1. Bridge Planning Why - Purpose Who - Bridge Planner
Where, When – AIT Roles
What – Constraints, Bridge Plan
How – Workflow, Tools

2. Why - Purpose Find Optimal Crossing Feasible Cost Effective Standards
Balance Issues
Feasible – function, safety, constructible, available technology, traffic interruption
Cost Effective – initial, life cycle, justified by benefits
Meet Standards – exceed where appropriate, justify exceptions
Balance Issues – many, multi-discipline, possibly conflicting
Find Optimal Crossing

3. Who - Bridge Planner Q = V * A K = L G2 – G1 Technical Scope Process
Planning
Design
Technical :
Expertise – hydrotechnical (river) and road geometrics
Familiarity with constraints from other disciplines
Ability to integrate technical components with additional constraints
Scope :
Mix planning (conceptual design) with RPW design
Evaluate array of solutions within broad context
Big picture solution – integrate many constraints (question, weigh, integrate, resolve conflicts)
Process :
Unique site constraints, natural sciences
Guidelines and principles (not code), few absolutes
Iteration and optimization – judgment, defence
Technical
Scope
Process

4. Where, When – AIT Roles Bridge Management Planning Studies Design
BEADS - integrate function and condition needs, user costs, holistic analysis on system level
Assessments – ID issues, replacement options, life cycle cost analysis
Planning Studies :
New corridors, realignments, twinning
ID likely design issues/constraints
crossing locations, feasible solutions, rough cost/configuration
Design :
Facilitate detailed design with bridge planning
Design and constraints/input for hwy encroachments, bridge repairs
Hydrotechnical review of impacts of other development on highway system – rivers, drainage
Inspection :
Specialized hydrographic survey, bank tracking analysis
Prioritize – susceptibility, post-flood
Design
Inspection

5. What – Constraints (core)
Hydrology
Hydraulics
River
Core constraints : Integral to bridge plan, iterative solution development
Hydrotechnical :
Hydrology – Q, HDG (channel capacity, historic HW, runoff potential)
Hydraulics – Y,V, local controls – structure sizing, u/s flooding
River – stable crossing, extent of RPW, channel realignment, skew, impact on others
Geometrics :
Alignment – curve radius, superelevation, spiral run-out, skew, land impact, travel length, safety
Gradeline – K,L, bridge height, freeboard, grade (1 – 3%), cut/fill balance, pavement transition
Bridge Geometrics – width, cross slope, sight distance, shy distance, gradeline, bridge geometrics, preferential icing, accesses (DB #8)
Gradeline
Bridge Geometrics
Alignment

6. What – Constraints (additional)
Structural
Environmental
Stakeholder
Additional Constraints : Important to consider, rely on expertise of others (question, weigh, modify, resolve conflict – integrate into overall plan)
Structural – span arrangements, structure depths, culvert vs. bridge
Geotechnical – slides, headslope ratios, pile depths, settlements, retaining walls
Environmental – fish passage, habitat compensation, wildlife passage, stormwater
Construction – detour/staging, flow constriction
Stakeholder – u/s flooding, flow alignment, travel distance, safety
Future Plans – widening, twinning, minimize throw-away, accommodate traffic
Construction
Future Plans
Geotechnical

7. What - Bridge Plan Gradeline Site Plan Elevation
Bridge Plan – components of DD drawings – documentation, review, but most importantly development
Site Plan :
Plan view – bridge plan superimposed on survey
shows x,y interaction of bridge fills with stream (also utilities, development)
Details fills, skew, RPW, r/w, road alignment
Elevation :
Cross section view along road centreline with sodlines
shows x,z interaction of bridge fills with stream
Details opening size, RPW, bridge grade
Gradeline :
Cross section with road gradeline superimposed on existing/natural ground
Shows vertical interaction of road with valley/terrain – cuts/fills
Details K,L, grades, accesses, HW
Other :
Horizontal Alignment – large scale plan view showing curve location and geometry, r/w, land impacts – often mosaic
Stream Profile – theoretical streambed, culvert inverts, not hydraulic slope
Bridge Section – document width, cross slope ; Site Map
Notes – survey, hydrotechnical (ice loads), road design standard, rock and geotextile quantities
Elevation

8. How – Workflow Site Inspection Hydrotech. Parameters Review Data
Review Available Data
File History - performance, HW Data, channel details, site specific issues
Design drawings, scour survey, reports, videos, photos
GIS - DA, basin, channel, site – DEM, airphotos, maps, streams
Other - WSC Data, AENV COP maps, floodplain study,…
Site Inspection :
Channel - Typical dimensions, features, controls, alignment, scour, erosion, HWM, drift, ice scars
Existing bridge – performance, impact, condition, safety, accesses
Site – local features, developments, utilities, access (survey, geotechnical, detour)
Hydrotechnical Parameters :
Hydrotechnical Design Guidelines (HDG) – Y,Q,V - Channel Capacity, Historic HW, Basin Runoff Potential
Confirm with U/S and D/S sites in reach
Geometric Parameters :
Existing Geometry - alignment, profile, cross slope (GPS pub, dwgs)
Design Standard - AADT, Classification, FPS
Horizontal – R, clear zone, Vertical – K sag and crest, max grade, Width – DB#8
Review Survey :
Completeness – all components (site plan, elevation, road profile, stream profile), extents, features (existing bridge, utilities)
Consistency – between views, with site observations, with DTM, airphoto
Other Constraints
Geotechnical – enough info for detailed design, headslope ratio match site, if >2:1 then options, foundation issues
Environmental - Fish Habitat Compensation/Passage – feasible, reasonable; Wildlife Passage – justify expense - resource impact, collisions
Other Constraints
Geometric Parameters
Survey

9. How – Workflow (cont.) Evaluate Develop Options Initial Option
Alignment - existing, offset (no detour), improvement
Gradeline - hydraulic (HW + freeboard + structure depth), standard (grade, K, cut/fill), match existing?
Fill Location - Match banks (minimal constriction), Skew – align with high flow path, rock (Y/N) – RPW?
Culvert - DIA = burial + Y + headloss, L = clear zone + sideslope + bevels, skew - align with channel, inverts – burial at ends
Develop Options :
Culvert - range of culvert sizes, shapes, types, tunnel
Bridge Fills - closer, further from channel – RPW, cost, hydraulics
Channel – realign (reduce skew), RPW options (spur, guidebank)
Span arrangement – pier location, gradeline (1 vs 3 span), 2:1 + geotech. remediation
Evaluate Options :
Costs - Structure + RPW + Road + Geotech + Traffic, life cycle
Pros/Cons – Road (safety, performance), Construction (risks, difficulty, staging), Environmental (impact, approvals)
Optimal – judgment, defence
Document Solution :
Purpose - facilitate detailed design, future assessment
Minimum - site plan, elevation, road profile - little extra effort for CAD drawings
Report – document parameters, constraints, and optimization process
Independent Review (+ Field Check) :
Accuracy, Consistency (standards, guidelines), Completeness (all feasible options) – not independent design
Verify optimal value – judgement
Post dwg. field check – final confirmation
Independent Review
Document

10. Tools Site Inspection Site Analysis Hydrotechnical Data Bridge Layout
Site Inspection Tools :
Video/Still Camera - Document fluvial processes, panoramic views
Handheld GPS - Locate features, track paths
Handheld Laser - Measure horizontal and vertical distances
Weighted Tape - Deck to water and streambed, handrail profile
Site Analysis (GIS):
Extract DA, profiles, channel parameters, assess basin terrain and stream network
Georeference airphotos – assess channel features, track historic changes
Import design option overlays, prepare maps for reports
Hydrotechnical Data :
HIS (Hydrotechnical Information System) - ID streams, bridges, data, stream profiles, file histories, summaries
Peakflow (WSC Data) - ID Gauges, annual flows, measurements, rating curves, hydrographs
Storm On Basin - ID all historic storms and rainfall on selected basin
Hydrotechnical Analysis :
Channel Capacity Calculator - Calculate Y,Q,V as per HDG, AIT open channel flow equation
Flow Constrict - Impact of bridge constriction – V, headloss
HydroCulv - Model complex hydraulic scenarios at culverts
HydroChan - Assess impact of gradually varied flow
Gradeline Analysis (BGrade):
Graphically align VPI’s to terrain, edit VPI, L
Report - K, detailed gradeline points, (EL, grade) at bridge fill ends
Plot - gradeline on terrain, bridge. multiple
Volume - Rough cut/fill based on terrain
Bridge Layout
Elevation – Calc and Plot bridge opening on XS data, interpolates gradeline data
Fills – Calc and Plot fill extent based on DEM data, georeferenced
RPW – Calc and Plot extent of headslope and RPW, calc rock volume, georeferenced
Bridge Layout
Hydrotechnical Analysis
Gradeline Analysis

11. Guidelines And Documents
Consultant Guidelines
Hydrotechnical Design Guidelines
Culvert Sizing Considerations
Bridge Size Culverts – Design Guidelines
Technical Documents :
Hydrology - Flood Context, Large Storms, Travel Time, Rainfall Runoff response
Hydraulics – OCF equations, practical modelling
BPG & DB :
BPG7 – spread footing
BPG9 – rock protection works
DB5 – retaining walls near rivers
Guidelines
Documents
BPG & DB