Presentation on theme: "PIPE CONSTRUCTION Ohio Department of Transportation Corrugated Metal Pipe Installation Brian Flint Regional Engineer CONTECH CONSTRUCTION PRODUCTS, INC."— Presentation transcript:
PIPE CONSTRUCTION Ohio Department of Transportation Corrugated Metal Pipe Installation Brian Flint Regional Engineer CONTECH CONSTRUCTION PRODUCTS, INC.
What is There to Talk About ? Materials –Corrugations & Gauges –Coatings Structural Design Foundation Considerations Backfill Procedures Proper Cover Requirements CSP Joint Options
CONTECH Construction Products, Inc. 80 years of Metal Product Innovation
Corrugated Metal Pipe Design Criteria Hydraulics –Can You Achieve the Flow Requirements Structural Capacity –Can You Handle the Loading Condition Durability –Can You Last 75 Years –Prove It ! Economy
Structural Design 1.Determine the loads on the pipe. 2.Calculate ring compression. 3.Perform basic strength and stiffness checks. a)wall strength b)seam strength c)handling stiffness 4.Ensure minimum cover. 5.Check and account for corner pressures on multiple radius pipes. (i.e. pipe arches)
Physical Strength Structural Design Installation Stiffness –Importance of a Quality Backfill Deflection: Modified Iowa Formula Deflection = Load Pipe Stiffness + Soil Stiffness Soil Stiffness Accounts for 90% of Total Stiffness
Approved ODOT Sizes CONTECH size range from 6 to 144. ODOT Sizes: /4 or 1/2 deep deep Spiral Rib –ALUMINIZED Steel Type 2 Only and –Fiber Bonded CSP No Longer Available !
Durability How Long Should it Last ? 50 years or 75 years What is the Design Service Life Required ? ODOT has Durability Charts for Metal Pipe –L & D Manual: and ALT2 provides a minimum of 75 years for 16ga when As the gage is increased, the service life increases.
MANUFACTURER TYPE OF COATING GAUGE HEAT NUMBER DATE OF MANUFACTURE SPECIFICATIONS
Unloading and Handling Easily shipped in nested bundles (fewer trucks) Easy to handle and unload: –Light weight ( light equipment ) Lifting Lugs for Large Diameter –used with slings and hooks Slings or fork lift for smaller Diameter DO NOT Roll off truck –Long Joints ( 20 ft - 40 ft ) –Small outside Diameter
Proper Bedding Uniform Support –Lateral –Longitudinal Well graded granular material Free of frozen soil, sod, and large rocks Upper few inches should be relatively loose to allow corrugations to seat in bedding
Proper Foundation Firm Soft Pipe Uneven Foundation Pipe Uniform Foundation
Soft Foundations Soft In-Situ Soil W D Soft Shape Bottom For Pipe Arch For pipe-arch, excavate under pipe and replace with granular material only as deep as is necessary to obtain stable bed to install pipe Excavate Soft Soil and Replace with Highly compacted granular material
Minimum Permissible Spacing For Multiple Installations Arches Pipe Arches Span Pipe Diameter Span Up to 36…… to 108……1/3 span 108 to 189…..36 Diam. Up to 24… to 72….1/2 diam. 72 and over..36
Backfill Satisfactory material: –Well graded granular, w/ little to no plasticity –Clean/dense/stable/drainable soil Proper placement (6- 8 lifts on each side) Proper Compaction (90% Std. Density)AASHTO T99 Maintain minimum Height of Cover Installation conditions: –Embankment or Trench
Proper Backfill - Embankment 8 Lifts Thoroughly compact fill in 8 max loose lifts. Keep fill at same level on both sides of pipe. Diameter Lifts Should extend at least 1 pipe diameter on each side
Proper Backfill - Trench 8 Lifts Outside diameter plus sufficient room for compaction equipment Diameter
Tamping Under the Haunches Span Diameter Tampered Fill Care must be taken to assure that voids and soft spots are not left under the haunches of pipe
Proper Backfill: Pipe Arches Span Compacted Layers in 8 Lifts Compacted to max density below and beside the haunches Stable
Heavy Construction Loads Finished Grade Height of Cover Temporary Cover for Construction Loads Pipe
Compaction Techniques Walk Behind Compactor Sheep Foot or Rubber Tire Roller Vibrating Rollers Flooding with Water –approved ODOT methodology
Bands and Accessories HUGGER ® Band –Bolt Bar and Strap Connector –O Ring Gaskets Flat Band –Flat Gasket STAB Joint –Fluted Gasket Dimple Band
Easy to assemble Positive Joint, w/ pull apart resistance Soil tight Can be done with 1 or 2 people Small amount of tools –Felton Band Puller –Mallet –Open end or Deep socket wrench –Impact Equipment Your Greatest Strength Can be Your Greatest Weakness
Band Fasteners Scafco Angle –Used for smaller Diameter Pipe Bar, Bolt and Strap –Single –Double Rod and Lug (Levee Band Applications)
HUGGER Band 12-1/8 10-1/4 H-12 HUGGER BAND H-12 HUGGER BAND 12-1/8 10-1/4 O-Ring Gasket Gasketed Section Connection Detail Single Bolt, Bar, & Strap
HUGGER Bands Bands are normally furnished as follows: –12 thru 48 1 piece –54 thru 962 piece –102 thru piece Band fasteners are attached w/ spot welds Rerolled ends are 2-2/3 x 1/2 corrugation
Longer Lengths = Fewer Joints
In Line Fittings: Improved Hydraulics
O RING Gaskets: Soil Tight Joints
Band Puller: Helps You Get Started
Fabricated Fittings Full line of fittings including elbows, tees, wyes, risers, bulkheads, reducers, etc.
Conclusions Handle it Properly The Right Foundation: –The Key to a Quality Life Quality Backfill and Placement: –Important for all Systems –Roadway Embankment is Final Objective HUGGER Bands –Applied Properly –Stab Joints are Coming