Transcript Publish Bridge Inspections - Alberta Ministry of Transportation

Culverts
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What is a Culvert?
Culvert Components
Culvert Design and Construction
Culverts – Pros / Cons
Culverts
What is a Culvert?
Culverts
CHBDC
• Buried Structure
• Bridged Opening – 3m span
• Design – soil interaction
AT
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Surrounded by Soil
Below Road
Parallel to Stream
>= 1.5m DIA flow area
Culverts
Culvert Components
Culverts
Cover
Road
Inlet
Outlet
Rock
Barrel
Bevel End Clay Seal
Burial
(Embedment)
Crown
Invert
(Obvert)
Elevation View
Streambed
Culverts
Plan View
Culverts
Road
Cover
Rise
Burial
(Embedment)
Haunch
XS View
Span
Culverts
Culvert Shapes
Round
Ellipse
Arch
Box
Culverts
Culvert Shape in AT System
Arch
Ellipse
Box
Arch
Ellipse
Box
Round
All (~2820)
Arch
Arch
Box
Box
Round
Round
Ellipse
Ellipse
Round
> 1999 (~380)
Culverts
Culvert Materials
CSP
CIP
SPCSP
PC
WSP
Plastic
Culverts
Slide 11
Culverts
Culvert Material in AT System
WSP
Plastic
CIP PC
CIP
Precast
CSP
SPCSP
SPCSP
WSP
Plastic
CSP
Culverts
Culvert Size in AT System
100
90
80
Percent of Structures
70
60
50
40
30
20
10
0
1.5
2.5
3.5
4.5
5.5
Pipe Diameter (m)
6.5
7.5
8.5
Culverts
Culvert Age in AT System
100
90
80
Percent of Structures
70
60
50
40
30
20
10
0
1950
1960
1970
1980
1990
Year
2000
2010
2020
Culverts
Culvert Design and Construction
Culverts
Soil Steel Structures – No backfill
Culverts
Soil Steel Structures – Compacted backfill
Culverts
• Wide, Low Cover
• Acts like Bridge
• Costs like Bridge
Culverts
Pipe Arch
• High Stress
• Compaction??
• Low Resistance
• Bulging
Culverts
Culverts
Open
Bottom
Culverts
Culverts
Culverts
Base Preparation
Culverts
NO CAMBER
Culverts
Assembly – Side Plates
Culverts
Assembly – Roof Plates
Check Dimensions
Control Shape
Culverts
Backfill - Haunch
Culverts
Backfill - Sides
Culverts
Concrete End Treatment
Culverts
Culvert – Pros / Cons
Culverts
Cost
Culvert = $1000/m2 * pi * L * D
Bridge = $4000/m2 * L * W
Culvert
Bridge
Ratio
D
L
Cost
L
W
Cost
2
40
250,000
14
10
560,000
0.45
3
40
375,000
15
10
600,000
0.63
4
40
500,000
16
10
640,000
0.78
5
40
625,000
17
10
680,000
0.92
Culverts
Bridge Preferential Icing
Culverts
Bridge Barriers
Culverts
Unstable Valley Walls
Culverts
Need Soil Support
Culverts
Channel Work
Culverts
Blockage - Drift/Icing
Culverts
Pros
Cost
Cons
Need Soil Support
Preferential Icing
No Barriers
Unstable Valleys
Channel Work
Drift, Icing
Hydraulics, Fish Passage ????
Note: Selection of crossing structure is based on an optimization process
involving assessment of a range of options (see Bridge Conceptual
Design Guidelines)