What is ASTM C913?

ASTM C913 – 21 Standard Specification for Precast Concrete Water and Wastewater Structures.

What is a precast concrete manhole?

Precast sanitary manholes provide both access and transition points for your sanitary sewer system. Typical configurations consist of a base unit, risers and a top section. Available in sizes from 48” to 144” diameter. Precast Inverts Available. Standard Cones and Custom Tops Available.

What is ASTM 858?

ASTM-C858 › Standard Specification for Underground Precast Concrete Utility Structures. This specification covers the recommended design criteria and manufacturing practices for monolithic or sectional precast concrete utility structures.

How are manholes measured?

1) For design purposes, the manhole depth is measured from the top of the manhole frame and cover (rim) to the invert of the manhole (the invert of the channel at the center of the manhole). 2) Design all new manholes as precast concrete manholes. b. Precast Concrete Manholes.

Are manholes reinforced?

Standard manhole flanged bases comprise circular slabs with minimum thicknesses shown in the table below. The flange projects 150mm from the outer diameter of the manhole riser to provide resistance to floatation. These reinforced base slabs are factory cast into a manhole riser of any specified standard length.

Why are manhole covers round?

But why are manhole covers round? Because there are no angles for alignment, the round shape makes these heavy covers easier to put back on once they’re taken off. Round covers are also easier to manufacture. But the main reason manhole covers are round is so they won’t accidentally fall into the manhole itself.

How wide is manhole?

Precast 4-ft (48-in) diameter manholes are commonly used for both sanitary and stormwater access points.

How long does it take to construct a manhole?

It may take as much as 10 days to install a manhole and restore the surface to meet existing conditions. It will be necessary to install a sewer by-pass throughout the duration of sewer replacement activities. A manhole may be abandoned in place when it is no longer needed.

What is ASTM c478?

The ASTM C478 standard contains the requirements for the manufacture and purchase requirements of products used for the assembly and construction of circular, vertical precast concrete manholes and structures. The scope of C478 includes structures used in precast sewer, drainage and water works.

What is the scope of c478?

The scope of C478 includes structures used in precast sewer, drainage and water works. ASTM C478 is an important standard under the jurisdiction of ASTM C13, the technical committee on concrete pipe, established in 1931.

What are the ASTM c877 external sealing bands?

ASTM C877, “Standard Specification for External Sealing Bands for Concrete Pipe, Manholes and Precast Box Sections” ASTM C877 covers three different types of external sealing bands: • Type I: Rubber and Mastic Bands.

What does c478m-20 stand for?

ASTM C478 / C478M-20, Standard Specification for Circular Precast Reinforced Concrete Manhole Sections, ASTM International, West Conshohocken, PA, 2020, www.astm.org