Untitled - Future Pipe Industries

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3.4.2: Maximum cover height The maximum cover height depends on the type of installation, backfill material, its compaction, as well as native soil conditions. The figures below are for installation in good and stable native soils, and which provide adequate support for the pipes. Detailed selection tables, for each stiffness class, are shown in tables 5, 6, 7 and 8. Maximum Cover Depth for pipe installed in : Table 3 Stiffness Class (psi) SN 18 SN 36 SN 46 SN 72 Fully compacted gravel 46 ft 53 ft 54 ft 58 ft Full clean Sand compacted to 90% Std proctor 26 ft 43 ft 44 ft 48 ft Full mixed Sand compacted to 90% Std proctor 20 ft 25 ft 26 ft 30 ft Clean Sand compacted to 90% Std Proctor to 70 % of pipe ID N.R 16 ft 17 ft 23 ft Lightly tamped full clean sand** N.R 4ft 5ft 9ft 7
4.0: Backfilling and installation selection The installation type and choice of pipe bedding and backfill material is normally specified by the design Engineer, based on the specified pipe stiffness class (SN), maximum burial depth, vacuum requirements, and native soil conditions. 4.1: Acceptable pipe foundation, bedding and pipe zone backfill materials The following materials are generally acceptable for the pipe foundation, bedding and pipe zone backfill depending on the selected installation type. A) Crushed stones & rock B) Gravel C) Clean sand D) Mixed Sand E) Excavated granular material F) Cement stabilized sand (sand - cement mixture) ** Not recommended in high water table installations. A & B) Clean; single grade or well graded gravel and crushed rock/stones containing less than 15% sands and less than 5% fines, are an excellent backfill material. These materials are essentially self-compacting and the required density is generally achieved when dumped (maximum 12”lifts) with only light compaction required after the pipe haunches have been filled. In cases of high ground water table in the trench zone where the possibility of migration with native soils exist, a suitable geotextile filter membrane (e.g. Terram® ) should be used to line the trench bottom and sides up to the top of the pipe zone. If geotextile filter membrane is required, but unavailable, then clean sand should be used as the backfill material. (Unified soils classification: GW, crushed rock) Note: See section 4.3 on native soil migration C) Clean sand containing less than 5% fines, is good backfill material. Compacted to 90% standard proctor density, using hand tamping or plate vibrators (recommended). Maintain moisture content near optimum to minimize compaction effort. Place and compact in 12” maximum layers. (Unified soil classification per ASTM D2487: SW, SP) D) Mixed sand containing less than 12% fines is good backfill material. Compacted to 90% standard proctor density, using hand tamping or plate vibrators (recommended). Maintain moisture content near optimum to minimize compaction effort. Place and compact in 8” maximum layers. (Unified soil classification per ASTM D2487: SW, SP) E) Excavated granular material containing more than 12% fines consisting basically of gravel with fines or sand with fines. Compacted to 90 % standard proctor density, using hand tamping or plate vibrators (recommended). Maintain moisture content near optimum to minimize compaction effort. Place and compact in 6” maximum layer. (Unified soil classification per ASTM D2487: GM, GC, SM, SC) F) Cement stabilized sand is a mixture of one sack of cement per one ton of clean sand. This backfill material provides excellent support for pipe where native soil conditions are poor and would otherwise require a wide trench (up to 4 x DN) excavation, or a higher stiffness pipe. This mixture can be obtained dry, from ready-mix concrete suppliers. It should be placed in the foundation, bedding, haunches and pipe zone backfill in maximum 8” lifts. Each lift should be wetted with water and compacted with plate vibrators before the cement sets. 8
Page 2 and 3: All information was correct at the
Page 4 and 5: 1.0: Introduction This manual deals
Page 6 and 7: 2.5: Storing pipes on site 2.5.1 Di
Page 9: Figure 4: Pipes in the same trench
Page 13: 4.5: Classification of native soils
Page 16 and 17: Installation type I ASTM D1586 Blow
Page 18 and 19: Installation type I ASTM D1586 Blow
Page 20: Installation type I ASTM D1586 Blow
Page 23 and 24: 5.1.1: Joint lubricant For lubrican
Page 25: Mechanical lowering is used for lar
Page 28: 5.6: Pipes with locked joints For s
Page 31 and 32: Caution: Always provide a standard
Page 34 and 35: Figure 20 6.2: Pipe zone backfillin
Page 36 and 37: 6.3: Backfilling where temporary sh
Page 38 and 39: 7.0: Hydrostatic testing of pipelin
Page 40 and 41: 7.2: Bracing test-ends and set-up D
Page 42 and 43: 7.6: Final pressure test After all
Page 44 and 45: 7.9.2: Low head water test The Cont
Page 46 and 47: 9.0: Tapping water mains Pressure p
Page 48 and 49: APPENDIX II: Design considerations
Page 51 and 52: APPENDIX III AIR IN PIPELINES, AIR-
Page 53 and 54: APPENDIX IV FLANGE INSTALLATION INS
Page 55 and 56: Table 1a If connected to raised fac
Page 57 and 58: APPENDIX V: LIST OF REFERENCES The

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