SECTION SANITARY SEWER SYSTEM

Transcription

1 SECTION SANITARY SEWER SYSTEM PART 1 GENERAL 1.01 SUMMARY A. Section Includes: Sanitary sewer system including necessary accessories indicated on drawings and specified in this section. Contractor shall include in his bid price any amount imposed by the utility company having jurisdiction to connect into the existing sanitary system. B. Related Sections: Excavating, Backfilling, and Compaction for Utilities Cast-in-Place Concrete. 3. Division 15 - Mechanical Work REFERENCES A. American Society for testing and Materials (ASTM): 1. A74-96 Specification for Cast Iron Soil Pipe and Fittings. 2. C Specification for Compression Joints for Vitrified Clay Pipe and Fittings. 3. C564-95a Specification for Rubber Gaskets for Cast Iron Soil Pipe and Fittings. 4. C Specification for Vitrified Clay Pipe, Extra Strength, Standard Strength, and Perforated. 5. D (95) Practice for Underground Installation of Thermoplastic Pipe for Sewers and Other Gravity-Flow Applications. 6. D Specification for Type PSM Poly (Vinyl Chloride) (PVC) Sewer Pipe and Fittings. 7. D a Specification for Joints for Plastic Pressure Pipes Using Flexible Elastomeric Seals. 8. F477-96a Specification for Elastomeric Seals (Gaskets) for Joining Plastic Pipe. B. Cast Iron Soil Pipe Institute. C. Standard Plumbing Code (SPC) SUBMITTALS Project No. SPECIFICATION GUIDELINES

2 A. Submit properly identified manufacturer's literature including data on pipe before starting work. B. Submit test reports and certificates for approval. 1. Certificate: Submit manufacturer's certificate of compliance or certified analysis according to applicable standards for each shipment of materials PRODUCT STORAGE A. Store materials on site, and keep clean and free of foreign materials. Any damaged items shall be replaced at no additional cost to the Board. PART 2 PRODUCTS 2.01 MATERIALS A. Pipe and Fittings: 1. Vitrified Clay Pipe and Fittings: Comply with ASTM C700 and except where indicated otherwise on the drawings, use extra strength bell and spigot type. 2. Polyvinyl Chloride (PVC) Sewer Pipe and Fittings: a. Comply with ASTM D3034 for SDR35 and except where indicated otherwise on the drawings. Use bell and spigot type pipe. b. The pipe shall be colored with a different color from water pressure pipe and force main for in ground identification as sewer pipe. 3. Cast Iron Soil Pipe and Fittings: Comply with ASTM A74 for cast iron soil pipe and fittings. B. Pipe Joints: 1. Vitrified clay pipe for vitrified clay pipe joints made with precast factory applied plastic joints shall comply with ASTM C425, Type I or Type III. 2. PVC Sewer Pipe: Elastomeric gasket joints providing a watertight seal. 3. Cast Iron Soil Pipe and Fittings: Furnish with roll-on joints complying with ASTM C564 and Cast Iron Pipe Institute Recommendations for Compression Joints. Project No. SPECIFICATION GUIDELINES

3 C. Manholes: Cast in place concrete or precast concrete with round cast iron frames and covers as indicated on drawings and as specified in Section "Cast-in-Place Concrete". D. Cleanouts: Commercially manufactured wye branches and as indicated on drawings. PART 3 EXECUTION 3.01 INSPECTION A. Do not proceed with the work of this section until conditions detrimental to the proper and timely completion of the work have been corrected in an acceptable manner LOCATION A. Where location of sewer is not clearly defined, do not locate sewer closer horizontally than 10 feet to a water supply main or service line, except that where bottom of water pipe will be at least 18 inches above top of sewer pipe. Horizontal spacing may be a minimum of 6 feet within M-DCPS property. 1. Where gravity-flow sewers cross above waterlines, fully encase sewer pipe for a distance of 10 feet on each side of crossing in concrete or provide acceptable pressure pipe with no joint closer horizontally than 3 feet to crossing. 2. The thickness of the concrete encasement including that at the pipe joints shall be not less than 4 inches. B. Excavation and backfilling for trenches and manholes shall be as specified in Section Excavating, Backfilling, and Compacting for Utilities INSTALLATION A. Placing Pipe: 1. Shape bottom of trench by hand to give uniform circumferential support to the lower fourth of each pipe. 2. Where applicable, pipe laying shall proceed upgrade with tongue or spigot ends pointing in direction of flow. 3. Lay each pipe true to line and grade indicated on drawings and in such manner to form a close concentric joint with adjoining pipe and to prevent sudden offsets Project No. SPECIFICATION GUIDELINES

4 of flow line. 4. As work progresses, clean interior of sewer of dirt and superfluous materials. a. Where cleaning after laying is difficult because of small pipe size, a suitable swab or drag shall be kept in the pipe and pulled forward past each joint immediately after joint has been completed. b. If maximum width of trench at top of pipe as specified is exceeded, install either concrete cradling, pipe encasement or other bedding as may be required to support added load of backfill. 5. Keep trenches for all sections of sewer free from water until the pipe-jointing has set and trench backfilled. a. Do not lay pipe when condition of trench or weather is unsuitable for such work. 6. At time is not in progress, keep open end of pipes and fittings securely closed. B. Pipe Joints: a. When conditions prevent pipe from being adequately supported on undisturbed earth or tamped backfill, encase the pipe in concrete or support it on a concrete cradle. b. Pipe and fittings shall be installed according to ASTM D Vitrified Clay Pipe: Install joints according to ASTM C425 for compression joints. 2. Polyvinylchloride (PVC) Pipe: Install joints according to ASTM D3212 and approved manufacturer's installation procedures. 3. Cast Iron Soil Pipe: Install roll-on joints according to Cast Iron Soil Pipe Institute for compression joints. C. Manholes: 1. Construction: As indicated on drawings and as specified in Section Excavating, Backfilling and Compacting for Utilities. a. Frames and Covers: Set the cast iron frames and covers in a bed of mortar and carefully adjust to elevations shown on drawings. Project No. SPECIFICATION GUIDELINES

5 D. Cleanouts: Install commercially manufactured wye branches where indicated on the drawings. Cutting into pipe for connection will not be allowed except in special cases when accepted by the A/E. E. Pipe Connections to Existing Structures: Make finished work to comply as nearly as practicable to essential applicable requirements for new structures, including all necessary concrete work, cutting, and shaping. Coordinate work with utility company having jurisdiction TESTING AND INSPECTION A. Inspect sewer lines by checking each section for alignment. 1. A full circle of light shall be seen by looking through the pipe at a light held at opposite end of the section of sewer line being inspected. 2. Make any corrections required in line or grade. B. Leakage Tests: 1. Test lines for leakage by either infiltration tests or exfiltration tests, as appropriate. 2. Backfill trench before testing for leakage, up to at least the lower half of pipe. 3. If required, place sufficient additional backfill to prevent pipe movement during testing, leaving joints uncovered to allow inspection. 4. Correct visible leaks encountered regardless of leakage test results. 5. Measure infiltration when water table is two feet or more above top of pipe at upper end of pipe line section to be tested, using a suitable weir or other acceptable device. 6. When infiltration cannot be properly tested, an exfiltration test shall be made by filling the line to be tested with water so that a head of at least 2 feet is provided above both water table and top of pipe at the upper end of pipe to be tested. 7. Allow filled line to stand until pipe has reached its maximum absorption, but not less than 4 hours. After absorption, reestablish the head. 8. The amount of water required to maintain this water level during a 2-hour test or exfiltration test shall not exceed 0.4 gallons/inch diameter per 100 feet of pipe line per hour. 9. When leakage exceeds maximum amount specified, satisfactory correction shall be made and retesting accomplished. Project No. SPECIFICATION GUIDELINES

6 10. Testing, correction and retesting shall be made at no additional cost to the Board. END OF SECTION Project No. SPECIFICATION GUIDELINES