ASTM C923/C923M-20

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: C923 − 18 C923/C923M − 20
Standard Specification for
Resilient Connectors Between Reinforced Concrete Manhole
Structures, Pipes, and Laterals
This standard is issued under the fixed designation C923;C923/C923M; the number immediately following the designation indicates the
year of original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last
reapproval. A superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
This standard has been approved for use by agencies of the U.S. Department of Defense.
1. Scope
1.1 This specification covers the minimum performance and material requirements for resilient connectors used for connections
between reinforced concrete manholes conforming to Specification C478C478/C478M and pipes, between wastewater structures
and pipes, and between precast reinforced concrete pipe and laterals.
1.1.1 These connectors are designed to minimize leakage between the pipe and manhole, and between the pipe and lateral.
1.2 A complete metric companion to SpecificationThe values stated in inch pound C923 has been developed—or SI units
areC923M; therefore, no metric equivalents are presented in this specification. to be regarded separately as standard. The SI units
NOTE 1—This specification covers the design, material, and performance of the resilient connection only. Connections covered by this specification are
adequate for hydrostatic pressures up to 13 psi (30 ft) without leakage when tested in accordance with Section 7. Infiltration or exfiltration quantities for
an installed system are dependent upon many factors other than the connections between manhole structures and pipe, and allowable quantities must be
covered by other specifications and suitable testing of the installed pipeline and system.are shown in brackets. The values stated in each system
may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two
systems may result in nonconformance with the standard.
NOTE 1—This specification covers the design, material, and performance of the resilient connection only. Connections covered by this specification are
adequate for hydrostatic pressures up to 13 psi (30 ft) [90 kPa (9.1 m)] without leakage when tested in accordance with Section 7. Infiltration or exfiltration
quantities for an installed system are dependent upon many factors other than the connections between manhole structures and pipe, and allowable
quantities must be covered by other specifications and suitable testing of the installed pipeline and system.
1.3 The following precautionary caveat pertains only to the test methods portion, Section 7, of this specification: This standard
does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this
standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory
limitations prior to use. For a specific precaution statement, see 7.2.5.
1.4 This international standard was developed in accordance with internationally recognized principles on standardization
established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued
by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
2. Referenced Documents
2.1 ASTM Standards:
This specification is under the jurisdiction of ASTM Committee C13 on Concrete Pipe and is the direct responsibility of Subcommittee C13.06 on Manholes and Specials.
Current edition approved Sept. 1, 2018Sept. 1, 2020. Published October 2018September 2020. Originally approved in 1979. Last previous edition approved in 20132018
ɛ1
as C923 – 08C923 – 18.(2013) . DOI: 10.1520/C0923-18.10.1520/C0923_C0923M-20.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
C923/C923M − 20
A493 Specification for Stainless Steel Wire and Wire Rods for Cold Heading and Cold Forging
A666 Specification for Annealed or Cold-Worked Austenitic Stainless Steel Sheet, Strip, Plate, and Flat Bar
C478C478/C478M Specification for Circular Precast Reinforced Concrete Manhole Sections (Metric) C0478_C0478M
C822 Terminology Relating to Concrete Pipe and Related Products
C913 Specification for Precast Concrete Water and Wastewater Structures
D395 Test Methods for Rubber Property—Compression Set
D412 Test Methods for Vulcanized Rubber and Thermoplastic Elastomers—Tension
D471 Test Method for Rubber Property—Effect of Liquids
D543 Practices for Evaluating the Resistance of Plastics to Chemical Reagents
D573 Test Method for Rubber—Deterioration in an Air Oven
D624 Test Method for Tear Strength of Conventional Vulcanized Rubber and Thermoplastic Elastomers
D883 Terminology Relating to Plastics
D1149 Test Methods for Rubber Deterioration—Cracking in an Ozone Controlled Environment
D1566 Terminology Relating to Rubber
D2137 Test Methods for Rubber Property—Brittleness Point of Flexible Polymers and Coated Fabrics
D2240 Test Method for Rubber Property—Durometer Hardness
NOTE 2—For more information about wastewater structures, see Specification C913.
3. Terminology
3.1 Definitions:
3.1.1 Terms relating to plastics and rubber shall be as defined in Terminologies D883 and D1566, respectively.
3.1.2 Terms relating to precast concrete pipe, manholes, and related products shall be as defined in Terminology C822 and as
modified in 3.1.3 – 3.1.6.
3.1.3 connector—connector, n—the entire assembly including resilient seals and metallic or nonmetallic mechanical devices, if
any, used therein.
3.1.4 lateral—lateral, n—the small diameter pipe connected to the main line pipe.
3.1.5 pipe—pipe, n—the inlet or outlet pipe connected to the manhole.
3.1.6 pipe stub—stub, n—a short section of pipe, installed in the structure as an inlet or outlet pipe, for future connection.
4. Materials and Manufacture
4.1 All materials shall conform to the following requirements:
4.1.1 Resilient materials for connectors and filler rings shall be manufactured from natural or synthetic rubber and shall conform
to the requirements prescribed in Table 1. If a splice is used in the manufacture of the seal, its strength shall be such that the seal
shall withstand a 180° bend with no visible separation.
4.2 Mechanical Devices—Expansion rings, tension bands, and take-up devices used for mechanically compressing the resilient
portion of the connector against the pipe, manhole or wastewater structure; shall be made from a material or materials in
combination that will ensure durability, strength, resistance to corrosion, and have properties that will ensure continued resistance
to leakage. All metallic mechanical devices, including castings and bolt assemblies used to mechanically deform resilient materials
shall be constructed of corrosion resistant materials meeting the physical properties and chemical composition requirements of
Specifications A493 and A666, Type 302 through Type 316.
NOTE 3—Experience has shown that successful performance of this product depends on the type of bedding and backfill and the care in the field
installation of the manhole or wastewater structure and connecting pipes. The owner is cautioned to require inspection at the construction site.
5. Principles of Design
5.1 The design of the connector shall be such that positive seal is accomplished at two locations: (1) between the connector and
C923/C923M − 20
TABLE 1 Resilient Material Tests
A
Test Test Requirements ASTM Test Method
Chemical resistance: D543, at 22°C for 48 h
Chemical resistance: D543, at 71.6°F [22°C] for 48 h
1 N sulfuric acid no weight loss
1 N hydrochloric acid no weight loss
Tensile strength 1200 psi, min D412
Tensile strength 1200 psi [8.3 MPa], min D412
Elongation at break 350 %, min
B
Hardness ±5 from the connector manufacturer’s specified hard- D2240 (Shore A durometer)
ness
Accelerated oven-aging decrease of 15 %, max, of original tensile strength, D573, 70 ± 1°C for 7 days
decrease of 20 %, max, of elongation
Accelerated oven-aging decrease of 15 %, max, of original tensile strength, D573, 158 ± 1.8°F [7
...