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Elements of a Good Concrete Pipe Specification. David JP Matocha Technical Resource Manager Hanson Pipe & Precast. A buried pipeline is a Structural System This structural system must consider both the Properties of the Pipe and the Properties of the Soil …. “READERS DIGEST Version”
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Elements of a Good Concrete Pipe Specification David JP Matocha Technical Resource ManagerHanson Pipe & Precast
A buried pipeline is a Structural System This structural system must consider both the Properties of the Pipe and the Properties of the Soil…
“READERS DIGEST Version” • Model “Outline” Specification (Handout) based upon AASHTO Section 27 – Concrete Pipe • 27.1 – General (Design) • 27.2 – Working Drawings • 27.3 – Materials • 27.4 – Assembly • 27.5 – Installation • 27.6 – Inspection • 27.7 – Measurement • 27.8 - Payment
Section 12 Bridge design… • Sets forth all LRFD (Load and Resistance Factor Design) design criteria for RCP • Allows Indirect Design and or Direct Design for RCP • Recommend using direct design for deep fills not listed in ACPA Fill Height Charts
Indirect Design • Calculate LRFD live load, dead load, fluid load • Takes soil/installation contribution into consideration • Calculate load on pipe in lbs/ dia (ft) / length(ft) • Determines strength class of pipe required (ASTM C-76) • Steel areas and concrete compressive strength set forth in AASHTO M 170/ASTM C-76
AASHTO Section 27 – 27.3 MATERIALS • Pipe Manufacturing Materials • Joint Materials
Joint Materials in 27.3 • Cement Mortar – soil tight • Other Joint Materials (Mastic) – soil or silt tight (horizontal) leak resistant (vertical) • Flexible watertight (Rubber Gasket) – silt tight or leak resistant
***AASHTO PP 63-09*** Pipe Joint Performance Parameters AASHTO Joint Selection Criteria = performance parameters divided into a hierarchy with 4 main sub-groups: • Special Design (Water Tight) • Leak Resistant • Silt Tight • Soil Tight
AASHTO Section 27 – 27.5Installation • 27.5 Installation – Contents….. • Bedding & Backfill Materials • Compaction Requirements • Type I – Type IV Standard Installations
$ $ $ $ $ $ Type 1 Installation High Quality Fill High Compaction Levels Inspection Lower Pipe Strengths
$ $ $ $ $ $ $ $ $ $ $ $ Type 4 Installation Native Soils Limited Compaction Required No Inspection High Pipe Strengths
AASHTO Section 27 – 27.6Field Inspection • 27.6 Inspection – Contents….. • Misalignment • Cracks • Spalls & Slabing