Oregon Dept. of Transportation Culvert Condition Assessment & Inventory Presented By: Paul R. Wirfs, P.E. Deputy Manger of Geo-Env Section Developed By: Robert E. Trevis, P.E. Culvert Engineering Program Lead

Outline Program Overview Challenges Culvert Handbook Data Collection Inventory Fields Condition Assessments Culvert Data – Making Sense of the data Drainage Facility Management System

Program Overview Oregon DOT’s Culvert Inventory and Condition Assessment: Culverts spans between 12 inches up to 20 feet on State Highways. 40 % of the State’s highway system completed. Equates to over 15,000 culverts Over 25% of these are in Poor or Critical condition. Benefits of completing a culvert inventory and condition assessment include: Reduced risk of sudden failure. Improved project prioritization of culvert projects. Reduced culvert infrastructure repair cost ( vs. emergency response) Anticipate about 35K to 40K total Unit been working on inventory/assessment for about 10 yrs Agency has recognized as official program in 2013

2016 Culvert Update Completed Inventory Routes on State highways only, including all priority routes as define by ODOT HMT

Challenges Safety High traffic volumes Accessibility High water levels Terrain Vegetation Clockwise: Photo 1: Scour at outlet. 25ft drop at outlet Photo 2: Inspector hiking back up 300 ft. plus embankment on Oregon Coast Photo3: Brusher making a tunnel into 15 ft. of blackberries.

Culvert Inspection & Inventory Handbook Developed to: Provide a quick reference guide for qualified employees who have successfully completed the core training requirements. Ensure repeatable results Provide program wide uniformity and consistency. Support a statewide program for inventory and determining the condition of culverts. Field handbook for our culvert inspectors Appropriate training is needed to utilize the field handbook Not meant as a training guide just a reference 1 week of in class training 1 week of field traning

Inventory Fields Inventory fields are only collected once on the initial site visit. Location Collected Inventory Information: Drainage Facility ID Bridge ID Number Stream Name Orientation Skew Inlet Side Facility Usage Height of Cover End Treatment Embankment Protection Material Span Rise Length Shape Material Facility Width Comment Field Screenshot of field application (ArchPad). Looking into better software and hardware. Currently using Trimble GeoXT Disadvantage is screen size & cost.

DFMS Condition Assessment

Condition Module * Condition Ratings Ratings are based on a scale from 1 to 4. Only use ‘0’ when unable to rate a particular condition rating. The ODOT “Culvert Inspection & Inventory Handbook ” lists the rating criteria text and photographs of each condition assessment field.

Condition Assessment Roadway: Hydraulics: Structure: Roadway Sag/ Guardrail Dip Embankment Popouts / Voids Pavement Cracks / Patches Hydraulics: Channel Alignment Embankment Protection Inlet Scour Inlet Embankment Protection Outlet Scour Outlet 3 groups of condition ratings Structure: General Barrel Condition Piping Damage Drift Invert Condition Settlement Vegetation Obstruction Out of Round Open Joints End Treatment Condition Cracking Strc Blockage

Roadway Assessment Embankment Pop Outs / Voids: Rate the roadway embankment slope for signs of failure and infiltration of fill into the culvert. Observations to Rate: Soil cracks along the contour of the slope Depressions and slumps Voids along the shoulder or embankment Example of rating field for the group: Roadway Assessment

Hydraulic Assessment Embankment Protection: Rate the condition of the embankment protection placed on the slope at the culvert inlet and outlet. Observations to Rate: Erosion around the culvert inlet and outlet of the roadway embankment Stability of embankment protection Loss of embankment protection Scour or undermining of embankment protection Example of rating field for the group: Hydraulic Assessment

Structure Assessment Cracking - Concrete: Rate circular concrete culverts and reinforced concrete boxes for any cracking. Observations to Rate: Cracking of concrete Spalling of concrete Exposed rebar. Also have separate Cracking rating pages for Metal and Plastic

Structure Assessment Cracking - Metal: Rate multi-plate culverts for cracking around the bolt holes and plate seams. Observations to Rate: Cracking at bolt holes Cracking along the plate seams Deterioration of the metal around the bolts or plate seams

Structure Assessment General Barrel Condition - Metal: Rate the general overall condition of the culvert. Observations to Rate: Corrosion of metal Cracking along bolt holes or plate seams Distortion or ‘Out of Round’ Holes or section loss of material Buckling of culvert material Infiltration of material Open or separated seams Also have separate General Barrel Condition rating pages for Metal and Plastic Important Note: General Barrel Condition rating must be equal to or lower than the lowest rating in the Structure section. ‘Drift’ ‘Vegetation’ and ‘End Treatment’ are not used in this determination.

Structure Assessment Invert Condition: Rate the condition of culvert invert and sides. Observations to Rate: Metal Severity of corrosion Holes in the invert or sides Section loss of material Concrete Spalls Abrasion Exposed Rebar Plastic Note the superscript for concrete. As this page is for both metal and concrete.

Structure Assessment Open Joints: Rate the separation of the connection between pipe sections and seams. Observations to Rate: Any separation between pipe sections Any separation of the seams between plates Voids in fill material visible through pipe separation Infiltration of backfill material

Structure Assessment Out of Round - Concrete: Rate the geometry of the cross sectional area of the culvert. Observations to Rate: Distortion of the culvert Flattening of the invert Flattening of the crown Also have separate Out of Round rating pages for Metal and Plastic

Making Sense of the Data

Making Sense of the Data Analytic Hierarchy Process (AHP) - Rational Decision Making Process Define hierarchy of criteria Calculate weighs for all criteria based on pairwise comparisons Evaluate results based on a performance score Culvert Score Roadway Embank Void/Popout Crack/Patch Roadway Sag Hydraulic End Treatment Embank Protect Outlet Embank Protect Inlet Scour Inlet Scour Outlet Structure (metal) Invert Cracking Out of Round Blockage Open Joints General Barrel Slide show the structure outline. Not all rating fields are used in the rating determinations. Other fields are used as Maintenance indicators.

Making Sense of the Data Analytic Hierarchy Process (AHP) - Rational Decision Making Process Pairwise comparison of ratings Slide shows the set up for the pair-wise comparisons of metal pipes. Column A: General Barrel Condition is being compared to other ratings fields in column B Column B: the rating fields being compared to General Barrel Condition Column A or B: Show which column has more importance Column (1-9): Scale of relative importance – General Barrel Condition has moderate importance over Invert 1 = Equal Importance. 9 = Extreme Importance.

Making Sense of the Data Analytic Hierarchy Process (AHP) - Rational Decision Making Process Calculate weights for criteria based on pairwise comparisons Normalized percentage for the weights based off previous slide.

Making Sense of the Data Calculate weights based on pairwise comparisons Weights Culvert Score Roadway 20% Embank Void/Popout 42.9% Crack/Patch 28.6% Roadway Sag 28.6% Hydraulic 12% End Treatment 18.9% Embank Protect Outlet 18.9% Embank Protect Inlet 20.6% Scour Inlet 12.1% Scour Outlet 29.6% Structure (metal)68% Invert 24.0% Cracking 3.9% Out of Round 6.1% Blockage 17.2% Open Joints 6.1% General Barrel 42.7% Final weights for subgroups, groups and overall culvert score.

Making Sense of the Data Pair-Wise Analysis - 3 different material categories Ratings and weights for the structure class will change based on one of the three material types. Concrete Metal Plastic Ratings and weights for the Hydraulic and Geotechnical classes always stay the same.

Making Sense of the Data Evaluate results based on a performance score Culvert Performance Score Culvert performance score is used to develop short and long term planning. Based on the score the culvert is zoned into four different categories. Good, Fair, Poor, and Critical. Uses the same scoring range for all three material categories. Integrated into Drainage Facility Management System Calibrated rating weights & performance score using about 400 to 500 inspection photographs Checked & refined calibration in field Performance Score Condition Meaning 3.61 – 4.00 Green Good 3.21 – 3.60 Yellow Fair 2.80 – 3.20 Orange Poor 0.00 – 2.79 Red Critical

Making Sense of the Data Example: DFMS Advanced Culvert Score   Rating Groups Rating Fields Rating Weight Sub Score Group Score Structure 68 % x 2.26 = 1.54 General Barrel Condition 2 .430 0.86 Invert Damage .240 0.48 Open Joints 3 .060 0.18 Out of Round 4 0.24 Blockage .170 0.34 Cracking .040 0.16 Rating Sub Score 2.26 Hydraulic 12 % x 2.58 = 0.31 Embankment Protection Inlet 0.68 Embankment Protection Outlet Scour Inlet .120 Scour Outlet .540 1.08 2.58 Roadway 20% x 3.46 = 0.69 Embankment Popouts / Voids 1.74 Pavement Cracks / Patches .285 Sag Roadway / Guardrail 3.46 Final Culvert Score 2.54 Metal Culverts: Example of culvert rating. Structure: Walk through the ratings multiplied by the weights to get sub score Sub score is multiplied by the Group weight to get group score of 1.54 Add up all three group score to get 2.54 From previous slide on performance score this culvert condition is critical.

Looking at DFMS Overall Rating screen of a culvert. Drainage Facility Management System: Web based database application develop by Oregon DOT Data stored in corporate Oracle tables Available to staff on ODOT’s intranet Track Information on culverts along the transportation system Stores inspections and photos to history section Enables ODOT to look at previous inspections and photographs

DFMS Condition Assessment Inspection Return Interval: Based on condition of the culvert using the performance scores. Good 20 years Fair 10 years Poor 2 years Critical 1 year

Culvert Assessment Information Oregon DOT Improved project prioritization and selection of culvert projects. Desk and project scoping for culvert repairs and replacement. Maintenance of culverts: Plugged with sediment Drift, Vegetation Scour

Culvert Inspector sense of humor Culvert Inspector sense of humor. Could not located outlet of culvert, but noticed seepage in the vicinity of the outlet.