ASTM C857-19 pdf download.Standard Practice for Minimum Structural Design Loading for Underground Precast Concrete Utility Structures.
1.1 This practice describes the minimum live loads and dead loads to be applied when designing monolithic or sectional precast concrete utility structures. Concrete pipe, box culverts, and material covered in Specification C478 are excluded from this practice. N OTE 1—For additional information see AASHTO Standard Specifica- tion for Highway Bridges, Seventeenth Edition. N OTE 2—The purchaser is cautioned that he must properly correlate the anticipated loading conditions and the field requirements with the design loads used.
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.
1.3 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 appro- priate safety and health practices and determine the applica- bility ofregulatory limitations prior to use. ”
2. Referenced Documents 2.1 ASTM Standards: 2 C478 Specification for Circular Precast Reinforced Concrete Manhole Sections
2.2 AASHTO Standard: Specification for Highway Bridges, Seventeenth Edition 3
3. Terminology 3.1 Definitions ofTerms Specific to This Standard:
3.1.1 dead loads—will consist of any other load that can affect the design of the structure.
3.1.2 lifting insert—device embedded or otherwise attached to the structure, designed and manufactured to support a measured, sustained, concentrated load.
3.1.3 live loads—will consist of any moving loads that can affect the design of the structure and their associated impact and surcharge loads.
3.1.4 utility structure—a structure that is used by electric, gas, communication, or similar industries. 4. Design Loads 4.1 Roof—The design loads for the roof of any structure at or below ground level consists of the live loads including impact and dead loads that can develop as a result of earth pressure, hydrostatic pressure, and construction materials such as used for roadways and walkways.
4.1.1 Live Loads—The vehicle and pedestrian load designa- tions are given in Table 1. Live load wheel spacing is shown in Fig. 1.
4.1.2 Impact:
4.1.2.1 The live loads A-16, A-12, and A-8 shall be in- creased as follows to sustain the effect of impact:
4.1.2.2 Live Load Increase: 0 to 12 in. (0 to 305 mm) below ground level, 30 % 13 to 24 in. (330 to 610 mm) below ground level, 20 % 25 to 35 in. (635 to 889 mm) below ground level, 10 % 36 in. (914 mm) or more below ground level, 0 %
4.1.3 Dead Loads—Dead loads will consist of the weight of the roof, roadbed, walkways, earth fill, access opening covers, and any other material that produces a static load.ASTM C857 pdf download.