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Bridge Inspection Coding Guide

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Bridge Inspection Coding Guide Oregon Department of Transportation Bridge Inspection Coding Guide March 2015 Table of Contents How to use this Coding Guide .................................................................. 1 Responsibilities of the ODOT .................................................................... 2 Bridge Inspection Program ....................................................................... 2 Bridge Inspection Notes ........................................................................... 3 Bridge Inventory ....................................................................................... 4 General – Maintenance Expectations ...................................................... 8 Element Table ......................................................................................... 13 Defect Applicability Statements ............................................................. 18 ELEMENTS AND DEFECTS........................................................................ 22 Reinforced Concrete Elements ............................................................... 24 Concrete Crack Guideline ....................................................................... 27 Prestressed Concrete Crack Guideline: .................................................. 33 Steel Elements ........................................................................................ 35 Timber Elements ..................................................................................... 38 Timber Member Rating Guide ................................................................ 42 Bridge Bearings ....................................................................................... 64 Expansion Joint Elements ....................................................................... 66 Masonry Bridge Elements……………………………………………………………………70 Other Bridge Elements ........................................................................... 74 Tunnels ................................................................................................... 77 Miscellaneous Structures ....................................................................... 82 Miscellaneous Elements ......................................................................... 83 Approach Roadway and Embankment ................................................... 84 Bridge Paint Element .............................................................................. 86 Bridge Weathering Steel Element .......................................................... 87 Protective Systems ................................................................................. 88 Concrete Reinforcing Steel Protective Systems ..................................... 92 Concrete Protective Coating .................................................................. 92 Rating Elements ...................................................................................... 93 Quantities ............................................................................................... 93 Overlapping Defects ............................................................................... 94 Defect Hierarchy ..................................................................................... 96 NBI SECTION ......................................................................................... 101 NBI Item 36 ‐ Traffic Safety Features .................................................... 101 NBI Item 41 – Structure Status (Open, Posted, or Closed) ................... 107 New Bridge Posting Requirements for ‐ Specialized Hauling Vehicles 111 NBI Item 43 / 44 ‐ Main / Approach Span Type .................................... 116 NBI General Cond. Rating Table (NBI Items 58, 59, and 60): ............... 120 NBI Item 58 ‐ Deck Cond. Assessment Supplemental .......................... 121 Bridge Deck Commentary ..................................................................... 124 Sidewalk Inventory Rules: .................................................................... 126 Bridge Rail Commentary ....................................................................... 127 NBI Item 59 – Superstructure Condition Assessment Supplemental ... 129 Superstructure Commentary ................................................................ 134 NBI Item 60 ‐ Substructure Condition Assessment Supplemental ....... 138 Concrete Substructure Supplemental Rating Guideline ....................... 139 Timber Substructure Supplemental Rating Guideline .......................... 140 Steel Substructure Supplemental Rating Guideline ............................. 141 Substructure Commentary ................................................................... 142 Substructure Commentary/ Notes ....................................................... 144 NBI Item 61 ‐ Channel Protection Condition Assessment Rating Table and Supplemental................................................................................. 151 NBI 61 ‐ Channel and Channel Protection Assess Rating Description .. 152 Channel Assessment Commentary ....................................................... 155 NBI Item 62 ‐ Culvert Condition Assessment ........................................ 156 NBI Item 62 ‐ Culvert Condition Rating Guide ...................................... 157 Conc. Culvert Supplemental Rating Guide ........................................... 159 Culvert Definitions ................................................................................ 163 Culvert Commentary ............................................................................ 164 NBI Item 70 ‐ Bridge Posting ................................................................. 165 Non‐Load Rated Structures (Coding NBI Items 64 and 66) .................. 167 NBI Item 71 ‐ Waterway Adequacy ...................................................... 168 NBI Item 72 ‐ Approach Roadway Alignment ....................................... 170 NBI Item 103 ‐ Temporary Structure Designation ................................ 172 NBI Item 108 ‐ Wearing Surface / Protective System ........................... 173 NBI Item 113 ‐ Scour Code .................................................................... 175 Scour Monitoring Practice .................................................................... 179 Channel Commentary ........................................................................... 180 Channel Data Ownership ...................................................................... 180 Channel Definitions .............................................................................. 181 Business Rules ...................................................................................... 182 Concrete ............................................................................................... 183 Steel ...................................................................................................... 186 Timber .................................................................................................. 186 Masonry ................................................................................................ 187 Rails ....................................................................................................... 187 Abutments ............................................................................................ 188 New AASHTO Elements, definition of an abutment, ............................ 190 Oregon DOT .......................................................................................... 190 Column/Pile Definition ......................................................................... 195 Joints ..................................................................................................... 196 Element Specific ................................................................................... 196 Superstructure ...................................................................................... 197 Substructure ......................................................................................... 199 Calculating Defect Quantities ............................................................... 201 COMMENTARY (General Notes) ........................................................... 206 General – Inventory .............................................................................. 206 Bridge Inspection Reports .................................................................... 210 Deck Notes ............................................................................................ 212 Roadway Notes ..................................................................................... 212 Superstructure Notes ........................................................................... 213 Channel Notes ...................................................................................... 220 Bridge Inspection Frequency Guideline................................................ 221 Emergency Response Roles & Responsibilities .................................... 226 Concrete Structural Crack Inspection Frequency Guideline ................. 226 Scour Monitoring Frequency Decision Chart ....................................... 227 Bridge Deck Survey Guidelines ............................................................. 230 Inspection of Complex Structural Details (NBI Item 93) ....................... 231 Inspection of Steel Fatigue Sensitive Members ................................... 232 Timber Member Inspection Frequencies ............................................
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