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Structure Inspection Manual Part – Bridges Chapter – Substructure Table of Contents Substructure 2.4.1 Introduction 2.4.1.1 Abutments 2.4.1.2 Piers 2.4.1.3 Wingwalls 12 2.4.1.4 Integral Wingwall (Element 8400) 13 2.4.1.5 Foundation Types 14 2.4.2 Steel Substructure Elements 16 2.4.2.1 Steel Column (Element 202) 16 2.4.2.2 Steel Tower (Element 207) 18 2.4.2.3 Steel Abutment (Element 219) 19 2.4.2.4 Steel Pile (Element 225) 21 2.4.2.5 Steel Pier Cap (Element 231) 23 2.4.2.6 Fracture Critical Steel Substructures 27 2.4.3 Reinforced Concrete Substructure Elements 30 2.4.3.1 Reinforced Concrete Column (Element 205) 30 2.4.3.2 Reinforced Concrete Pier Wall (Element 210) 36 2.4.3.3 Reinforced Concrete Abutment (Element 215) 39 2.4.3.4 Reinforced Concrete Pile Cap/Footing (Element 220) 45 2.4.3.5 Reinforced Concrete Pile (Element 227) 47 2.4.3.6 Reinforced Concrete Cap (Element 234) 48 2.4.4 Prestressed Concrete Substructure Elements 53 2.4.4.1 Prestressed Concrete Column (Element 204) 53 2.4.4.2 Prestressed Concrete Pile (Element 226) 54 2.4.4.3 Prestressed Concrete Cap (Element 233) 55 2.4.5 Timber Substructure Elements 57 2.4.5.1 Timber Column (Element 206) 57 2.4.5.2 Timber Trestle (Element 208) 60 2.4.5.3 Timber Pier Wall (Element 212) 62 2.4.5.4 Timber Abutment (Element 216) 63 2.4.5.5 Timber Pile (Element 228) 66 2.4.5.6 Timber Pier Cap (Element 235) 70 2.4.6 Masonry Substructure Elements 75 August 2017 2-5-1 Structure Inspection Manual Part – Bridges Chapter – Substructure 2.4.6.1 Masonry Pier Wall (Element 213) 75 2.4.6.2 Masonry Abutment (Element 217) 77 2.4.7 Other Material Substructure Elements 82 2.4.7.1 Other Material Column (Element 203) 82 2.4.7.2 Other Material Pier Wall (Element 211) 83 2.4.7.3 Other Material Abutment (Element 218) 84 2.4.7.4 Other Material Pile (Element 229) 85 2.4.8 Substructure NBI Condition Ratings 88 August 2017 2-5-2 Structure Inspection Manual Part – Bridges Chapter – Substructure Table of Figures Figure 2.5.1.1-1: Typical Abutments Figure 2.5.1.1-2: Reinforced Concrete Sill Abutment Figure 2.5.1.2-1: Typical Piers Figure 2.5.1.2-2: Diagram showing differences between a Bent and Pier 11 Figure 2.5.1.2-3: Reinforced Concrete Columns and Pier Cap 11 Figure 2.5.1.2-4: Hammerhead Pier 12 Figure 2.5.1.2-5: Crash Wall 12 Figure 2.5.1.3-1: Reinforced Concrete Wingwall 13 Figure 2.5.2.2-1: Steel Towers/Trestles – Condition State 19 Figure 2.5.2.4-1: Heavy Corrosion at the Ground Line on Painted Steel Piles Condition State 22 Figure 2.5.2.5-1: Steel Box Pier Cap 23 Figure 2.5.2.7-1: Fracture Critical Riveted Steel Box Girder Pier Cap Note that the superstructure girders bear on the pier cap’s top flange by way of bearing devices 29 Figure 2.5.3.1-1: Reinforced Concrete Multi Column Piers 30 Figure 2.5.3.1-2: Hammerhead Pier Reinforced Concrete Column – Condition State (The cap of the hammerhead pier is reported under Element 234) 32 Figure 2.5.3.1-3: Concrete Column with Vertical Crack - Condition State 33 Figure 2.5.3.1-4: Transverse Flexural Cracks at the Base of a Column - Condition State 33 Figure 2.5.3.1-5: Column Spall with No Exposed Rebar - Condition State 34 Figure 2.5.3.1-6: Delaminated and Spalled Column - Condition State 34 Figure 2.5.3.1-7: Spalling on a Reinforced Concrete Shaft - Condition State 35 Figure 2.5.3.1-8: Heavily Spalled Column - Condition State 35 Figure 2.5.3.2-1: Reinforced Concrete Pier Wall 36 August 2017 2-5-3 Structure Inspection Manual Part – Bridges Chapter – Substructure Figure 2.5.3.2-2: Cracked, Delaminating and Spalled Reinforced Concrete Pier Wall – Condition State 38 Figure 2.5.3.2-3: Disintegration of a Reinforced Concrete Pier Wall – Condition State 39 Figure 2.5.3.3-1: Reinforced Concrete Semi Retaining Abutment 40 Figure 2.5.3.3-2: Sill Abutment and MSE Wall 41 Figure 2.5.3.3-3: Reinforced Concrete Abutment - Condition State 43 Figure 2.5.3.3-4: Vertical Crack in an Abutment – Condition State 44 Figure 2.5.3.3-5: Abutment Delaminations Under the Bearing – Condition State 44 Figure 2.5.3.3-6: Large Spall on Abutment Bearing Seat – Condition State 45 Figure 2.5.3.6-1: Reinforced Concrete Pier Cap 48 Figure 2.5.3.6-2: Reinforced Concrete Pier Cap - Condition State 51 Figure 2.5.3.6-3: Delamination on the Underside of a Pier Cap – Condition State 51 Figure 2.5.3.6-4: Delaminations on the Underside of a Pier Cap - Condition State 52 Figure 2.5.3.6-5: Pier Cap with Widespread Spalling – Condition State 52 Figure 2.5.4.4-1: Timber Abutment and Wingwalls 57 Figure 2.5.5.1-1: Timber Pier Columns 58 Figure 2.5.5.1-2: Timber Columns, Cap, and Cross-Bracing – Condition State 58 Figure 2.5.5.4-1: Timber Abutment, Pier Cap, and piles - Condition State 65 Figure 2.5.5.4-2: Bulging of a Timber Abutment (Settlement Defect) – Condition State 66 Figure 2.5.5.5-1: Timber Piling – Most in Condition State 67 Figure 2.5.5.5-2: Split and Decayed Timber Piling- Condition State 67 Figure 2.5.5.5-3: Split Timber Pile - Condition State 68 Figure 2.5.5.5-4: Timber Pile Decay at Ground Line – Condition State 68 Figure 2.5.5.6-1: Timber Pier Cap and Abutment - Condition State 73 August 2017 2-5-4 Structure Inspection Manual Part – Bridges Chapter – Substructure Figure 2.5.5.6-2: Split Pier Cap End (Note Plant Growth) - Condition State 73 Figure 2.5.5.6-3: Severe Insect Infestation Inside of a Pier Cap – Condition State 74 Figure 2.5.6.1-1: Masonry Tower (Pier) for a Suspension Bridge 75 Figure 2.5.6.2-1: Masonry Abutment 78 Figure 2.5.6.2-2: Masonry Abutment with Moderate Mortar Deterioration – Condition State 80 Figure 2.5.6.2-3: Masonry Abutment with Moderate Unit Deterioration – Condition State 80 Figure 2.5.6.2-4: Split and Spalled Masonry Units – Condition State 81 August 2017 2-5-5 Structure Inspection Manual Part – Bridges Chapter – Substructure 2.5 SUBSTRUCTURE 2.5.1 Introduction The bridge substructure includes all elements that support the superstructure Substructure elements deliver the superstructure reaction loads down to the foundation soil or bedrock In addition, substructures must also control deflections and settlements so as not to create serviceability problems for the riding surface or unintended overloads of the superstructure There are three main substructure components: abutments, piers, and wingwalls 2.5.1.1 Abutments Abutments function to support the ends of the bridge and to retain the soil fill under the approach Refer to Figure 2.5.1.1-1 for details of common abutment types Abutments must therefore resist vertical loads from the superstructure (live loads and superstructure selfweight), plus lateral loads due to soil pressure under the approach Lateral loads may also come from superstructure longitudinal forces due to temperature effects, vehicle braking forces, etc An abutment is designed to resist these longitudinal forces only if the bearings above are fixed Unintended superstructure longitudinal forces are delivered to the abutment when abutment expansion bearings have “frozen” due to corrosion or debris accumulation Figure 2.5.1.1-1: Typical Abutments To resist the loads described above, abutments must act as both compression and bending elements For shorter abutment heights (less than feet), bending due to lateral soil August 2017 2-5-6 Structure Inspection Manual Part – Bridges Chapter – Substructure pressure is not significant For taller abutment heights, the bending becomes a significant factor in the structure’s safe design Almost any type of material may be used to construct an abutment The most common is reinforced concrete, although masonry, timber, plain (un-reinforced) concrete, and (rarely) steel abutments have been built Current Wisconsin Department of Transportation (WisDOT) standards detail reinforced concrete and timber as materials to be used for typical highway crossings Abutment material type is defined by the material retaining the embankment To accurately fill out an inspection report, an inspector should know the correct terminology for the various abutment components These include: • Stem/breast wall: The stem, sometimes called breast wall, is the main body of the abutment It functions to deliver the superstructure reaction loads to the foundation and to retain much of the soil behind the abutment • Bearing/bridge seat: The bearing seat, sometimes called bridge seat, is the top surface of the stem/breast wall or cap upon which the bearing devices for the superstructure are placed • Backwall: Backwalls, located at the ends of the girders, retain the soil under the approach from spilling onto the bearing seat It may also provide support for concrete approaches and provide anchorage for expansion joint devices • Cheek wall: Cheek walls are features placed at either end of the abutment to protect the fascia bearings from the elements They also serve as architectural features to hide the bearings August 2017 2-5-7 Structure Inspection Manual Part – Bridges Chapter – Substructure Figure 2.5.1.1-2: Reinforced Concrete Sill Abutment 2.5.1.2 Piers Piers are intermediate support points for a bridge, used mainly for medium to long structures Piers must resist vertical loads from the superstructure (live loads and superstructure selfweight) and superstructure longitudinal forces due to temperature effects, vehicle braking forces, etc A pier is designed to resist these longitudinal forces only if the bearings above are fixed Unintended superstructure longitudinal forces are delivered to the pier when the pier expansion bearings have “frozen” due to corrosion or debris accumulation To resist the above loads, piers must act as both compression and bending elements Piers must also resist lateral forces transverse to the bridge centerline These forces come from wind pressures against the girders, centrifugal effects of traffic on curved bridges, stream flow, etc Most piers act as cantilever beams to resist loads longitudinal to the bridge centerline Depending on the configuration of its elements, piers act as frames, cantilevers beams or shear walls to resist loads transverse to the bridge centerline Refer to Figure 2.5.1.2-1 for details of common pier types August 2017 2-5-8 Structure Inspection Manual Part – Bridges Chapter – Substructure Figure 2.5.1.2-1: Typical Piers Almost any type of material may be used to construct a pier The most common is reinforced concrete, although masonry, timber, steel, and (rarely) plain concrete have been built Current WisDOT standards detail reinforced concrete as the material to be used for typical highway crossings To accurately fill out an inspection report, an inspector should know the correct terminology for the various pier components These include: • Pier cap: A pier cap is the horizontal component of a pier upon which the bearing devices for the superstructure are placed It also acts to tie the column tops together on multi-column piers to form a frame for resisting loads transverse to the bridge centerline When used on a multi-column pier, pier caps behave as bending members When used above pier walls, pier caps are simply an architectural feature formed by thickening the wall, although bending may come into play if the cap cantilevers over the ends of the wall Column: A column differs from a pile in the way that it is supported A column will be supported by a concrete pedestal or footing that can be beneath the ground level or exposed A pile will extend well past the ground level into more substantial bearing material, such as bedrock or stone that will provide the substructure with structural stability If a column’s pedestal or footing is buried it may be difficult to tell the difference between a column and a pile without looking at the bridge plans August 2017 2-5-9 Structure Inspection Manual Part – Bridges Chapter – Substructure • Solid wall: A solid pier wall is another component of a pier, many times the only component visible They are essentially very wide solid shafts of constant thickness that behave as shear walls They behave as beam/columns to resist axial compressive forces and bending longitudinal to the bridge centerline They are often used within streams or rivers because they offer less resistance to water flow than multicolumn piers For recording purposes, a vertical member may be considered a wall (versus a stem) when its height is less than its width • Web wall: Web walls are the concrete infill between the columns and pier caps of multicolumn piers Web wall thicknesses are always less than column widths They are used to change multicolumn pier lateral behavior from a frame to a shear wall, • Hammerhead: Hammerhead piers are comprised of a horizontal component (similar to a pier cap) of a pier upon which the bearing devices for the superstructure are placed However, the horizontal members are placed over a single vertical pier stem with a width much smaller than a pier wall Hammerheads caps are pure bending members that cantilever over either side of the stem • Stem: Stems are solid shaft vertical pier components that behave as a cantilever beam/column to resist axial compressive forces and bending longitudinal and transverse to the bridge centerline For recording purposes, a vertical member may be considered a stem or column (versus a wall) when its height exceeds its width • Crash wall: Crash walls are placed between the columns of multicolumn piers or between the stems of two individual piers supporting separate bridges Their purpose is to protect the pier base from rail car, ship or vehicle impacts Normally, the thickness of a crash wall is the same as the column/stem width to prevent snagging during a collision For recording purposes, when a crash wall is fully supported by a foundation (footing or piling) and the wall supports columns, the crash wall may be considered a pier wall If the crash wall is placed between the columns after-the-fact, the crash wall is considered secondary (it does not support the columns but rather braces) and shall not be considered a pier wall August 2017 2-5-10 Structure Inspection Manual Part – Bridges Chapter – Substructure • Checking the abutment for plumb visually or using a plumb bob • Noting any abrasion of the masonry for abutments located within a waterway • Examining the top surface (bearing seat) of the abutment for cracking and spalling Deterioration in these areas may be caused by frozen expansion bearings that transmit lateral forces to the pier not intended for in the original design • Checking to make sure weep holes in the abutment are functioning • Looking for vegetation growing inside of cracks or between the mortar and masonry unit Plant roots can exert prying forces that further deteriorate these materials • Checking to make sure surface drains are functioning properly and not allowing water to penetrate the approach fill behind the abutment • Hammer tapping random and suspect areas to evaluate the masonry’s soundness Element Defects Refer to Appendix A for defect descriptions The defects listed are unique to the element and element material (i.e concrete, steel, timber, etc.) The order of the defect numbering indicates the controlling defect Given multiple defects of the same condition state within a unit of measure, the lowest numbered defect controls Structural defects shall be coded in their entirety on the inspection report regardless if overlapping with material defects However, only the controlling defect will be counted in the total element condition state quantity Material Defects • Mortar Breakdown (1610) • Split/Spall/Patched Area (1620) • Masonry or Panel Displacement (1640) Structural Defects • Settlement (4000) • Scour (6000) Condition State Commentary Appendix A defines the Condition States for each individual defect The defects are expounded on and critical areas are discussed to aid the inspector in determining the severity of a defect The WisDOT Field Manual tabulates the element defects listed above and bases the Condition States on the progression of severity for each defect The Condition States are comprised of general descriptions and uniquely colored to follow the severity the description represents August 2017 2-5-79 Structure Inspection Manual Part – Bridges Chapter – Substructure • Condition State Good Green • Condition State Fair Yellow • Condition State Poor Orange • Condition State Severe Red Figure 2.5.6.2-2: Masonry Abutment with Moderate Mortar Deterioration – Condition State Figure 2.5.6.2-3: Masonry Abutment with Moderate Unit Deterioration – Condition State August 2017 2-5-80 Structure Inspection Manual Part – Bridges Chapter – Substructure Figure 2.5.6.2-4: Split and Spalled Masonry Units – Condition State August 2017 2-5-81 Structure Inspection Manual Part – Bridges Chapter – Substructure 2.5.7 Other Material Substructure Elements Other materials are intended to be used for members that are constructed of materials not otherwise defined 2.5.7.1 Other Material Column (Element 203) This element is for all other material columns regardless of protective system Element Level Inspection Other columns are recorded in units of “each” on the inspection report form Therefore, each element will be individually rated and assigned a Condition State It is the inspector’s task to examine each column and reasonably assign the most severe Condition State to the entire element This will quantify the element’s condition and help generate quantity/cost estimates for future remedial work Element Defects Refer to Appendix A for defect descriptions The defects listed are unique to the element and element material (i.e concrete, steel, timber, etc.) The order of the defect numbering indicates the controlling defect Given multiple defects of the same condition state within a unit of measure, the lowest numbered defect controls Structural defects shall be coded in their entirety on the inspection report regardless if overlapping with material defects However, only the controlling defect will be counted in the total element condition state quantity Material Defects • Corrosion (1000) • Cracking (1010) • Connection (1020) • Delamination/Spall/Patched Areas (1080) • Deterioration (1220) • Distortion (1900) Structural Defects • Settlement (4000) • Scour (6000) August 2017 2-5-82 Structure Inspection Manual Part – Bridges Chapter – Substructure Condition States Commentary Appendix A defines the Condition States for each individual defect The defects are expounded on and critical areas are discussed to aid the inspector in determining the severity of a defect The WisDOT Field Manual tabulates the element defects listed above and bases the Condition States on the progression of severity for each defect The Condition States are comprised of general descriptions and uniquely colored to follow the severity the description represents • Condition State Good Green • Condition State Fair Yellow • Condition State Poor Orange • Condition State Severe Red 2.5.7.2 Other Material Pier Wall (Element 211) This element defines those pier walls constructed of other materials This is for all pier walls regardless of protective systems Element Level Inspection On the inspection report form, other pier walls are recorded in units of lineal feet This measurement is taken as the length of the wall from end to end along the skew (if present) The total quantity is the sum of all pier wall lengths Where multiple condition states exist within a unit of measure only the predominant defect in severity and extent is recorded The other defects located within the unit of measure shall be captured by the inspector under the element or appropriate defect notes The sum of all of the reported condition states must equal the total quantity of the element This will quantify the element’s condition and help generate quantity/cost estimates for future remedial work Element Defects Refer to Appendix A for defect descriptions The defects listed are unique to the element and element material (i.e concrete, steel, timber, etc.) The order of the defect numbering indicates the controlling defect Given multiple defects of the same condition state within a unit of measure, the lowest numbered defect controls Structural defects shall be coded in their entirety on the inspection report regardless if overlapping with material defects However, only the controlling defect will be counted in the total element condition state quantity Material Defects • Corrosion (1000) • Cracking (1010) • Connection (1020) August 2017 2-5-83 Structure Inspection Manual Part – Bridges Chapter – Substructure • Delamination/Spall/Patched Areas (1080) • Deterioration (1220) • Distortion (1900) Structural Defects • Settlement (4000) • Scour (6000) Condition States Commentary Appendix A defines the Condition States for each individual defect The defects are expounded on and critical areas are discussed to aid the inspector in determining the severity of a defect The WisDOT Field Manual tabulates the element defects listed above and bases the Condition States on the progression of severity for each defect The Condition States are comprised of general descriptions and uniquely colored to follow the severity the description represents • Condition State Good Green • Condition State Fair Yellow • Condition State Poor Orange • Condition State Severe Red 2.5.7.3 Other Material Abutment (Element 218) This includes the sheet material retaining the embankment, and integral wingwalls and abutment extensions This is for all abutments regardless of protective systems Element Level Inspection On the inspection report form, other abutments are recorded in units of lineal feet This measurement is taken as the length of the abutment along the skew (if present) and the lengths of monolithic wingwalls The total quantity is the sum of all abutment and monolithic wingwall lengths Where multiple condition states exist within a unit of measure only the predominant defect in severity and extent is recorded The other defects located within the unit of measure shall be captured by the inspector under the element or appropriate defect notes The sum of all of the reported condition states must equal the total quantity of the element This will quantify the element’s condition and help generate quantity/cost estimates for future remedial work Element Defects Refer to Appendix A for defect descriptions The defects listed are unique to the element and element material (i.e concrete, steel, timber, etc.) The order of the defect numbering August 2017 2-5-84 Structure Inspection Manual Part – Bridges Chapter – Substructure indicates the controlling defect Given multiple defects of the same condition state within a unit of measure, the lowest numbered defect controls Structural defects shall be coded in their entirety on the inspection report regardless if overlapping with material defects However, only the controlling defect will be counted in the total element condition state quantity Material Defects • Corrosion (1000) • Cracking (1010) • Connection (1020) • Delamination/Spall/Patched Areas (1080) • Deterioration (1220) • Distortion (1900) Structural Defects • Settlement (4000) • Scour (6000) Condition State Commentary Appendix A defines the Condition States for each individual defect The defects are expounded on and critical areas are discussed to aid the inspector in determining the severity of a defect The WisDOT Field Manual tabulates the element defects listed above and bases the Condition States on the progression of severity for each defect The Condition States are comprised of general descriptions and uniquely colored to follow the severity the description represents • Condition State Good Green • Condition State Fair Yellow • Condition State Poor Orange • Condition State Severe Red 2.5.7.4 Other Material Pile (Element 229) This element defines other material piles that are visible for inspection Piles exposed from erosion or scour and piles visible during an underwater inspection are included in this element This element is for all other material piles regardless of protective system August 2017 2-5-85 Structure Inspection Manual Part – Bridges Chapter – Substructure Element Level Inspection Other piles are recorded in units of “each” on the inspection report form Therefore, each element will be individually rated and assigned a Condition State It is the inspector’s task to examine each pile and reasonably assign the most severe Condition State to the entire element This will quantify the element’s condition and help generate quantity/cost estimates for future remedial work Element Defects Refer to Appendix A for defect descriptions The defects listed are unique to the element and element material (i.e concrete, steel, timber, etc.) The order of the defect numbering indicates the controlling defect Given multiple defects of the same condition state within a unit of measure, the lowest numbered defect controls Structural defects shall be coded in their entirety on the inspection report regardless if overlapping with material defects However, only the controlling defect will be counted in the total element condition state quantity Material Defects • Corrosion (1000) • Cracking (1010) • Connection (1020) • Delamination/Spall/Patched Areas (1080) • Deterioration (1220) • Distortion (1900) Structural Defects • Settlement (4000) • Scour (6000) Condition States Commentary Appendix A defines the Condition States for each individual defect The defects are expounded on and critical areas are discussed to aid the inspector in determining the severity of a defect The WisDOT Field Manual tabulates the element defects listed above and bases the Condition States on the progression of severity for each defect The Condition States are comprised of general descriptions and uniquely colored to follow the severity the description represents • Condition State Good Green • Condition State Fair Yellow August 2017 2-5-86 Structure Inspection Manual Part – Bridges Chapter – Substructure • Condition State Poor Orange • Condition State Severe Red August 2017 2-5-87 Structure Inspection Manual Part – Bridges Chapter – Substructure 2.5.8 Substructure NBI Condition Ratings Part of every Routine Inspection is rating the substructure according to the Federal Highway Administration (FHWA) General Condition Rating Guidelines The numeric condition ratings of these guidelines describe existing bridge components as compared to their as-built condition Ratings range from to 0, with describing components in excellent condition and describing failed components Because only a single number is used to rate the substructure, the rating must characterize its overall general condition The rating should not be used to describe local areas of deterioration, such as isolated heavy spalling However, widespread heavy spalling would certainly influence the rating A proper rating will therefore consider the severity of deterioration plus the extent to which it is distributed throughout the substructure National Bridge Inventory (NBI) ratings are used to evaluate the state of deterioration of the substructure material Since material condition is independent of a bridge’s load-carrying capacity, postings or original design capacities less than current legal loads will not influence the rating Similarly, temporary substructure support does not change or improve the condition of the substructure material Therefore, temporary strengthening methods will not influence the substructure rating The NBI general condition ratings found in the FHWA guidelines apply to decks, superstructures, and substructures Ratings to apply to components built of any material, while ratings to mention specific defects or deterioration that can be applied to certain materials Because the NBI general condition ratings apply to a wide range of components and materials, Wisconsin has developed supplemental rating guidelines These supplemental rating guidelines are used to assist the inspector in properly assigning condition ratings to specific components constructed of the most commonly used materials The general condition ratings, along with the Wisconsin supplemental rating guidelines for substructures, are as follows: Code (Rating) N Description NOT APPLICABLE Wisconsin Supplemental Rating Guidelines: Used only for culverts and spandrel arches where footings cannot be seen EXCELLENT CONDITION Wisconsin Supplemental Rating Guidelines: There are no noticeable or noteworthy deficiencies that affect the condition of the substructure There may be insignificant scrape marks caused by drift or collision August 2017 2-5-88 Structure Inspection Manual Part – Bridges Chapter – Substructure VERY GOOD CONDITION – no problems noted Wisconsin Supplemental Rating Guidelines: Concrete Substructure – there may be shrinkage cracks, light scaling or insignificant spalling which does not expose reinforcing steel There may be insignificant damage caused by drift or collision with no resulting misalignment Corrective action is not required Steel Substructure – there may be insignificant damage caused by drift or collision with no resulting misalignment Corrective action is not required Timber Substructure – there may be insignificant damage caused by drift or collision with no resulting misalignment Corrective action is not required Masonry Substructure – there may be insignificant spalling of the masonry units Damage caused by drift or collision may have occurred, but with no resulting misalignment Corrective action is not required GOOD CONDITION – some minor problems Wisconsin Supplemental Rating Guidelines: Concrete Substructure – there may be minor cracking with possible leaching or spalls with no detrimental effect on bearing area Leakage of expansion devices may have caused minor cracking to start Minor scouring may have occurred Steel Substructure – leakage of expansion devices may have started minor rusting without measurable section loss Minor scouring may have occurred Timber Substructure – insignificant decay, cracking or splitting Minor scouring may have occurred Masonry Substructure – there may be minor cracking or the mortar or spalls/cracking of the masonry units with no detrimental effect on bearing area Minor scouring may have occurred SATISFACTORY CONDITION – structural elements show some minor deterioration Wisconsin Supplemental Rating Guidelines: Concrete Substructure – minor deterioration or disintegration, spalls, cracking or leaching with little or no loss of bearing area Shallow, local scouring may have occurred near the foundation August 2017 2-5-89 Structure Inspection Manual Part – Bridges Chapter – Substructure Steel Substructure – corrosion, but no measurable section loss Shallow, local scouring may have occurred near the foundation Timber Substructure – some initial decay, cracking or splitting Fire damage is limited to surface scorching with no measurable section loss Masonry Substructure – minor deterioration or disintegration, spalls or cracking of the masonry units or mortar with little or no loss of bearing area Shallow, local scouring may have occurred near the foundation FAIR CONDITION – all primary structural elements are sound but may have minor section loss, cracking, spalling or scour Wisconsin Supplemental Rating Guidelines: Concrete Substructure – measurable but minor section loss may exist, with possible exposed reinforcing steel Scour may be progressive and/or is becoming more prominent with possible top of footing exposure However, no misalignment or settlement is noted Steel Substructure – corrosion with measurable but minor section loss Scour may be progressive and/or is becoming more prominent with possible top of footing exposure However, no misalignment or settlement is noted Timber Substructure – moderate decay, cracking or splitting A few secondary members may need replacement Fire damage is limited to surface charring with minor, measurable section loss There may be some exposure of piles as a result of erosion, reducing penetration Masonry Substructure – minor deterioration or disintegration, spalls or cracking of the masonry units and mortar with little or no loss of bearing area Scour may be progressive and/or is becoming more prominent with possible top of footing exposure However, no misalignment or settlement is noted POOR CONDITION – advanced section loss, deterioration, spalling or scour Wisconsin Supplemental Rating Guidelines: Concrete Substructure – structural cracks and advanced deterioration Additional backfilling is required Extensive scouring or undermining of the footing is affecting the stability of the unit and requiring corrective action August 2017 2-5-90 Structure Inspection Manual Part – Bridges Chapter – Substructure Steel Substructure – corrosion with extensive section loss Additional cross bracing is required Extensive scouring or undermining of the footing is affecting the stability of the unit and requiring corrective action Timber Substructure – substantial decay, cracking, splitting or crushing of primary members, requiring replacement Fire damage with significant section loss that may reduce the load-carrying capacity of the member Extensive exposure of piles as a result of erosion, thus reducing penetration and affecting the stability of the unit Masonry Substructure – structural cracks and advanced deterioration of the masonry units and mortar Additional backfilling is required Extensive scouring or undermining of the footing is affecting the stability of the unit and requiring corrective action SERIOUS CONDITION – loss of section, deterioration, spalling or scour have seriously affected primary structural components Local failures are possible Fatigue cracks in steel or shear cracks in concrete may be present Wisconsin Supplemental Rating Guidelines: Concrete Substructure – severe disintegration Reinforcing steel is exposed with advanced stages of corrosion There is severe section loss in critical stress areas Bearing areas are seriously deteriorated with considerable loss of bearing Severe scouring or undermining of the footings affects the stability of the unit Settlement may have occurred Shoring is considered necessary (not just precautionary) to maintain the safety and alignment of the structure Steel Substructure – there is severe section loss in critical stress areas Bearing areas are seriously deteriorated with considerable loss of bearing Severe scouring or undermining of the footings affects the stability of the unit Settlement may have occurred Shoring is considered necessary (not just precautionary) to maintain the safety and alignment of the structure Timber Substructure – there is severe section loss in critical stress areas Major fire damage is present that will substantially reduce the load-carrying capacity of the member Bearing areas are seriously deteriorated with considerable loss of bearing Settlement may have occurred Shoring is considered necessary (not just precautionary) to maintain the safety and alignment of the structure Masonry Substructure – severe disintegration of the masonry units and mortar There is severe section loss in critical stress areas Bearing areas are seriously deteriorated with considerable loss of bearing Severe scouring or undermining of the footings affect the stability of the unit Settlement may have occurred Shoring is considered necessary (not just precautionary) to maintain the safety and alignment of the structure August 2017 2-5-91 Structure Inspection Manual Part – Bridges Chapter – Substructure CRITICAL CONDITION – advanced deterioration of primary structural elements Fatigue cracks in steel or shear cracks in concrete may be present or scour may have removed substructure support Unless closely monitored it may be necessary to close the bridge until corrective action is taken Wisconsin Supplemental Rating Guidelines: Concrete Substructure – concrete cap is soft and spalling with reinforcing steel exposed with no bond to concrete The top of the cap is split or a column has undergone a shear failure Scouring is sufficient that the substructure is near a state of collapse Piers have settled Steel Substructure – members have critical section loss Holes in the web and/or knife-edged flanges are typical Scouring is sufficient that the substructure is near a state of collapse Piers have settled Timber Substructure – the primary members are crushed or split and ineffective Piers have settled Masonry Substructure – scouring is sufficient that the substructure is near a state of collapse Piers have settled “IMMINENT” FAILURE CONDITION – major deterioration or section loss present in critical structural components or obvious vertical or horizontal movement affecting structural stability Bridge is closed to traffic but corrective action may put it back in light service Wisconsin Supplemental Rating Guidelines: Bridge is closed Corrective action may put it back in light service FAILED CONDITION – out of service, beyond corrective action Wisconsin Supplemental Rating Guidelines: Bridge is closed Replacement is necessary One suggested method for establishing a substructure rating is to identify phrases within the general condition/Wisconsin supplemental guideline language that describe a substructure condition more severe than what actually exists The correct rating number will be one number higher than the one describing the more severe condition For example, suppose a reinforced concrete substructure has extensive delaminations, plus spalling with exposed reinforcing steel The spalls occur on the tension side of the caps and August 2017 2-5-92 Structure Inspection Manual Part – Bridges Chapter – Substructure on random sides of the columns, but section loss of the reinforcing steel is minimal Condition rating indicates that there is advanced deterioration and spalling Condition rating indicates that deterioration and spalling have seriously affected the primary structural components, and that the reinforcing steel is in the advanced stages of corrosion Using the method described above, Condition rating describes a situation more severe than what actually exists on the substructure Therefore, a rating of would be appropriate Another method to help narrow down the substructure rating number is to group the numbers in more general categories Ratings of to apply to substructures in good condition, to suggest fair condition, to suggest poor condition, suggests poor/critical condition, and to suggest critical condition It is also important to note that there is a significant change from a substructure in condition rating (minor section loss, structural elements sound) to condition rating (advanced section loss, advanced deterioration) A reduction in loadcarrying capacity can be measured/calculated when a substructure enters condition rating August 2017 2-5-93 ... Material Defects • Corrosion (1 000) • Cracking (1 010) • Connection (1 020) • Distortion (1 900) Structural Defects • Settlement (4 000) • Scour (6 000) • Microbial Induced Corrosion (8 901) Condition State... Material Defects • Corrosion (1 000) • Cracking (1 010) • Connection (1 020) • Distortion (1 900) Settlement Defects • Settlement (4 000) • Scour (6 000) • Microbial Induced Corrosion (8 901) Condition State... Material Defects • Corrosion (1 000) • Cracking (1 010) • Connection (1 020) • Distortion (1 900) Structural Defects • Settlement (4 000) • Scour (6 000) • Microbial Induced Corrosion (8 901) Condition State