ASTM C857-2019 pdf free download

ASTM C857-2019 pdf free download.Standard Practice for Minimum Structural Design Loading for Underground Precast Concrete Utility Structures
1. Scope
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, health, and environmental practices and deter- mine the applicability ofregulatory limitations prior to use. 1.4 This international standard was developed in accor- dance with internationally recognized principles on standard- ization established in the Decision on Principles for the Development of International Standards, Guides and Recom- mendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
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 lateral earth loads—the lateral pressure due to the effective weight of adjacent earth backfill. 3.1.3 lifting insert—device embedded or otherwise attached to the structure, designed and manufactured to support a measured, sustained, concentrated load. 3.1.4 live loads—will consist of any moving loads that can affect the design of the structure and their associated impact and surcharge loads. 3.1.5 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.4.1.4.3 When several distributed load areas overlap, the total load shall be considered as uniformly distributed over the area defined by the outside limits of the individual areas as indicated in Fig. 4. When the dimensions of the com-posite distributed load area exceeds the roof area only that portion of the distributed load on the roof area shall be considered in the design. 4.1.4.4 The distribution of wheel loads through earth fill are neglected when the depth of fill exceeds 8 ft (2.5 m). 4.2 Walls—The design loads for the walls ofany structure at or below ground level will consist of surcharge loads resulting from live loads, lateral earth loads that can develop as a result of earth pressure, hydrostatic pressure, and construction mate- rials such as used for roadways and walkways. Load diagrams of live load surcharge and lateral earth loads are shown in Fig. 5. 4.2.1 Live Loads: 4.2.1.1 When traffic can come within a horizontal distance from the structure equal to one half the height of the structure, a live load surcharge pressure of not less than 0.5 % of the wheel loading of the traffic involved shall be taken as the live load acting upon the wall of the structure.