A. 
Description.
(1) 
The work of this article includes, but is not limited to:
(a) 
Precast concrete manhole sections.
(b) 
Precast concrete manhole bases.
(c) 
Cast-in-place concrete manhole bases.
(d) 
Manhole steps.
(e) 
Manhole frames and covers and adjusting rings.
(2) 
Related work specified elsewhere:
(a) 
Trenching, backfilling and compacting: Article VII.
(b) 
Soil erosion and sediment pollution control: Article IX.
(c) 
Finish grading, seeding and sodding: Article X.
(d) 
Bituminous paving and surfacing: Article XI.
(e) 
Sanitary sewer pipe: Article XVII.
(f) 
Storm drain pipe: Article XIX.
(g) 
Sewer testing: Article XXII.
(h) 
Plain and reinforced cement concrete: Article XXVII.
(i) 
Cement concrete for utility construction: Article XXVIII.
(3) 
Definitions. As used in this article, the following terms shall have the meanings indicated:
SHALLOW MANHOLE
Manhole with vertical height from top of base to top of rim less than five feet.
STANDARD MANHOLE
Manhole with vertical height from top of base (invert) to top of rim greater than five feet.
(4) 
Applicable Standard Details.[1]
(a) 
DT 02601-1, Cast-in-Place Manhole Base Detail.
(b) 
DT 02601-2, Precast Manhole Base Detail.
(c) 
DT 02601-3, Standard Manhole Detail.
(d) 
DT 02601-4, Shallow Manhole Detail.
(e) 
DT 02601-5, Drop Connection Detail.
[1]
Editor's Note: Said Standard Details are included as an attachment to this chapter.
B. 
Quality assurance.
(1) 
Reference standards.
(a) 
Pennsylvania Department of Transportation (PennDOT), latest revision:
[1] 
Publication 408, Specifications.
[2] 
Publication 203, Work Zone Traffic Control.
[3] 
Publication RR-459, Occupancy of Highways by Utilities.
[4] 
Publication 19, Field Test Manual.
[a] 
PTM No. 106 - Moisture-Density Relations of Soils (using five-point-five-pound Rammer and twelve-inch drop).
[b] 
PTM No. 402 - Determining In-Place Density and Moisture Content of Construction Materials by Use of Nuclear Gauges.
[5] 
Publication 72M, Roadway Construction Standards (RC-39).
(b) 
American Society for Testing and Materials (ASTM).
[1] 
A48, Specification for Gray Iron Castings.
[2] 
A185, Specification for Welded Steel Wire Fabric, Plain, for Concrete Reinforcement.
[3] 
A615, Specification for Deformed and Plain Billet-Steel Bars for Concrete Reinforcement.
[4] 
B221, Specification for Aluminum and Aluminum Alloy Extruded Bars, Rods, Wire, Profiles and Tubes.
[5] 
C139, Specification for Concrete Masonry Units for Construction of Catch Basins and Manholes.
[6] 
C270, Specification for Mortar for Unit Masonry.
[7] 
C443, Specification for Joints for Circular Concrete Sewer and Culvert Pipe, Using Rubber Gaskets.
[8] 
C478, Specification for Precast Reinforced Concrete Manhole Sections.
[9] 
C923, Specification for Resilient Connectors Between Reinforced Concrete Manhole Structures, Pipes and Laterals.
[10] 
D1248, Specification for Polyethylene Plastics Molding and Extrusion Materials.
(c) 
Federal specifications (FS): SS-S-00210, Sealing compound, preformed plastic, for expansion joints and pipe joints.
(2) 
Inspections.
(a) 
Inspections of the manholes by the municipality will, at a minimum, be made of materials upon delivery to the job site; of the subgrade, prior to manhole base construction or placement; and of the completed manhole, prior to backfill.
(b) 
Inspections of the frame and covers by the municipality will be made upon delivery to the job site; and of the completed installation, prior to backfill.
(c) 
A final inspection of the manhole channels, steps, frames and covers, and all joints will be performed upon completion of all testing, roadway restoration, and/or seeding.
(d) 
Manholes shall be subject to rejection for failure to conform with these specifications or if any one of the following conditions is noted:
[1] 
Fractures or cracks passing through the wall, except for a single end crack that does not exceed the depth of the joint.
[2] 
Defects that indicate incorrect proportioning, mixing, and molding.
[3] 
Surface defects larger than one-half-inch diameter indicating honey-combed or open texture.
[4] 
Damaged or cracked ends, where such damage would prevent making a satisfactory joint.
[5] 
Any continuous crack having a surface width of 0.01 inches or more and extending for a length of six inches or more, regardless of position in the section wall.
(3) 
Concrete testing (for cast-in-place work): as specified in Article XXVII.
C. 
Submittals.
(1) 
Certificates. Submit two copies of certification from material suppliers attesting that materials meet or exceed specification requirements.
(2) 
Shop drawings.
(a) 
Submit details of manhole sections, and precast bases if used.
(b) 
Submit details of manhole frames and covers, including required lettering.
(c) 
Submit details of adjusting rings.
(d) 
Submit details of manhole steps.
(e) 
Submit manufacturer's descriptive literature for the pipe to manhole flexible connections.
(f) 
Submit manufacturer's descriptive literature for joint-sealant compounds.
D. 
Job conditions: as specified in Article VII.
E. 
Product delivery, storage and handling.
(1) 
Precast concrete units.
(a) 
After fabrication and curing, transport the manhole and components to the job site. Protect until required for installation.
(b) 
Handle to avoid damage to surfaces, edges and corners and to avoid creation of stresses within the units.
A. 
Crushed stone base: AASHTO No. 57, Type C crushed stone or gravel aggregate, Section 703.2, Publication 408 Specifications. Do not use slag or cinders.
B. 
Manhole brick: not permitted.
C. 
Concrete masonry units: not permitted.
D. 
Cement mortar: ASTM C270, Type S.
E. 
Cement concrete: Article XXVIII.
F. 
Rubber gaskets: ASTM C443.
G. 
Resilient pipe-to-manhole connection: ASTM C923. PSX gaskets as manufactured by Press-Seal Gasket Corporation, Fort Wayne, Indiana, or approved equal.
H. 
Nonshrink grout: fastsetting, cement-based mortar such as Waterplug, manufactured by Thoro Division of ChemRex, Shakopee, MN, or approved equal.
I. 
Precast concrete manhole bases and sections: ASTM C478.
(1) 
Five-point-five-percent ± 1.5% air-entrained cement concrete.
(2) 
Eccentric cone or flat slab top sections; minimum twenty-four-inch access opening.
(3) 
Precast riser sections of length to suit.
(4) 
Precast bases of a design similar to the precast riser sections.
(5) 
Precast drop connections, and precast lampholes are not permitted.
(6) 
Manholes shall have a four-foot inside diameter unless otherwise noted on the drawings.
(7) 
Precast manhole bases shall be manufactured in accordance with the elevations shown on the municipality's grade sheets and shall accommodate lateral hookups as marked in the field.
(8) 
Precast manhole bases and precast concrete channels shall be constructed specifically for the work intended.
J. 
Glass fiber-reinforced polyester manholes: not permitted.
K. 
Joint sealant compound: FS SS-S-00210, preformed, flexible, self-adhering, cold-applied. Joints between manhole base and riser, between risers, between riser and cone, between cone and adjusting rings and cast-iron frame, shall be made of RUB'R-NEK, a flexible plastic gasket-type sealant manufactured by K. T. Snyder Company, Inc., of Houston, Texas, or approved equal.
L. 
Manhole steps. Manhole steps shall be made of noncorrosive aluminum, or steel reinforced fiberglass or polypropylene materials. Steps in precast walls shall terminate one-inch from outer surface and shall be cast in place wherever possible or grouted with a waterproof, nonshrink grout.
(1) 
Aluminum alloy steps (Alloy 6061-T6) shall be Model No. F-140, manufactured by Washington Aluminum Company, Inc., of Baltimore, MD, or approved equal and shall have a protective coating consisting of asphalt coating conforming to AASHTO M-190 requirements applied to the portion to be embedded in the concrete.
(2) 
Steel reinforced fiberglass steps shall be Model No. 115 manufactured by R.J. Manufacturing, Inc., of San Antonio, Texas, or approved equal.
(3) 
Steel reinforced copolymer polypropylene plastic steps shall be Model No. PS-2-B or PS-2-PFS, manufactured by M. A. Industries, Inc., of Peachtree City, Georgia, or approved equal.
M. 
Manhole frames and covers.
(1) 
Domestic soft, gray cast-iron castings: ASTM A48, Class 35B or better; free of bubbles, sand and air holes, and other imperfections. Castings shall be furnished unpainted.
(2) 
Frames and covers shall be capable of withstanding an AASHTO HS-25 loading and shall have a minimum twenty-one-inch clear opening. Watertight frames and covers shall meet AASHTO HS-20 loading requirements.
(3) 
Frame and cover shall have machined bearing surfaces and shall be matched to insure against rocking.
(4) 
Cover shall be lettered or marked "sanitary sewer" or "storm sewer" as appropriate.
(5) 
Standard frames and covers shall be similar to Model No. 1835 manufactured by East Jordan Iron Works, Inc., or Model 1255B manufactured by Bridgestate Foundry Corp., or approved equal. Manhole cover shall be three inches thick. Covers shall be self-sealing, have two concealed watertight pick holes, and shall have two lifting rings or bars, and no openings to permit surface water entry.
(6) 
Watertight frames and covers shall have suitable clamp, employing a rubber gasket seal, similar to Model No. 1120Z1 manufactured by East Jordan Iron Works, Inc., or Model 1032 manufactured by Bridgestate Foundry, or approved equal.
N. 
Reinforcing steel: Article XXVII.
O. 
Adjusting rings.
(1) 
Precast cement concrete grade adjustment rings shall be cast from 4,000 psi concrete (twenty-eight-day compressive strength) and shall be a maximum of two inches thick per ring. Circumferential reinforcement shall be in conformance with ASTM C478. Split concrete rings are not permitted.
(2) 
Plastic adjusting rings shall be injection molded high density polyethylene (HDPE) conforming to ASTM D1248 as manufactured by Ladtech, Inc., Lino Lakes, MN. Maximum ring thickness shall be two inches. Plastic rings must be approved by the municipality prior to use.
(3) 
Metal adjusting rings are not permitted without prior approval of the Engineer.
P. 
Wall penetration seals.
(1) 
Concrete wall penetration seals shall be Link-seal as manufactured by Thunderline Corporation, Houston, TX, or approved equal.
(2) 
Use appropriate wall-sleeve type as recommended by manufacturer to provide watertight seal/connection.
A. 
Maintenance and protection of traffic: Article VII.
B. 
Cutting paved surface prior to excavation: Article VII.
C. 
Blasting: Article VII.
D. 
Excavation.
(1) 
Excavate as specified in Article VII.
(2) 
Excavate at location marked in the field.
(3) 
Excavate to the required depth and grade for the invert of the manhole, plus that excavation necessary for placement of base material.
E. 
Standard manhole construction.
(1) 
All manholes greater than five feet in vertical height from top of base to top of rim.
(2) 
Install a minimum of four-inch thick compacted crushed stone base. Provide cast-in-place concrete or precast concrete bases.
(a) 
Construct cast-in-place bases as shown on Standard Detail DT 02601-1.[1] Cast-in-place bases may be constructed with a special form for a joint to match the manhole cylinder sections.
[1]
Editor's Note: Said Standard Detail is included as an attachment to this chapter.
(b) 
Install precast bases as shown on Standard Detail DT 02601-2.[2]
[1] 
Set the precast base on the crushed stone base.
[2] 
Provide a sealed, flexible resilient connection between pipe and precast base section.
[2]
Editor's Note: Said Standard Detail is included as an attachment to this chapter.
(3) 
Install the proper diameter watertight manholes on precast concrete or poured-in-place concrete bases shown on the drawings.
(4) 
Construct drop connections shown on Standard Detail DT 02601-5.[3] Encase drop connection in concrete.
[3]
Editor's Note: Said Standard Detail is included as an attachment to this chapter.
(5) 
Form flow channels in manhole bases. Slope channels uniformly from influent invert to effluent invert, minimum 0.1 foot drop. Construct bends of the largest possible radius. Form channel sides and invert smooth and uniform, free of cracks, holes or protrusions.
(6) 
Do not permit pipe to project more than two inches into the manhole.
(7) 
Where special gaskets or water stops are recommended by pipe manufacturers for connections at manhole walls, these facilities shall be provided. All pipe connection joints shall be watertight.
(8) 
Seal joints between precast concrete manhole sections with preformed rubber gaskets or joint sealant compound.
(a) 
Place joint-sealant compound on lower section to be compressed by the weight of the upper section.
(b) 
Place rubber gasket in groove formed in spigot end. Equalize gasket tension.
(9) 
Step placement.
(a) 
Install manhole sections with steps in proper vertical alignment. Distance from top of rim to top step shall not be greater than 22 inches. Distance from floor of manhole to bottom step shall not be greater than 24 inches.
(b) 
Manhole steps shall be placed perpendicular to the mainline channel. Do not locate steps over channels.
(10) 
Install manhole frames and covers.
(a) 
In all streets and private roadways the top rim elevation of all manhole frames and covers shall be depressed 1/4 inch below the elevation of the adjacent street surface.
(b) 
Seal joint between manhole frame and manhole with joint-sealant compound.
(c) 
All manholes shall be adjusted to finished street grade utilizing no more than two two-inch thick concrete adjusting rings (four-inch maximum adjustment).
(d) 
If the proper adjustment cannot be achieved by the use of two rings, the cone section shall be removed and the proper barrel section inserted.
(e) 
All concrete adjusting rings shall be parged and plastered on the inside and outside with cement mortar 1/2 inch in thickness, carefully spread and thoroughly troweled to a smooth surface on the inside only.
(f) 
Install HDPE adjusting rings in accordance with manufacturer's recommendations using approved butyl sealant between cone and ring and between rings.
(11) 
New manholes constructed on existing pipelines.
(a) 
Only cast-in-place manhole bases shall be installed over existing sanitary sewers, unless prior approval is obtained from the Engineer.
(b) 
Carefully excavate around existing pipeline for placement of the new manhole base.
(c) 
Take all measures necessary to control flow through the existing pipeline and to prevent leakage into the new base.
(d) 
After completion of the manhole, carefully saw and remove the top portion of the existing pipeline.
(e) 
No materials, construction debris, or groundwater and surface water shall enter the existing pipelines.
(f) 
Upon completion of the connections, a properly sized plumber's stopper shall be placed in the new line and be adequately braced to prevent a blow-out.
(g) 
The stopper shall not be removed until written permission is granted by the municipality.
(12) 
Concrete wall penetration shall be cored at the sizes and locations indicated on the drawings or as recommended by the seal manufacturer. Place wall sleeves in the concrete walls in accordance with manufacturer's requirements.
F. 
Support of excavation: Article VII.
G. 
Control of excavated material: Article VII.
H. 
Dewatering: Article VII.
I. 
Shallow manholes. All manholes less than five feet in vertical height shall have a flat top section without a cone transition section and shall be constructed in accordance with Standard Detail DT 02601-4.[4]
[4]
Editor's Note: Said Standard Detail is included as an attachment to this chapter.
J. 
Backfilling.
(1) 
Backfill only after examination of the manhole by the municipality.
(2) 
Perform backfilling as specified in Article VII.
K. 
Disposal of excavated material: Article VII.
L. 
Restoration of surface areas.
(1) 
Restore paved areas as specified in Article XIII.
(2) 
Restore unpaved surfaces as specified in Article VII.