ASTM International - ASTM C858-09
Standard Specification for Underground Precast Concrete Utility Structures
|Publication Date:||1 January 2009|
|ICS Code (Concrete and concrete products):||91.100.30|
1.1 This specification covers the recommended design criteria and manufacturing practices for monolithic or sectional precast concrete utility structures. Concrete pipe and box culverts are not covered under this specification. Also, precast concrete manholes covered in Specification C 478 are excluded from this specification.
1.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.
This specification covers the recommended design criteria and manufacturing practices for monolithic or sectional precast concrete utility structures. Forms shall be accurately constructed and... View More
This specification covers the recommended design criteria and manufacturing practices for monolithic or sectional precast concrete utility structures. Forms shall be accurately constructed and strong enough to maintain the structure's dimensions within the tolerances. Forms shall be cleaned before each use. The aggregates shall be sized, graded, proportioned, and thoroughly mixed in a batch mixer with proportions of cement and water as will produce a homogeneous concrete having the required specified compressive strength. Concrete shall be deposited as nearly as practicable in its final position. Structures shall be cured by an accepted industry method that will develop the required 28-day compressive strength without affecting the long-term durability of the concrete. The elastic method of structural design or the strength design method of reinforced concrete design, shall be used to design the concrete sections, including the reinforcement required, when the structure is subjected to the specified loading conditions. The structural design shall take into consideration the number, placement, and size of access openings. The minimum floor thickness resulting from slope shall be considered as the nominal floor thickness in the design of the structure. Duct terminators, knockouts, and sumps shall be designed to carry the loads imposed upon them. Compressive-strength