1. PURPOSE
1.1 This specification defines the minimum requirements for materials and installation of underground nonpressure gravity flow drainage systems.
2. SCOPE
2.1 The contractor shall furnish all labor, tools, materials, and equipment required for the complete installation of the storm, sanitary, and industrial wastewater gravity drainage systems. Installation shall be in accordance with current applicable local plumbing codes, standards, procedures, and the contract drawings and specifications. The contractor shall adhere to the local plumbing codes and shall inform Air Products of any discrepancies between the local codes and these specifications and contract drawings.
2.2 The work includes, but is not limited to, furnishing and installing all drainage piping, pipe fittings and appurtenances, concrete structures (such as manholes, catch basins, endwalls, septic tanks, and distribution boxes), excavation, shoring, backfill, and the testing and correction as required of the entire system.
2.3 The contractor shall support, safeguard, and protect from damage all existing service and utility lines and structures uncovered or encountered during all operations incident to this work. The location(s) of all existing utility and service lines uncovered during excavation, that have not been indicated on or have been incorrectly located on the contract drawings, shall be accurately identified in plan and elevation on a copy of the contract drawings and submitted to the Air Products representative.
3. RELATED DOCUMENTS
3.1 American Society for Testing and Materials (ASTM)
A48 Specification for Gray Iron Castings
A74 Specification for Cast Iron Soil Pipe and Fittings
A760 Specification for Corrugated Steel Pipe, Metallic-Coated for Sewers and Drains
A798 Practice for Installing Factory-Made Corrugated Steel Pipe for Sewers and Other Applications
A849 Specification for Post-Applied Coatings, Pavings, and Linings for Corrugated Steel Sewer and Drainage Pipe
A929 Steel Sheet, Metallic-Coated by the Hot-Dip Process for Corrugated Steel Pipe
C14 Specification for Nonreinforced Concrete Sewer, Storm Drain, and Culvert Pipe
C76 Specification for Reinforced Concrete Culvert, Storm Drain, and Sewer Pipe
C425 Specification for Compression Joints for Vitrified Clay Pipe and Fittings
C443 Specification for Joints for Concrete Pipe and Manholes, Using Rubber Gaskets
C478 Specification for Precast Reinforced Concrete Manhole Sections
C564 Specification for Rubber Gaskets for Cast Iron Soil Pipe and Fittings
C700 Specification for Vitrified Clay Pipe – Extra Strength, Standard Strength and Perforated
C923 Specification for Resilient Connectors Between Reinforced Concrete Manhole Structures, Pipes, and Laterals
D2235 Specification for Solvent Cement for Acrylonitrile Butadiene Styrene (ABS) Plastic Pipe and Fittings
D2321 Standard Practice for Underground Installation of Flexible Thermoplastic Sewer Pipe and Other Gravity Flow Applications
D2564 Specification for Solvent Cements for Poly (Vinyl Chloride) (PVC) Plastic Piping Systems
D2680 Specification for Acrylonitrile Butadiene Styrene (ABS) and Poly (Vinyl Chloride) (PVC) Composite Sewer Piping
D2751 Specification for Acrylonitrile Butadiene Styrene (ABS) Sewer Pipe and Fittings
D2855 Standard Practice for Making Solvent Cemented Joints with Poly (Vinyl Chloride) (PVC) Pipe and Fittings
D3034 Specification for Type PSM Poly (Vinyl Chloride) (PVC) Sewer Pipe and Fittings
D3138 Specification for Solvent Cements for Transition Joints Between Acrylonitrile-Butadiene- Styrene (ABS) and Poly (Vinyl Chloride) (PVC) Nonpressure Piping Components
D3212 Specification for Joints for Drain and Sewer Plastic Pipes Using Flexible Elastomeric Seals
F402 Standard Practice for Safe Handling of Solvent Cements, Primers, and Cleaners Used for Joining Thermoplastic Pipe and Fittings
F477 Specification for Elastomeric Seals (Gaskets) for Joining Plastic Pipe
F679 Specification for Poly (Vinyl Chloride) (PVC) Large Diameter Plastic Gravity Sewer Pipe and Fittings
F758 Specification for Smooth Wall Poly (Vinyl Chloride) (PVC) Plastic Underdrain Systems for Highway, Airport, and Similar Drainage
F913 Specification for Thermoplastic Elastomeric Seals (Gaskets) for Joining Plastic Pipe
F949 Specification for Poly (Vinyl Chloride) (PVC) Corrugated Sewer Pipe with a Smooth Interior and Fittings
3.2 U. S. Department of Labor – Occupational Safety and Health Administration (OSHA)
Occupational Safety and Health Standards for General Industry (29 CFR Part 1926)
4. MATERIALS
4.1 General
4.1.1 The contractor shall furnish and use materials that are high quality, free from defects and imperfections, of recent manufacture, unused, and of the classification and grade specified in the contract drawings and this specification.
4.1.2 Fittings shall be of manufacturers’ standard design. Fitting types include wye, 45 and 90 elbow, 90 bend (3 piece), lateral, reducer, tee, and cross. Special fittings may be fabricated if required to meet specific job requirements.
4.1.3 Flared pipe end sections manufactured to fit either round pipe or pipe arches shall be of manufacturers’ standard design.
4.1.4 Corrugated steel pipe shall not be used for the conveyance of sanitary and industrial wastes.
4.1.5 Only cast iron soil pipe shall be used within the limits of buildings and equipment foundations.
4.1.6 ABS plastic pipe and fittings shall not be used to convey liquids in excess of 80C (180F). PVC plastic pipe and fittings shall not be used to convey liquids in excess of 60C (140F). Steam condensate shall not be discharged into or conveyed by ABS or PVC plastic pipe.
4.2 Vitrified Clay Pipe and Fittings and Perforated Pipe
4.2.1 Pipe, perforated pipe, and fittings (standard strength) shall be in accordance with ASTM C700.
4.2.2 Jointing materials shall be in accordance with ASTM C425.
4.3 ABS and PVC Composite Sewer Pipe and Fittings
4.3.1 Pipe and fittings shall be in accordance with ASTM D2680.
4.3.2 Jointing materials as follows:
Solvent cement for ABS pipe shall be in accordance with ASTM D2235.
Solvent cement for PVC pipe shall be in accordance with ASTM D2564.
Solvent cement for ABS pipe to PVC pipe shall be in accordance with ASTM D3138.
Gaskets for PVC pipe shall be in accordance with ASTM F477 and F913.
4.4 Solid Wall ABS Sewer Pipe and Fittings
4.4.1 Pipe and fittings shall be in accordance with ASTM D2751 as follows:
SDR 35 for 75, 100, and 150 mm (3, 4, and 6 inch) nominal pipe sizes
SDR 42 for 200, 250, and 300 mm (8, 10, and 12 inch) nominal pipe sizes
where SDR is the average outside diameter divided by the minimum wall thickness.
4.4.2 Jointing materials as follows:
Solvent cement shall be in accordance with ASTM D2235.
Gaskets shall be in accordance with ASTM F477.
4.5 Solid Wall PVC (4 to 15 inch nominal pipe sizes) Sewer Pipe and Fittings
4.5.1 Pipe and fittings for nominal pipe sizes 100, 150, 200, 250, 300, and 375 mm (4, 6, 8, 10, 12, and 15 inches) shall be SDR 35 in accordance with ASTM D3034.
4.5.2 Jointing materials as follows:
Solvent cement shall be in accordance with ASTM D2564.
Gaskets shall be in accordance with ASTM F477.
4.6 Solid Wall PVC (18 to 36 inch nominal pipe sizes) Sewer Pipe and Fittings
4.6.1 Pipe and fittings for nominal pipe sizes of 450, 525, 600, 675, 750, 825, and 900 mm (18, 21, 24, 27, 30, 33, and 36 inches) shall be in accordance with ASTM F679.
4.6.2 Gaskets shall be in accordance with ASTM F477.
4.7 PVC (Corrugated Wall) Perforated and Unperforated Sewer Pipe and Fittings
4.7.1 Pipe shall be in accordance with ASTM F949.
4.7.2 Fittings shall be in accordance with ASTM F949 or SDR 35 pipe meeting the requirements of ASTM D3034 or F679.
4.7.3 Jointing materials as follows:
Solvent cement shall be in accordance with ASTM D2564.
Gaskets shall be in accordance with ASTM F477.
4.8 PVC Smooth Wall Underdrain and Fittings
4.8.1 Pipe (Type PS28) shall be in accordance with ASTM F758.
4.8.2 Fittings shall be in accordance with ASTM D3034.
4.8.3 Jointing materials as follows:
Solvent cement shall be in accordance with ASTM D2564.
Gaskets shall be in accordance with ASTM F477.
4.9 Nonreinforced Concrete Pipe
4.9.1 Pipe for nominal pipe sizes 100, 150, 200, and 250 mm (4, 6, 8, and 10 inches) shall be Class I, in accordance with ASTM C14, with bell and spigot or tongue and groove joints.
4.9.2 Gaskets shall be in accordance with ASTM C443.
4.10 Reinforced Concrete Pipe
4.10.1 Pipe for nominal pipe sizes 300 mm through 2400 mm (12 inches through 96 inches) shall be Class II – Wall A – 27.6 MPa (4000 psi), in accordance with ASTM C76, with bell and spigot or tongue and groove joints.
4.10.2 Pipe for nominal pipe sizes 2550 mm through 3600 mm (102 inches through 144 inches) shall be Class II – Wall A – 34.5 MPa (5000 psi), in accordance with ASTM C76, with bell and spigot or tongue and groove joints.
4.10.3 Gaskets shall be in accordance with ASTM C443.
4.11 Cast Iron Soil Pipe and Fittings
4.11.1 Pipe shall be service weight, hub and spigot ends and coated in accordance with ASTM A74.
4.11.2 Rubber gaskets shall be in accordance with ASTM C564 and caulked when required by the governing plumbing code.
4.12 Corrugated Steel Pipe and Fittings
4.12.1 Pipe shall be in accordance with ASTM A760 as follows:
Full Circular – Type I
Pipe Arch – Type II
Perforated – Type III
4.12.2 Base material and coatings shall be in accordance with ASTM A929.
4.12.3 Post applied coating shall be in accordance with ASTM A849, fully asphalt coated – Class B.
5. PRECAST REINFORCED CONCRETE MANHOLES
5.1 Sections
5.1.1 Precast reinforced concrete manhole base sections, riser sections, and appurtenances such as grade rings, tops, and special sections shall be wet cast type conforming to ASTM C478. Components shall be mechanically vibrated during manufacture to render a high density concrete to ensure against groundwater infiltration through the walls. Dry cast components will not be accepted. The minimum compressive strength of the concrete in the manhole base, riser, and top sections shall be 27.6 MPa (4000 psi).
5.1.2 Manholes shall have a minimum inside dimension of 1200 mm (48 inches). When circular manholes are used, cone sections shall be eccentric. The base riser section shall be cast with an integral floor. Flat slab tops shall be furnished when the manhole depth precludes the use of cone sections. The access opening in the cone shall be a minimum of 600 mm (24 inches) in diameter. Box-type manhole sections may also be used if this type of unit is economical and available in the particular geographical area. The opening in the top slab shall be eccentric.
5.1.3 Joints between circular sections shall be made with rubber O-ring gaskets conforming to ASTM C443.
5.1.4 The invert channels shall be formed in the base of the manhole with field-placed concrete. The channel shall be smooth and semicircular in shape conforming to the inside of the pipe section. Changes in direction of flow shall be made with a smooth curve of as large a radius as the size of the manhole will permit. Changes in size and grade of the channels shall be made gradually and evenly. The floor of the manhole outside of the channels shall be smooth and shall slope toward the channel at 25 mm (1 inch) fall in 300 mm (12 inches) of run.
5.1.5 All exterior surfaces of manholes conveying sanitary and industrial wastewater shall be damp proofed with two shop-applied coats (15 to 18 MDFT per coat) of Koppers Bitumastic No. 50 as manufactured by the Koppers Company, Inc., Pittsburgh, PA 15219.
5.2 Pipe Connections
5.2.1 Storm sewer pipe connections to precast concrete manholes shall be grouted in place. Openings cast into the walls of the base section shall be of a size which will accommodate the insertion of the penetrating pipe and allow annular space [(minimum of 50 mm (2 inches)] for the installation of a nonshrink cementitious grout seal. Grout shall be a packaged, premixed, inorganic, nonmetallic aggregate, and cement-based mortar.
5.2.2 Sanitary and industrial wastewater pipe connections to precast manholes shall be made with resilient connectors conforming to ASTM C923. The mechanical resilient seal system shall be equal to the PSX Positive Seal Connector as manufactured by the Press Seal Gasket Corporation – Concrete Products Supply Company, P.O. Box 10482, Fort Wayne, IN 46852. Openings cast into the wall of the base section shall be of the size recommended by the pipe seal manufacturer based upon the pipe material, pipe size, and type of connector.
5.3 Steps
5.3.1 Manhole steps shall be manufactured from gray iron, Class Number 35B conforming to ASTM A48. Steps shall be equal to Item No. R-1981-I manufactured by Neenah Foundry Company, Neenah, WI. Steps shall be cast in place during manhole manufacture.
5.3.2 The steps in riser and conical top sections shall be aligned in each section so as to form a continuous ladder with steps equally spaced vertically in the assembled manhole at a maximum distance of 400 mm (16 inches apart). The minimum clear distance between the step and the opposite wall of the manhole riser or cone shall be 450 mm (18 inches) as measured at the center face of the step.
5.4 Frame and Grate
5.4.1 The manhole frame and grate shall be manufactured from gray iron, Class Number B conforming to ASTM A48. The casting shall be capable of supporting a H20 wheel load of 34.5 N (16,000 pounds). The strength category shall be heavy duty. All horizontal surfaces shall be machined.
5.4.2 Storm sewer manhole frame with solid type “B” lid shall be equal to Item No. R-1642 as manufactured by Neenah Foundry Company. The access opening shall be 600 mm (24 inches) in diameter. The words “STORM SEWER” shall be cast in the lid. Anchor holes 25 mm (1 inch) in diameter on a 838 mm (33-inch) bolt circle (total four holes) shall be provided in the manhole frame base.
5.4.3 Sanitary and industrial wastewater manhole frame with solid type “B” self-sealing lid shall be equal to Item No. R-1642 as manufactured by Neenah Foundry Company. The self-sealing feature shall consist of a gasket material factory installed into a machined dovetail groove on the bearing surface of the lid. The words “SANITARY SEWER” or “IND. WASTE SEWER” shall be cast into the lid as appropriate.
5.4.4 A compressible, permanently flexible, preformed butyl rubber joint sealant shall be placed between the uppermost precast manhole section and the manhole frame to provide a watertight joint. The sealant shall be 9.5 mm (3/8 inch) thick (minimum) before compression. The sealant shall extend under the full bearing area of the frame base. The material shall be equal to E-Z Stik All-Weather Butyl Sealant distributed by Concrete Products Supply Company, Fort Wayne, IN.
5.4.5 All frames shall be anchored to the top of circular precast manhole section with four Hilti HVA Adhesive Anchors of 20 mm (3/4 inch) diameter. Predrill the hole in the precast concrete to the diameter and depth as specified by the anchor manufacturer. Frames in square section cover slabs shall be cast in place.
6. PRECAST REINFORCED CONCRETE CATCH BASINS
6.1 Sections
6.1.1 Precast reinforced concrete catch basin sections shall meet the requirements specified in paragraphs 5.1.1, 5.1.2, 5.1.3, and 5.1.4.
6.2 Pipe Connections
6.2.1 Pipe connections shall meet the requirements specified in paragraph 5.2.1.
6.3 Steps
6.3.1 Catch basin steps shall meet the requirements specified in paragraphs 5.3.1 and 5.3.2.
6.4 Frame and Grate
6.4.1 The catch basin frame and grate shall meet the requirements specified in paragraphs 5.4.1, 5.4.4, and 5.4.5.
6.4.2 Storm sewer manhole frame with type “F” grate shall be equal to Item No. R-2370 as manufactured by Neenah Foundry Company. The access opening shall be 600 mm (24 inches) in diameter. The grate shall have a minimum open area of 1.3 square feet. Anchor holes
25 mm (1 inch) in diameter on a 838 mm (33-inch) bolt circle (total four holes) shall be provided in the manhole frame base for circular section applications.
7. TRENCHING, BEDDING, AND BACKFILL
7.1 The contractor shall perform all excavation, shoring, backfilling, and compaction required for the installation of the underground drainage systems.
7.2 All excavations 1.2 m (4 ft) in depth or greater into which personnel may be allowed to enter shall be shored, benched, and/or sloped to comply with the current requirements of OSHA. Special care shall be taken to satisfy any “confined space” requirements.
7.3 Heavy construction equipment, building materials, excavated soil, and vehicular traffic shall not be allowed within a horizontal distance from the top of the excavation equal to 1/3 of the excavation depth for sloped wall excavations and 1/2 of the excavation depth for shored wall excavations. Temporary excavations adjacent to existing foundations shall not extend below a plane projected downward at a 45 angle from the closest edge of the foundation.
7.4 Trench bottoms shall have the proper uniform grade in the direction of the flow as shown on the drawings. To ensure sufficient room for installation, the width of the trenches at any point below the top of the pipe shall not be less than the outside diameter of the pipe plus 300 mm (12 inches). It is important to have sufficient space that permits satisfactory jointing and thorough tamping of the bedded material under and around the pipe. The bedding surface for the pipe shall provide a firm foundation of uniform density throughout the entire length of the pipe. The pipe shall be carefully bedded in a sand or soil foundation that has been shaped accurately and rounded to conform to the lowest 1/4 of the outside portion of the circular pipe. Bell holes and depressions for joints shall be only of such length, depth, and width as required for properly making the joint.
7.5 Rock in either ledge or boulder formation shall be removed and replaced with a bedding of sand or gravel material to provide a compacted cushion having a minimum thickness of 200 mm (8 inches) between the rock and the bottom of the pipe. Where bell and spigot pipe is used, the cushion shall be maintained under the straight portion of the pipe.
7.6 Where the bottom of the trench is found to be unstable or to include ashes, cinders, any type of refuse, vegetable, or other organic matter, the contractor shall excavate and remove such unsuitable material to the width and depth directed by the Air Products representative. Before the pipe is placed, the trench shall be backfilled to the proper grade with a borrow of sand or gravel and compacted properly.
7.7 When the pipe is placed in an area of the site that requires fill to establish the proposed final grade, the fill shall be properly compacted to the requirements indicated on the drawings prior to the commencement of the trench excavation. Pipe installed prior to fill compaction will not be accepted.
7.8 The pipe trenches shall be cleaned of all trash and debris after the pipes have been tested and inspected and before backfilling occurs.
7.9 Material for backfilling shall consist of the excavated soils or borrow of sand or gravel or other specified structural fill material. No cinders shall be used for backfill. Backfill shall be placed in horizontal layers, not exceeding 150 mm (6 inches) in thickness. Each layer shall be compacted to the requirements indicated on the drawings.
7.10 Excess excavated material shall be disposed of either on the site or removed from the site and disposed of in a legal manner, as directed by the Air Products Representative and without additional cost to Air Products.
8. PIPE INSTALLATION
8.1 All pipe shall be carefully examined before placement. Defective or damaged pipe shall not be used.
8.2 Pipe shall not be placed when a trench contains water or when weather conditions are unsuitable for such work. The contractor is responsible for the diversion of drainage and for dewatering of trenches during construction.
8.3 The open ends of all pipes shall be securely closed at times when work is not in progress to prevent trench water, earth, or other substances from entering the pipe.
8.4 Pipe placement shall proceed upgrade with the open ends of the bell and spigot pipe pointing in the direction of the flow. Each pipe shall be placed true to line and grade and in such a manner as to provide a close, concentric joint with the adjoining pipe and to prevent sudden offsets of the flow line. As the work progresses, the interior of the line shall be kept clean and free of all dirt and superfluous materials.
8.5 Header and branch line connections shall be made with the appropriate fittings for the condition. Cutting pipe to make connections is only permitted when required to tie into an existing system.
8.6 Underground installation requirements of plastic pipe for sewers and other gravity flow applications shall be in accordance with ASTM D2321 which describes in detail trench excavation, bedding, and pipe installation.
8.7 Solvent cemented joints in plastic pipe shall be made following the procedures specified in
ASTM D2855. Joints in drain and gravity sewer plastic pipe with internal or external pressures less than 7.6 m (25 ft) head may utilize flexible, elastomeric seals placed in accordance with
ASTM D3212.
8.8 Solvent cements used for plastic pipe joints are made from flammable liquids and shall be kept away from sources of ignition. Refer to ASTM F402 for safe handling of solvent cements used for both ABS and PVC pipe and fittings.
8.9 Underground installation requirements of corrugated steel pipe shall be in accordance with ASTM A798 which describes in detail trench excavation, bedding, pipe installation, and backfill.
9. INSPECTION
9.1 All materials and workmanship shall be subject to inspection and examination by the Air Products representative. Any defective material or workmanship shall be corrected to the Air Products representative’s satisfaction. Any such work shall be at the contractor’s expense.
10. TESTING
10.1 General
10.1.1 The entire gravity drainage and vent systems that are part of this contract shall be tested with water or air, as directed by the Air Products representative and in accordance with the local, state, and federal regulations, and shall be proven to be satisfactory in all respects before the trenches are backfilled. All items such as testing instruments, force pumps, and gauges shall be provided by the contractor.
10.1.2 When applicable, the drainage system shall be inspected by the local plumbing inspector. The contractor shall make all the necessary arrangements for inspection by the local authorities. Testing in this case shall be as directed by the plumbing inspectors.
10.1.3 All defects revealed by the specified tests shall be corrected by repair or replacement without additional cost to Air Products.
10.1.4 The contractor shall secure and submit to the Air Products representative a certificate of compliance with all requirements of the applicable plumbing code. This requirement shall be fulfilled prior to final acceptance by Air Products.
10.2 Water Test
10.2.1 The water test shall be applied to the drainage and vent systems either in its entirety or in sections. If applied to the entire system, all openings in the piping shall be tightly closed, except the highest opening, and the system filled with water to the point of overflow. If the system is tested in sections, each opening shall be tightly plugged except the highest opening of the section under test, and each section shall be filled with water, but no section shall be tested with less than 3 m (10 ft) head of water. When testing successive sections, at least the upper 3 m (10 ft) of the preceding section shall be tested, so that no joint or pipe in the building [except the uppermost 3 m (10 ft) of the system] shall have been submitted to a test of less than 3 m (10 ft) head of water.
10.2.2 The water shall be kept in the total system, or in the portion of the system to be tested, for at least 15 minutes before any testing or system inspection starts. The system shall then be watertight at all joints.
10.3 Air Test
10.3.1 The air test shall be made by attaching air compressor testing apparatus to any suitable opening and, after closing all other inlets and outlets to the system, forcing air into the system until the uniform gauge pressure of .35 kg/cm2g (5 psig) or sufficient to balance a column of mercury 250 mm (10 inches) in height. The pressure shall be held without the introduction of additional air for a period of at least 15 minutes.
10.3.2 Air testing of ABS and PVC plastic solid wall or ABS and PVC composite sewer pipe and fittings is prohibited due to potential hazards of brittle fracture of exposed piping.