SECTION PORTLAND CEMENT CONCRETE PAVING

Transcription

1 SECTION PORTLAND CEMENT CONCRETE PAVING PART 1 GENERAL 1.01 DESCRIPTION A. This Section includes specifications for constructing concrete curb, gutter and sidewalk, concrete base, concrete pavement, and curb ramps at the locations and to the dimensions shown on the plans, in accordance with the Project Manual. B. Preparation of subgrade to proper elevation including excavating, backfilling, removal of existing curb, existing sidewalk, existing road base, existing pavement, existing curb ramp, and compaction as required shall be done as Incidental Work to the above mentioned new concrete work. C. Tree roots under sidewalk and pavement areas shall be removed with a sharp edge instrument to a depth of eight (8) inches below finished grade as Incidental Work. Feeder roots greater than two (2) inches in diameter shall be checked by the Bureau of Urban Forestry. Call the Customer Service number 311 prior to removal by the Contractor REFERENCE A. Standard Specifications of the City and County of San Francisco, Department of Public Works, Bureau of Engineering (SSDPWSF), revised November, B. Standard Plans of the City and County of San Francisco, Department of Public Works, Bureau of Engineering dated April SPECIAL INSTRUCTIONS A. Notifications 1. Underground Service Alert a. Before commencing any excavation, obtain Underground Service Alert inquiry I.D. number by calling the following phone number: Underground Service Alert: b. Allow four (4) calendar days after I.D. number is obtained and before excavation work is started so that utility owners can be notified by Contractor. c. I.D. numbers will not be given more than 10 calendar days prior to starting excavation work Portland Cement Concrete Paving

2 B. Curb Ramps 1. Curb ramps shall be constructed in accordance with the details shown in the Standard Plans. 2. Investigate subsidewalk basement in sidewalk area prior to saw cutting and excavation for curb ramps. If there is a subsidewalk basement and there is sufficient cover to construct the curb ramp, proceed with saw cutting and excavation with care. If there is not sufficient cover to construct the curb ramp, notify the Engineer and stop the construction of the curb ramp. 3. The Contractor shall notify the County Surveyor at (415) of any monuments in danger of disturbance destruction or removal. All city monuments must be protected per State Land Surveyors Act and these Specifications. The Contractor shall not disturb, destroy or remove any survey monuments without the approval from the County Surveyor. The Contractor shall salvage any monuments removed during construction and shall deliver these monuments to the survey department at 1680 Mission Street. 4. The Contractor shall complete the construction of curb ramp, curb and sidewalk repairs work within 72 hours from commencement of excavation work, so as not to obstruct pedestrian traffic or travel thereon more than is reasonably necessary. C. Broken Water Meter Boxes 1. Replace any broken San Francisco Water Department (SFWD) meter boxes before placing new sidewalk. Call SFWD at (415) to pick up the meter boxes free of charge. D. Temporary Asphalt Concrete 1. The temporary asphalt concrete on the restored concrete base shall be removed by the Contractor before placing the asphalt concrete wearing surface. 2. Full compensation for installing and removing the temporary asphalt concrete surface on the concrete base areas before placing asphalt concrete wearing surface shall be considered as Incidental Work to the appropriate bid items. E. California Code and Regulations 1. The Contractor shall comply with all OSHA Code requirements during this contract. Article 37, Section 2946 Provisions for Preventing Accidents Due to Proximity to Overhead Lines and Article 37, Section 2947 Warning Signs Required. F. Muni Railway 1. If Muni overhead wires are encountered, the overhead wires will be kept energized at all times. The overhead trolley wires carry a minimum of 600 Volts DC and have an 18 +/- feet clearance from the existing roadway. The Contractor shall adapt his methods and equipment to this condition, and shall take Portland Cement Concrete Paving

3 G. Local Access precautions against accidents and damage to the overhead wires and feeder cables when performing paving work with lines and feeders energized. 1. The Contractor shall provide local access to garages by the end of each work shift by placing steel plate(s) over excavated area(s). It shall be the Contractor s responsibility to notify residents of the construction schedule prior to any work that may disrupt access to garages or other entrances and provide access during construction where as needed or requested by the Engineer. H. Spray Paint 1. Prior to the start of construction, the Contractor shall furnish the Engineer with ten (10) spray paint cans as Incidental Work at no additional cost to the City. I. Limit Construction Activities: 1. Excavation site may not exceed 1,200 linear feet at any time. J. Survey Control 1. Where roadway pavement reconstruction occurs, the Contractor shall be responsible for providing primary control, with control line and grades, from existing off-site monument markers and lines. The Contractor shall maintain and preserve all lines, grades, and benchmarks and provide for all other survey control work. The Contractor shall establish construction control line with hubs every 25 feet prior to construction work. 2. The Contractor shall replace or reestablish hubs missing or displaced during construction at no cost to the City. 3. The Contractor shall retain the services of s State of California registered land surveyor with minimum of one (1) year experience in engineering surveying and control procedure for public works construction, who shall establish horizontal and vertical controls as needed by the Contractor. 4. The survey control work shall be considered Incidental Work and no separate payment will be made. K. Cobblestones 1. In the event cobblestones are encountered in any street under construction, the Contractor shall remove them from the work site as City property. The cobblestones shall be neatly and securely placed on pallets so they can be moved about safely after delivery. The cobblestones shall be delivered, including off loading, to the lower lot at the Cesar Chavez Street Yard located at 2323 Cesar Chavez Street or where directed by the Engineer within the City of San Francisco. Contact Ms. Liz Lerma of the Bureau of Urban Forestry at (415) hours prior to delivery Portland Cement Concrete Paving

4 1.04 SUBMITTALS 2. The Contractor shall clean the cobblestones of dirt and exercise care in transporting the cobblestones so as to minimize damage. 3. Salvage, hauling and delivery of existing cobblestones to the designated areas from the project site shall be done as incidental work. A. The Contractor shall submit eight (8) copies of manufacturer s literature, specifications, applications and installations for Carbon Black (Gray or Charcoal Color); L.M Scofield C-24 Charcoal Gray ; QC Integral Colors IC-3 Ash Gray ; Solomon colors Charcoal Gray 920; or approved equal for curb ramps for the Engineer s approval. PART 2 PRODUCTS 2.01 MATERIALS 2.02 MIXES A. Portland Cement: In accordance with the requirements of Section of B. Aggregate: In accordance with the requirements of Sections , , , and of The contractor shall substitute recycled concrete for a portion of the virgin aggregate in an amount no less than 15% of the total dry aggregate mass. The recycled concrete material shall meet or exceed the specified requirements. When recycled material is used for concrete base, exposed concrete applications, such as, sidewalk, curb, gutter, parking strip, pavement, and curb ramp, the Sodium Sulfate Soundness test (ASTM C88) is waived. Recycled concrete material will not be allowed in structural concrete. C. Concrete Color: It shall be Gray or Charcoal in color, extra high strength, non-floating, dispersible, non-glare, permanent and unaffected by sunlight. It shall be composed of extremely fine-sub-micron particle size, and shall not create the loss of concrete strength. D. Cast-In-Place Detectable Surface Tiles: In accordance with the requirements of Section E. Surface Applied Detectable Surface Tiles: In accordance with the requirements of Section A. Concrete Curb: In accordance with the requirements of Section and of B. Combined Concrete Curb and Gutter: In accordance with the requirements of Section and of C. Concrete Sidewalk: In accordance with the requirements of Sections and of Portland Cement Concrete Paving

5 D. Concrete Base: Concrete for concrete base shall be Class /4, and contain the admixture 2 pounds calcium chloride per sack of cement ( and ) to accelerate the setting of the concrete in accordance with the requirements of Section 800 of E. Concrete Pavement: In accordance with the requirements of Sections , and of F. Curb Ramps: 1. Curb Portion of Work: In accordance with the requirements of Sections and of 2. Sidewalk Portion of Work: In accordance with the requirements of Sections and of 3. Curb Ramp Color: To obtain the approved permanent dark visual color contrast between the ramp and the adjacent sidewalk, add five (5) pounds of Carbon Black with a dispersing agent per cubic yard of concrete mix or use one of the following approved equal manufacturers and color types to match the Carbon Black color: 1) L.M. Scofield C-24 Charcoal Gray; 2) QC Integral Colors IC-3 Ash Gray ; 3) Solomon Colors Charcoal 920 ; 4) Carbon Black PART 3 EXECUTION 3.01 PREPARATION A. Preparation and Compaction of subgrade: In accordance with the requirements of Section 200 of 1. Concrete Curb: In accordance with the requirements of Section 202 of 2. Combined Concrete Curb and Gutter: In accordance with the requirements of Section 203 of 3. Concrete Sidewalk: In accordance with the requirements of Section 204 of 4. Concrete Base: In accordance with the requirements of Section 207 of 5. Concrete Pavement: In accordance with the requirements of Section 210 of 6. Concrete Curb Ramps: a. Curb Portion of Work: In accordance with the requirements of Sections 202 of Portland Cement Concrete Paving

6 b. Sidewalk Portion of Work: In accordance with the requirements of Section 204 of B. Preparation of subgrade to proper grade, excavating, backfilling, and compacting shall be considered as Incidental Work to the applicable bid items where excavation is required to perform the work. Asphalt shaving or grindings shall not be used as fill material. C. Saw cutting and removal of parking strip, concrete sidewalk, curb, gutter, roadway pavement and curb ramps to construct and/or reconstruct curb ramps, and to remove existing curb ramp shall be considered as Incidental Work to the applicable bid items where removal of said items are required to perform the work PROTECTION A. Concrete base shall not be allowed as a temporary wearing surface. Restored concrete base areas are to be temporarily filled with hot asphalt concrete to the level of adjacent existing pavement or gutter surface before opening to traffic INSTALLATION A. CONCRETE CURBS 1. Concrete Curb: In accordance with the requirements of Section 202 of 2. Placing Concrete: In accordance with the requirements of Section of 3. Construction Joints: In accordance with the requirements of Section of 4. Finishing: In accordance with the requirements of Section of 5. Protection and Curing: In accordance with the requirements of Section of 6. Repair and Replacement: In accordance with the requirements of Section of 7. Painting: In accordance with the requirements of Section of B. CONCRETE COMBINED CURBS AND GUTTER 1. Concrete Curb and Gutter: In accordance with the requirements of Section 203 of 2. Placing Concrete: In accordance with the requirements of Section of Portland Cement Concrete Paving

7 3. Construction Joints: In accordance with the requirements of Section and of 4. Finishing: In accordance with the requirements of Section of 5. Protection and Curing: In accordance with the requirements of Section of 6. Repair and Replacement: In accordance with the requirements of Section of 7. Painting: In accordance with the requirements of Section of C. CONCRETE SIDEWALK 1. Concrete Sidewalk: In accordance with the requirements of Section 204 of 2. Placing Concrete: In accordance with the requirements of Section of 3. Finishing: In accordance with the requirements of Section of 4. Joints: In accordance with the requirements of Section of 5. Protection and Curing: In accordance with the requirements of Section of 6. Sidewalk shall not be constructed monolithic with curb. 7. Street Names: In accordance with the requirements of Section of D. CONCRETE BASE 1. Concrete Base: In accordance with the requirements of Section 207 of 2. Placing Concrete: In accordance with the requirements of Section of 3. Construction Joints: In accordance with the requirements of Section of 4. Dummy Joints: In accordance with the requirements of Section of 5. Protection and Curing: In accordance with the requirements of Section of E. CONCRETE PAVEMENT Portland Cement Concrete Paving

8 1. Concrete Pavement: In accordance with the requirements of Section 210 of SSDPWSF, except that the pavement thickness shall be eight (8) inches unless otherwise noted. 2. Placing Concrete: In accordance with the requirements of Section of 3. Construction Joints: In accordance with the requirements of Section of 4. Dummy Joints: In accordance with the requirements of Section of 5. Protection and Curing: In accordance with the requirements of Section of F. CONCRETE CURB RAMP 1. Curb portion of work: In accordance with the requirements of Section 202 of 2. Sidewalk portion of work: In accordance with the requirements of Section 204 of 3. All curb ramps shall be poured separately from any adjacent construction, such as, curb, sidewalk or gutter. 4. Curb ramps shall be constructed in accordance with the requirements of the Standard Plans FIELD QUALITY CONTROL A. The City may test to satisfactorily demonstrate the proper drainage of the constructed curb and gutter work. The City will flush with water approximately 50 feet of the upstream end of each curb and gutter work for two minutes with minimum flow rate of 0.02 cubic feet per second or approximately 20 gallons equivalence. After five minutes, the Engineer and Contractor shall make visual inspection of gutter for ponding. B. Contractor shall make corrections necessary to demonstrate proper drainage and shall be considered Incidental Work and no separate payment will be made. The Contractor s correction method must be approved by the Engineer. The Engineer s approval does not release the Contractor from the successful execution of the remedy and the requirement to demonstrate proper drainage of the constructed curb and gutter work. END OF SECTION Portland Cement Concrete Paving