions. Narrative shall also include production quantities required to maintain RCC placement rates for each material used in the RCC, methods for protecting aggregates from segregation, maintaining aggregate moisture condition required for batching, and measures for preventing materials from freezing. Narrative description of measures to avoid cross contamination of cement and fly ash upon loading into silos. Provide narrative at least 90 days before starting placement of RCC. 7. Aggregate testing reports for each aggregate product used in the RCC on a weekly basis. Summarize testing results into one report for both quality and gradation testing for each aggregate ROLLER COMPACTED CONCRETE 2

7 product used in the RCC. Highlight any non-conformance test results and indicate any retesting that was done for non-conforming test results. 8. Quality Control Plan 30 days before the start of the RCC test section. The plan shall include how the CONTRACTOR will maintain quality for the entire operation during construction. Organization chart showing key individuals including Production Supervisor, Placement Supervisor, Plant Operators, and Quality Control Manager. CONTRACTOR and any Subcontractor involved with RCC production and placement shall demonstrate experienced in production and placement of RCC by having at least two jobs of similar quantity and scope within the past 3 years. Foreman/Superintendent and RCC plant operator shall be experienced in production and placement of RCC with at least two jobs of similar quantity and scope within the past 3 years. Contractor shall have these experienced operators running the plant at all times. Resumes for each key individual showing applicable experience on similar projects and total years of experience. Identify key personnel with their roles and responsibilities and the procedures that shall be followed to meet the requirements for the 1) Individual material to be used in the RCC; cement, fly ash, water, admixtures and aggregates and the 2) RCC pertaining to batching, transporting, placing, spreading, compacting, temperature, curing and weather restrictions. The plan shall also include RCC quality control testing and calibration procedures required for each batching plant. Revisions may be required by the ENGINEER upon the completion of the RCC test section. Submit a revised quality control plan 30 days prior to the start of RCC placement. 9. Delivery tickets for each delivery of cement or fly ash that show source, date manufactured, type or class, CONTRACTOR S name, project name, and certification that materials meet specification requirements herein. Delivery ticket shall accompany monthly pay estimates. 10. Representative material samples within 120 days of trial placement. Ship samples in moisture proof and air tight drums for RCC trial mixture testing including RCC aggregate, cement, fly ash, admixtures and water in quantities as follows: a. Aggregate: 3000 pounds b. Cement: 300 pounds c. Fly ash: 300 pounds d. Water: 200 pounds e. Admixtures: 5 gallon bucket 11. Plan for RCC Batch Plant facility: a. Equipment descriptions, specifications, and number of pieces for all equipment used for batching and mixing RCC. b. Narrative descriptions and schematic drawings describing RCC batch plant and RCC materials storage locations. c. Narrative description of batching process of RCC material constituents into mixer and mixing time. d. RCC plants peak capacity and anticipated production rates throughout placement and total storage needed for RCC constituents to maintain RCC production rates. e. Methods and equipment for handling and transporting RCC constituent materials from storage silos and stockpiles to batch plant. f. Facilities for sampling RCC component materials and batched RCC materials at the RCC mixing plant, and methods of controlling RCC temperature within specified limits. g. Narrative description of calibration process for plant during the course of construction. ROLLER COMPACTED CONCRETE 3

8 12. Plan for RCC Transporting and Placement: a. Equipment description, specifications, and number of pieces of all equipment used for transporting RCC. Narrative descriptions and schematic drawings describing: i. RCC delivery system ii. Location and alignment of temporary access roads iii. Locations of fixed equipment iv. Methods and equipment for delivering batched RCC to the placement area v. Methods for handling RCC at intermediate and exit points along conveyor system b. Narrative descriptions and schematic drawings describing the plan for RCC placement, including: i. Spreading, compaction, curing, and protection including direction and configuration of placement ii. Placement widths iii. Methods for constructing formed, stepped, RCC outside edge iv. Methods and equipment for joint cleanup and waste disposal v. Methods for placing RCC in inclement weather (hot, cold, wet, etc.) including heating/cooling of materials and admixtures vi. Methods and material for curing and to prevent damage to completed work 13. RCC placement schedule describing the RCC placement areas and rates, number of RCC lifts placed each day and lift-by-lift construction sequence. 14. Plan for RCC Test Section Submit plan that includes the following: a. Narrative descriptions and schematic drawings describing layout and design of the RCC test section including plan and cross sections, alternative methods and equipment to construct stepped RCC outside edge and construction joints; methods and equipment to saw cut and core RCC testing section for observation and testing, with narrative describing how specification requirements shall be demonstrated in the test section. b. Schedule for constructing RCC test section, obtaining cored samples, and performing laboratory tests at desired age days. 15. Report describing proposed final RCC construction methods and equipment to be submitted within 30 calendar days after completion of the RCC test section construction, but not less than 30 calendar days prior to the start of the RCC placement in the dam armoring. 16. Prior to placement of RCC, excavate to the limits shown on the drawings or required by the ENGINEER in accordance with Item 203. Prior to placing RCC, prepare the foundation in accordance with Item 203 Embankment as per Plan A and Item Materials. Furnish materials conforming to: 1. RCC Mix Constituents a. Portland cement: Type II - ASTM C150 b. Fly ash: Class F - ASTM C618 c. Chemical Admixture: Type D - ASTM D494 d. Additional Requirements: Submit a minimum of 2 sources of fly ash from coal-fired power plants. Cement and fly ash that have not been used within 6 months after the date of ROLLER COMPACTED CONCRETE 4

9 manufacture, certification, and testing shall be retested at the CONTRACTOR S expense. Cement and fly ash not meeting specification requirements after retesting shall be rejected. e. Aggregates used in the production of RCC shall consist of a manufactured sand and crushed rock and conform to the following requirements: i. Fine aggregate - Shall be a manufactured sand that meets the following requirements: a) Grading Sieve Size Percent Passing by Weight No No No No No No No b) Sand Equivalent of in accordance with ASTM D c) Non-plastic in accordance with ASTM D4318 (wet method). d) Clay lumps and friable particles are not to exceed 1 percent in accordance with ASTM C142. e) Light weight particles shall not exceed 2 percent in accordance with ASTM C123. ii. Coarse aggregate- Shall be a manufactured crushed aggregate that meets the following requirements: a) Grading in accordance with ASTM C136 Sieve Size Percent Passing by Weight 1 inch 100 3/4 inch /2 inch /8 inch No No b) LA Abrasion: Less than 40 percent loss in accordance with ASTM C131. c) Fractured Particles: A minimum of 85 percent fractured faces, in accordance with ASTM D5821. d) Clay Lumps & Friable Particles: Less than 1 percent in accordance with ASTM C142. e) Sodium Sulfate Soundness: Less than 12 percent loss in 5 cycles in accordance with ASTM C88. iii. Medium aggregate- Shall be a manufactured crushed aggregate that meets the following requirements: ROLLER COMPACTED CONCRETE 5

10 a) Grading Sieve Size Percent Passing by Weight 3/8 inch 100 No No No No b) LA Abrasion shall not have a loss greater than 40 percent in accordance with ASTM C131. c) Fractured Particles shall have a minimum of 100 percent fractured faces in accordance with ASTM D5821. d) Clay Lumps & Friable Particles Clay lumps and friable particles shall not exceed 1 percent in accordance with ASTM C142. e) Sodium Sulfate Soundness shall not have a loss that exceeds 12 percent at 5 cycles in accordance with ASTM C88. iv. The combined aggregate (coarse, medium and fine) shall conform to the following gradation requirement for the RCC: Sieve Size Percent Passing by Weight 1 inch 100 3/4 inch /2 inch /8 inch No No No No No No No v. An all-in-one aggregate type (combined aggregate) may be provided, in lieu of the three aggregate types (coarse, medium and fine) above, provided the following criteria is maintained: a) The all-in-one aggregate type is manufactured thru an aggregate processing plant and is not blended using other equipment types. b) The all-in-one aggregate type shall maintain the gradation and quality requirements in this section thru the entire process of transporting to the site, stockpiling at the site and loading material to the RCC batch plant. c) The moisture condition of the combine aggregate will be maintained at near SSD conditions. d) The coarse, medium and fine portions of the all-in-one aggregate shall meet the quality requirements in this section, paragraphs i, ii, iii and the gradation requirements in paragraph iv above. e) The contractor shall submit 30 days in advance of the test section a plan that will include how the all-in-one aggregate type will meet the requirements in this section, paragraphs i, ii, iii, iv and v. ROLLER COMPACTED CONCRETE 6

11 2. Mixing water used in the production of RCC shall be potable water tested to demonstrate adherence to the requirements in ASTM C1602. Water used for RCC shall be free from sewage, oil, acid, salts, strong alkalis, organic matter, clay, loam, and other materials that adversely impact the quality of the concrete. 3. RCC Mix- The mixture proportions for RCC to be placed in the dam armoring shall be approved by the ENGINEER following evaluation of the RCC trial mixture testing and construction and evaluation of the RCC test section. The initial RCC mixture proportioning is as follows: a. Portland Cement pounds per cubic yard of RCC. b. Fly Ash pounds per cubic yard of RCC. c. Water pounds per cubic yard of RCC. d. Aggregate pounds per cubic yard of RCC. e. Type D admixture- anticipate 14oz cwt. f. Adjustment of the RCC mixture proportions may be required by the ENGINEER based on results of mixture design testing performed by the OWNER's material testing laboratory and results from the test section. Mixture proportions shall be adjusted for workability, consistency, density, strength, durability, and economy. The quantity of water shall be adjusted to achieve a workability that allows efficient compaction throughout the entire lift thickness. The quantity of water shall be adjusted to account for variations in consistency due to fluctuations in aggregate moisture content, aggregate grading, wind conditions, ambient temperature, and RCC mixture temperature. In addition, the quantity of water shall be adjusted to achieve a target Vebe consistency of 20 seconds, plus or minus 5 seconds. g. RCC placed in the dam armoring shall have a minimum compressive strength of 3,000 pounds per square inch (psi) by 90 days. 4. Bonding Grout Mixture a. Make use of the bonding grout for RCC as required in section and and use bonding grout where RCC comes into contact with any concrete. The bonding grout will be used to make a bond: a. Between a consecutive fresh lift of RCC and the underlying lift of RCC that has reached a joint maturity in section g and; b. Provide a bond between the fresh RCC and any concrete, including underlying concrete cutoff walls. b. Mixture proportions shall be adjusted to bring grout to a broom-able consistency. In no case shall the water to total cementitious materials ratio exceed 0.50 by weight. c. Bonding grout placed in the dam armoring shall have minimum strength of 2,500 psi at 28 days. d. Make use of admixtures, if necessary to provide lengthened setting during hotter seasons of the year and allow for the advancement of RCC. ROLLER COMPACTED CONCRETE 7

12 Equipment Minimum Requirements. 1. Batch Plant a. The batch plant (s) shall have a demonstrated history of supplying a uniform RCC mixture at a sustained rate of 200 cubic yards an hour and be compatible with the CONTRACTOR S transportation system and placement equipment. b. The plant shall be a weigh batching plant or a continuous mixing (pug mill) plant. Drum mixing plants are not allowed. Two mixing plants are recommended, but not required, to ensure minimal down time associated with plant maintenance and breakdowns. c. The weighing operation of each material shall meet the tolerances listed in section d. Provide separate silos for bulk storage of Portland cement and fly ash. Each silo shall be labeled and have couplings and fittings for transferring cement and fly ash into the silos. Each silo shall be a different size to avoid the possibility of placing or storing material in the wrong silo. e. The plant shall have separate loading bins for each RCC aggregate to be used in the RCC mix. Aggregate loading bins shall be self-cleaning during drawdown. The bins shall have steep side slopes, large gate openings, and be capable of handling the aggregate in a damp condition without choking. f. The plant shall be equipped with a suitable water measuring device such as a water meter, located between the water supply and mixer. The water meter shall have a dial or digital indicator and be automated and capable of using aggregate moisture content values to determine final water content needed in batch. Filling and discharge valves from the water batcher shall be interlocked so that the discharge valve cannot be opened before the filling valve is closed. A suitable strainer shall be provided ahead of the water measuring device. The plant shall be capable adjusting the water in real time to compensate for varying moisture condition of the aggregate and placement conditions. g. A separate batcher or dispenser shall be provided for each approved admixture. Volumetric dispensers shall be used only for liquid admixture and each plant shall be equipped with the necessary calibrated devices that permit checking of the accuracy of the dispensed volume. Piping shall be leak free and properly valved to prevent backflow or siphoning. The dispensing system shall include a device capable of detecting the presence or absence of admixture and its flow. Each dispenser shall be capable of varying the quantity of admixture and adding admixture in a manner to ensure uniform flow distribution throughout the mixture. h. Maintain and operate the plant and all of its batching components, silos and conveying equipment to prevent spillage of batched material and overlap of batches. Any spilled or wasted material shall not be considered for payment. Prevent dust generation during measuring and discharging of materials, loading of cement and fly ash silos and aggregate bins and silos. Spilled materials shall be managed in accordance with the Storm Water Protection Plan and removed to prevent adverse water quality impacts to existing waterways. 2. Transportation Equipment- All transportation equipment shall be capable of transporting RCC material from the mixing plant to the point of placement. a. The transportation equipment shall have a capacity that equals or exceeds that of the mixing plant. The maximum free-fall drop height allowed for the RCC shall be 15 feet. The total length of time from the end of mixing until compaction shall not exceed 60 minutes. Methods and equipment for transporting RCC are subject to the approval of the ENGINEER. b. RCC material may be hauled and deposited using trucks or conveyor system or a combination of both vehicles, except that trucks shall not be allowed to traverse on and off the RCC placement footprint. Trucks shall be shielded to protect the RCC. Trucks may only be used ROLLER COMPACTED CONCRETE 8

13 to transport RCC if the trucks are permanently stationed on the RCC placement footprint and if they are loaded with a surge or gob hopper. All equipment used for transporting RCC on the RCC placement footprint shall be free of deleterious materials, including, but not limited to soil, rock, or mud; uncompacted, loose deteriorated, or improperly cured RCC material; and concrete materials from removed RCC lifts. Clean the undercarriage and tires or tracks of the vehicles of all such substances prior to entering onto the dam armoring placement area. Maintain all equipment in good operating condition to prevent spilling or dripping oil, grease, or other contamination onto the RCC. Operate all equipment to not make tight turns, sudden stops, or other procedures that might damage or cause rutting deeper than 1-inch on previously compacted RCC. c. All conveyor belts used for transporting RCC shall be shielded to continuously protect and prevent drying of the RCC by the wind and sun, and by over-wetting from rain. Bucketed conveyors shall be used for vertical lifts of RCC mixture. Conveyor belts with cleats shall be used to lift RCC mixture up steep inclines. The equipment shall be designed for continuous operation with no-slump, large-aggregate concrete. The locations, capacities, speed, reach, and pivot points for all belts shall be identified. Interim storage at gob hoppers or chutes shall be provided between conveyance stations to avoid segregation of the RCC and provide for continuous transportation of the RCC. Gob hoppers and chutes shall be self-cleaning as RCC is discharged. Conveyor belts at transition points shall be designed to self-clean RCC from belt using belts scrapers that deposit RCC into chutes or gob hoppers. Provide telephone or radio communication between interim storage hoppers, the plant control room, and the placement site. 3. Spreading Equipment- Spreading equipment shall be capable of placing a smooth level surface of the RCC. RCC shall always be placed on top of the lifts leading edge and shall not be deposited in front of, or within 2 feet of, the leading edge. Provide suitable track mounted bulldozers that have controls to hydraulically adjust blade tilt and angle for spreading the RCC in layers, resulting in smooth and uniform surfaces. Spreading equipment shall be equipped with laser controls to produce compacted lifts within the specified tolerance requirements. Track-mounted vehicles shall be equipped with low ground pressure road plates in lieu of grousers. Spreading equipment shall be maintained in good operating condition and not allowed to spill or drip oil, grease, or other apparent contamination onto the RCC. Provide front-end loader(s) or backhoe(s), with operator(s), to assist with materials as needed. Operated equipment shall not be allowed to travel on compacted finished lifts without the use of rubber mats, so that damage does not occur to the finished lift. 4. Compacting Equipment. Provide equipment capable of physical and practical operation in all compaction areas. Provide the largest equipment practicable and suitable for areas to be compacted. Self-propelled vibratory rollers, in good operating condition and meeting these requirements, shall be maintained on the placement area at all times. Compacting equipment shall be maintained in good operating condition and not allowed to spill or drip oil, grease, or other apparent contamination onto the RCC. The number of rollers required on the placement area shall be determined by the CONTRACTOR S approved placement methods and schedule. a. Self-propelled vibratory rollers shall be single-drum or dual-drum drive. The vibratory rollers shall meet the following requirements and shall not be operated within 2 feet of the formed step edge: i. Minimum dynamic force per unit width of drum: 400 pounds per linear inch at operating frequency used during compaction. ii. Amplitude: to inches iii. Frequency: Not less than 2,000 cycles per minute. iv. Rolling speed: Not greater than 2 miles per hour (less than 30 feet in 10 seconds). ROLLER COMPACTED CONCRETE 9

14 b. Small self- propelled rollers shall be used close to the edge of the formed step and shall be sized to produce acceptable compaction results and to meet alignment tolerances, subject to approval by the ENGINEER. Compact the step and top of lift to the AMD developed in the control section. c. CONTRACTOR shall provide a standby roller on site during RCC placement to replace a defective or broken down vibratory roller. Rollers shall not remain stationary with vibratory mechanism operating. d. Use small vibratory rollers to compact irregular or tight access areas. Small rollers shall be capable of operating within a few inches of a vertical face. Use hand operated tampers in areas that cannot be reached with the drum of a vibratory roller. 5. Water Equipment- Provide water distribution equipment on site and available at all times for dust suppression measures, keeping the RCC in a damp condition, joint preparation and general cleaning of the RCC lift. Equipment shall consist of pumps, water tanks, sprinklers, or other approved equipment. Adequate equipment, subject to approval, shall be available at all times to provide water 24 hours per day, seven days per week for curing and protection of permanently exposed slopes for duration of 7 days after RCC has been placed. For surfaces receiving an overlay of RCC, keep RCC in a moistened condition and free from any surface water 24 hours per day until RCC is covered by next lift of RCC. Use curing blankets as necessary to keep the RCC moist for permanently exposed surfaces and for compacted RCC ready to receive another lift of RCC. Do not place RCC on surfaces that have standing water or puddles of water. Remove standing water or puddles of water using high pressure air wand and brooming. Water trucks or sprinklers to be used for the above purposes shall be equipped with fog-type sprayers. Ensure water distribution and curing system does not cause excessive run off, puddling or deterioration on the RCC lift. Ensure any run off is captured and mitigated properly, to prevent environmental impacts. Curing compounds are not allowed. 6. Forms for RCC Steps - Forms and supporting systems shall be designed and constructed to withstand the anticipated loading pressures resulting from placing and compacting equipment operating adjacent to the form. 7. Other Equipment. All other equipment necessary for use on the RCC placement area, but not previously discussed within these specifications or determined to be necessary during the course of the work, shall be proposed by the CONTRACTOR subject to approval of the ENGINEER before and during actual use. This shall include but not be limited to equipment used to install the transverse contraction joints, horizontal joint preparation or curing of the RCC. Any use of such equipment shall not result in any damage to the RCC and the equipment shall be maintained in good operating condition at all times while on the RCC placement area RCC Batching, Transporting and Placing for Production. The RCC shall be batched, transported and placed in a continuous operation, with little or no interruption for each shift of work. The total elapsed time for mixing, transporting, placing and compacting the RCC shall not exceed 60 minutes. The entire system of batching, mixing, transporting, placing and compacting shall provide an RCC that meets the fresh and hardened properties of the RCC specified herein and with little or no segregation as determined by the ENGINEER. 1. Batching shall conform to the following requirements: a. Batching Operations- The aggregate, Portland cement, fly ash, and water shall be accurately measured and conveyed into the mixer in the proportionate amounts necessary to meet the specified requirements. All ingredients shall be mixed to ensure a thorough, ROLLER COMPACTED CONCRETE 10

15 uniform, and intimate mixture of the aggregates, cement, fly ash, admixture (s) and water and until the resulting mixture is homogeneous and uniform in appearance. b. The CONTRACTOR shall calibrate the plant to NRMCA standards and furnish calibration report to the ENGINEER, one week before the trial placement. Perform plant calibration every 50,000 cubic yards, after initial calibration. c. Batching/Measuring- The measuring operation of each material shall be batched within specified tolerances below: Material Fly ash Cement Water Aggregate Admixture Accuracy Limit Plus-or-minus 1 percent Plus-or-minus 1 percent Plus-or-minus 1 percent Plus-or-minus 2 percent Plus-or-minus 3 percent d. RCC Materials- Before and during production, provide sufficient quantity of each material type to be used in RCC mix to maintain RCC production with no interruption. i. Aggregate moisture content shall be kept close to SSD and the moisture distribution within the coarse medium and fine aggregate shall be uniform. The CONTRACTOR shall test the moisture content as necessary for each aggregate type, coarse medium and fine to account for any moisture condition above SSD and make adjustment to batched water to account for any free water above SSD If the coarse, medium or fine aggregate moisture content become too nonuniform to deliver RCC of the right consistency, as determined by the ENGINEER, the CONTRACTOR shall be required to dry aggregate(s) back to a uniform state or remove and replace with aggregate at the uniform moisture content, as determined by the ENGINEER. ii. Water- Provide water that meets the requirements in ASTM C1602. iii. Cement- Provide cement meeting the requirements in ASTM C150, type II. Ensure cement is delivered and stored in a dry state at all times. Remove cement from the project if it becomes damp or has not been used for a period exceeding 6 months. iv. Fly ash- Provide fly ash meeting the requirements in ASTM C618, Class F. Remove fly ash from the project if it becomes damp or has not been used for a period longer than 6 months. v. Admixture- Keep admixtures stored in a dry condition and use within the time frame recommended by the manufacturer. 2. Mixing. Mixing equipment shall conform to the following requirements: a. Lay out the plant so that the mixing action of each mixer can be observed from a safe location which can be reached from the mixing plant control station. Provide safe areas where the ENGINEER can observe RCC in the receiving hopper(s), buckets, or conveyers as it is dumped from the mixer. b. Control each mixer by a timing device which indicates, and ensures, completion of required mixing period. c. Equip mixing plant with an interlocking mechanism which prevents materials from entering mixing chambers that are not empty. ROLLER COMPACTED CONCRETE 11

16 d. Set the mixing time for 60 seconds and run the RCC operation to perform mixer uniformity test. The CONTRACTOR shall be responsible for assisting the Owners onsite laboratory performing the testing associated with mixer uniformity. e. Mixer uniformity testing shall be performed by the Owner s Independent Materials Testing Laboratory in accordance with ASTM C 94, during the first two lifts of RCC placed at the time of test section construction and for every 20,000 cubic yards of RCC produced. The results of the mixer uniformity must be within the parameters tabulated below, before continuing with the remaining lifts of RCC in test section and before the placement of the RCC with in the dam armoring limits. CONTRACTOR shall perform more frequent proportioning and uniformity tests, as required by the ENGINEER, when proportioning and mixing do not produce materials meeting the quality, cementitious material content, or segregation requirement of these specifications. Any additional mix uniformity required by the ENGINEER due to poor RCC quality or retesting of mixer uniformity shall be at the CONTRACTOR s own expense. Test Allowable Maximum Difference (Percent) Water content of full mix (percent by weight) 15 Coarse aggregate content of concrete (plus No. 4, percent by weight) 15 Unit weight of full mix 2 Unit weight of air-free mortar 2 Air content of full mix 100 Compressive strength at seven days 25 Vebe time 20 f. If the CONTRACTOR wants to reduce the mixing time below the stated time, the CONTRACTOR shall perform mixer uniformity and provide assistance to the Owners Independent Materials Testing Laboratory performing testing as discussed above. The CONTRACTOR shall also be required to pay for all costs associated with the OWNER s laboratory testing. 3. Transporting RCC - The CONTRACTOR may use conveyors, trucks or a combination of both to transport the RCC to the footprint of the dam, with the exception that trucks shall not be allowed to traverse on and off the footprint of the RCC placement. Gob or surge hoppers shall be used to load trucks that are permanently stationed on the dam to place the RCC. Minimize, as much as possible, the total elapsed time between the RCC mixing and compacting, to ensure the RCC remains cohesive during the placing and spreading and workable enough to provide the maximum density while being compacted. The RCC shall be mixed and transported to the RCC placement footprint, within 15 minutes from the end of mixing. a. Trucks shall have shielding for RCC, if transporting is done from the plant or as necessary to keep the RCC in a cohesive and workable condition. b. Trucks shall avoid making sharp turns on the RCC during transportation and placing, to avoid rutting. If the RCC is not workable enough to make satisfactory repairs of rutting using rollers and dozer, as determined by the ENGINEER, replace RCC to the bottom of the rut, apply grout and fill and compact rut with fresh RCC. c. Trucks shall be required to stay a minimum of 4 feet away from the finished edge of the RCC, to avoid damaging the formed edge. d. Trucks shall not cause deep rutting of the RCC. Deep ruts shall be considered anything deeper than 3 inches. Rollers shall be used to repair any rutting, and repair shall be ROLLER COMPACTED CONCRETE 12

17 performed as each truck exits the point of placement. If RCC is not workable to make satisfactory repairs using rollers and dozer, as determined by the ENGINEER, replace RCC to the bottom of the rut, apply grout and fill and compact rut with fresh RCC. e. Conveying RCC- RCC shall be conveyed in a manner that maintains the intact fresh properties of the RCC produced by the batching plant. Conveyor belts shall be operated at speeds which meet production requirements. 4. Placing and Spreading RCC Mixture- The surface on which RCC is placed shall be moistened and kept moist until overlying RCC is placed. Place and spread the RCC within 45 minutes of the end of mixing. a. The RCC shall be constructed in as nearly a continuous operation as practical and in a manner to produce a concrete mass with sufficient continuity and continuance so that it hardens and performs as a monolithic mass with no discontinuous joints or potential planes of separation or weakness other than those preformed joints included in the design. Unless otherwise approved or required by the ENGINEER, placement shall be at essentially the same level across its entire area. Exposed edges of RCC shall be covered and compacted through an appropriate sequence of placement, spreading, and compacting so that all the edges are compacted within the time limits specified. b. RCC shall be placed in near horizontal layers. Place mixture on the prepared surface with spreading equipment that prevents segregation and that produces layers having widths and thicknesses appropriate for compaction to the required dimensions. Place each successive layer as soon as practicable after the preceding layer is completed. c. Do not place RCC on ruts deeper than 3 inches, caused by placing, spreading or transporting equipment, for areas that will receive the next lift of RCC. Immediately repair ruts to the satisfaction of the ENGINEER using dozers and rollers while the RCC is still in a cohesive and workable condition. If ruts cannot be repaired to the satisfaction of the ENGINEER using dozers and rollers, remove RCC to the bottom of the rut in the area affected, spread grout in the affected area and place fresh RCC on top of grout and compact. d. If the density and Vebe requirements of are being met, the maximum temperature of the RCC delivered to the point of placement shall not exceed 85ºF. If, during placement of a batch, the temperature of the RCC at point of placement rises to exceed 85 degrees, the remainder of the batch may be placed as long as workability is met, however a new batch of RCC shall not be made until RCC temperature controls are implemented. If the density and Vebe requirements of are not being met due to RCC placement temperature, cool the RCC until the density and Vebe requirements of are met, as follows: i. The contractor may make use of chilled water or ice at the batch plant during the hotter seasons to reduce the temperature of RCC. Do not add ice without compensating for it in the total allowable water. Suspend RCC placement if measures to cool the RCC do not result in the density and Vebe requirements of being met. Do not attempt to add water on the lift, or during the placement, spreading or compacting of RCC to reduce the temperature or improve the consistency of the RCC at any time. e. Provide a rain gauge and thermometer, subject to approval by the ENGINEER, at the site for measurement of precipitation and temperature. Do not place RCC when the ambient temperature drops below 40 F. During temporary periods when the temperature is below this level, the CONTRACTOR may be permitted to place RCC if the surface of the previously compacted layer and the temperature of the mixture stay above 40 F. If the ambient temperature drops below 40 F, cover the RCC surface with heavy tarp, blankets, straw or other acceptable temporary protection until the temperature rises above 40 F. ROLLER COMPACTED CONCRETE 13

18 RCC may not be placed during heavy rain (more than 0.3 inch per hour or 0.03 inch in 6 minutes as defined by the Weather Bureau Glossary of Meteorology). If unusual adverse weather such as heavy rain, severe cold, heavy snow, etc. occurs, or is forecast to occur during placement, an interruption in placing operations may be approved or required. All placed RCC materials shall be fully compacted prior to stopping work. The CONTRACTOR shall allow for any construction schedule risk and added expense that could occur as a result of adverse weather, and shall receive no additional compensation because of weather delays, including the CONTRACTOR S costs for treatment of any cold joints which may result from the occurrence of adverse weather. f. RCC shall be deposited and spread by methods that do not cause segregation. No RCC shall be placed on a previously-placed layer which has not been completely compacted and approved by the ENGINEER. Equipment shall not be operated on lift surfaces when free water develops on the compacted RCC surface as a result of rain or overwatering. Excess water shall be removed by squeegees or other suitable equipment prior to continuation of work. g. Compacted surfaces of RCC that are to receive an overlying or adjacent layer of RCC shall be kept moist continuously until the overlying or adjacent layer of RCC has been placed. Do not allow moisture conditioning of RCC lift to puddle or use RCC lift surface to divert water from placement area. h. Do not place RCC on an underlying lift of RCC that has a joint maturity longer than 48 hours, without treating the joint as required herein section i. Damaged RCC shall be removed down to undamaged RCC. RCC that is allowed to freeze shall be removed down to unfrozen RCC. The final surface exposed during removal shall be treated as required herein section This treatment includes removal of any laitance, loose debris, contamination, defective RCC or bonding grout. Clean final exposed surface of RCC by air jetting or water jetting. Only jet surface as necessary to expose, but not undercut, aggregate. Vacuum the cleaned surface and maintain in a saturated, surface dry condition until bonding grout is applied. Apply bonding grout to the surface of lift just before the new lift of RCC is applied. 5. Compaction- Begin compaction immediately behind RCC placement and complete compaction within 15 minutes after spreading RCC and within 60 minutes after mixing RCC. Use largest compaction equipment practical for area being compacted. Use number of roller passes and optimum roller speed, vibration frequency and amplitude to achieve the maximum density at the fastest production rate as determined from results of the Control Section. Operate roller in static mode for first pass and vibratory mode only when the roller is moving. Compact all RCC material uniformly throughout the entire depth of the lift. All compacted surfaces shall be free from undulation, tracks, ruts or roller marks greater than 1-inch deep. Prevent rutting of the RCC; by avoiding abrupt stops with roller in vibratory mode. Overlap adjacent roller passes at least one foot. Do not operate roller within one foot of the edge of a freshly placed lane until adjacent lane is placed. Operate rollers to prevent damage to RCC and do not allow rollers to make tight turns and abrupt stops on the RCC. If plate compactors are used, the maximum compacted layer thickness shall be 6 inches, or as otherwise required by the ENGINEER. The RCC surface shall be dense and sealed with aggregate held firmly in place by mortar fraction of the RCC mix. If rock pockets occur in the surface of RCC lift, remove and replace the affected areas with grout and fresh RCC. Compact area with roller to achieve a smooth tight surface and required density. a. Compact adjacent to formed steps using approved appropriately sized placing equipment and compacting equipment to achieve required compaction and to achieved required alignment tolerances. Provide sufficient compaction energy to consolidate RCC to its AMD as determined in the control section. ROLLER COMPACTED CONCRETE 14