What is ASTM C478?

Table of Contents

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.

How thick are manhole walls?

b) Manholes 4 feet (1219 mm) in diameter shall have a bottom at least 6 inches (152 mm) thick and a wall at least 5 inches (127 mm) thick. c) Manholes 5 feet (1524 mm) in diameter shall have a bottom at least 8 inches (203 mm) thick and a wall at least 6 inches (152 mm) thick.

Are precast manholes reinforced?

Welded wire reinforcing or hoop steel is commonly used in precast concrete manholes. The minimum total wall reinforcing area required is 0.0025 times the internal diameter in inches per vertical foot as noted in ASTM C478.

What is ASTM C913?

ASTM C913-02. February 10, 2002. Standard Specification for Precast Concrete Water and Wastewater Structures. 1.1 This specification covers the recommended design requirements and manufacturing practices for monolithic or sectional precast concrete water and wastewater structures with the exception of…

What is the minimum depth of manhole?

(ii) Normal Manholes: Normal manholes (or medium manholes) are those which have depth more than 0.9 m and up to 2 m. These manholes may be of square or rectangular shape with minimum internal size 1 m x 1 m or 1.2 m x 0.9 m, or of circular shape with minimum internal diameter 0.9 m.

What is the minimum depth of an inspection chamber?

Small Inspection Chambers Small PPIC (polypropylene inspection chamber) up to 300mm diameter are generally only allowed to go to a depth of 600mm (0.6m) due to the narrow width of the chamber. These can be used in areas close to a house and near to the top of a drain.

Is code for precast manholes?

Cement used for the manufacture ofprecast concrete manhole covers shall conform to IS 269 or IS 455 or IS 1489(part 1) or IS 1489(Part 2)or IS6909or IS8041 orIS 8043 orIS 81120rlS 123300rIS 12269.

What is the diameter of manhole?

Precast 4-ft (48-in) diameter manholes are commonly used for both sanitary and stormwater access points. They accommodate sharp turns, integration of various pipes, pipe sizes, and elevation changes.

What is the minimum manhole diameter?

THE MINIMUM MANHOLE DIAMETER SHALL BE 48″ PER SB-53. 2. FOR SEWER MAINS GREATER THAN 42″ IN DIAMETER OR WITH A DEPTH THAT EXCEEDS 25 FEET IN DEPTH, SPECIAL DESIGN AND STRUCTURAL DETAILS FOR THE MANHOLE SHALL BE SHOWN ON THE PLANS.

What is the minimum depth for a manhole?

The minimum internal dimensions of a manhole are 600x900mm and they can be of any depth, although most modern manholes tend to be at least 1 metre deep with inspection chambers used for shallower depths.

How deep can a 300mm chamber be?

600mm
Small PPIC (polypropylene inspection chamber) up to 300mm diameter are generally only allowed to go to a depth of 600mm (0.6m) due to the narrow width of the chamber. These can be used in areas close to a house and near to the top of a drain.