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From page 26... ... This part of the field manual will discuss the specific PDA procedures and considerations for bridges, tunnels, walls, culverts, and overhead signs. Each chapter provides a general overview of the highway structure, a schematic, the PDA procedure, a list of elements, and the damage states to define minor, moderate, and severe damage levels for each element. Read the entire page →
From page 27... ... Part II: PDA of Highway Structures 29 Bridges Bridges are the most common and complex type of highway structures in the United States. They are built with the purpose of providing passage over or under a physical object such as a watercourse, railway, road, or valley. Read the entire page →
From page 28... ... Part II: PDA of Highway Structures 30 Bridges 5.1 PDA Procedure for Bridges 1. Review the general PDA procedures detailed in Section 3.4. Read the entire page →
From page 29... ... Part II: PDA of Highway Structures 31 Bridges 6. Document all appropriate damages (none, minor, moderate, severe) Read the entire page →
From page 30... ... Part II: PDA of Highway Structures 32 Bridges 5.2 Bridge Damage States Tables 5-3 through 5-13 provide more detailed information on damage states for bridge elements 1 through 10 in Table 5-2 [Damage states are modified from Missouri DOT (2014) , O'Connor (2010) Read the entire page →
From page 31... ... Part II: PDA of Highway Structures 33 Bridges Table 5-7. Damage states for abutments and wingwalls. Read the entire page →
From page 32... ... Part II: PDA of Highway Structures 34 Bridges Minor Moderate Severe Foundation settlement 0–2 inches Foundation settlement 2–6 inches Foundation settlement over 6 inches Minor foundation scour Moderate foundation scour Severe foundation scour Low-velocity flow Moderate-velocity flow High-velocity flow Evidence of foundation movements, but net displacements are small Distinct and measurable net displacements, but repairable Distinct and measurable net displacements that are difficult to repair or unrepairable Table 5-12. Damage states for foundation. Read the entire page →
From page 33... ... Part II: PDA of Highway Structures 35 Bridges 5.3 Bridge Assessment Form Figure 5-2 shows the PDA form for bridges. Figure 5-2. Read the entire page →
From page 34... ... Part II: PDA of Highway Structures 36 Bridges Figure 5-2. (page 2/2) Read the entire page →
From page 35... ... Part II: PDA of Highway Structures 37 Tunnels Tunnels are often critical links in the transportation network as many are built when no other transportation options are feasible. The structural integrity of tunnels is critical to the operation of the transportation network. Read the entire page →
From page 36... ... Part II: PDA of Highway Structures 38 Tunnels 6.1 PDA Procedure for Tunnels The PDA can be conducted on short tunnels. However, for long tunnels (e.g., > 1,000 feet) Read the entire page →
From page 37... ... Part II: PDA of Highway Structures 39 Tunnels Table 6-1. Tunnel inspection checklist. Read the entire page →
From page 38... ... Part II: PDA of Highway Structures 40 Tunnels 6.2 Tunnel Cracking Types A crack is caused by tensile forces exceeding the tensile strength of the concrete. Cracks are categorized as follows (FHWA 2005) Read the entire page →
From page 39... ... Part II: PDA of Highway Structures 41 Tunnels Table 6-4. Damage states for spalling. Read the entire page →
From page 40... ... Part II: PDA of Highway Structures 42 Tunnels 6.4 Tunnel Assessment Form Figure 6-2 shows the PDA form for tunnels. Figure 6-2. Read the entire page →
From page 41... ... Part II: PDA of Highway Structures 43 Tunnels Figure 6-2. (page 2/2) Read the entire page →
From page 42... ... Part II: PDA of Highway Structures 44 Culverts Culverts enable water to pass below a road. They are designed for both hydraulic and structural loadings. Read the entire page →
From page 43... ... 7.1 PDA Procedure for Culverts 1. Review the general PDA procedures detailed in Section 3.4. Read the entire page →
From page 44... ... 6. Document all appropriate damages (none, minor, moderate, severe) Read the entire page →
From page 45... ... Part II: PDA of Highway Structures 47 Culverts 81/ Minor Moderate Severe Longitudinal cracks 0– inch in width Longitudinal cracks between –¼ inch in width Severe cracking and spall greater than ½ inch on culvert walls Spalls 0–¼ inch deep Spalls larger than ½ inch deep, and/or spalls have exposed rebar Spalls greater than ½ inch on culvert walls Minor separation of joints 0–1 inch Significant separation of joints between 1–3 inches Severe separation of joints greater than 3 inches Sections of culvert are partially collapsed Major corrosion of rebar 81/ Table 7-4. Damage states for concrete culvert. Read the entire page →
From page 46... ... Part II: PDA of Highway Structures 48 Culverts Minor Moderate Severe Minor corrosion and abrasion Moderate corrosion and abrasion Heavy corrosion and abrasion Minor waterway blockage due to debris Moderate obstruction due to debris Maximum waterway is blocked due to debris No deformation Ends totally/partially broken Table 7-8. Damage states for inverts. Read the entire page →
From page 47... ... Part II: PDA of Highway Structures 49 Culverts 7.3 Culvert Assessment Form Figure 7-3 shows the PDA form for culverts. Figure 7-3. Read the entire page →
From page 48... ... Part II: PDA of Highway Structures 50 Culverts Figure 7-3. (page 2/2) Read the entire page →
From page 49... ... Part II: PDA of Highway Structures 51 Walls For the purpose of this manual, walls are defined as any retaining, self-supported, or quay wall, regardless of height. In retaining walls, the primary function is to act as a retaining structure for embankments, fill slopes, or natural slopes. Read the entire page →
From page 50... ... Part II: PDA of Highway Structures 52 Walls Basic elements of a highway wall structure include the foundation system, sub-drainage system, and material. Walls themselves are made up of concrete, masonry, wood, or steel and are supported by gravity, piles, or ties to resist the geotechnical elements behind the wall. Read the entire page →
From page 51... ... Part II: PD A of H ighw ay Structures 53 W alls PR IM AR Y E LEM EN TS Pil es an d S ha s La gg ing An ch or He ad s Wi re/ Ge os yn .Fa cin g E lem en ts Bin or Cri b Co nc ret e Sh otc ret e Mo rta r Ma nu fac tur ed Br ick Bl oc k Pla ce d S ton e Sto ne Ma so nry Wa ll F ou nd ati on Ma ter ial Ot he r P rim ary Ele me nt SE CO ND AR Y E LE ME NT S Wa ll D rai ns Ar ch ite ctu ral Fa cin g Tra ffic Ba rri er/ Fe nc e Ro ad /Si de wa lk/ Sh ou lde r Up slo pe Do wn slo pe La ter al Slo pe Ve ge ta on Cu lve rt Cu rb/ Be am /D itc h Ot he r S ec on da ry Ele me nt W AL L P ER FO RM AN CE Pe rfo rm an ce Wall Type A n c h o r (AH) Anchor Tieback H-Pile XXOOOXXXXX (AM) Read the entire page →
From page 52... ... Part II: PDA of Highway Structures 54 Walls 8.1 PDA Procedure for Walls 1. Review the general PDA procedures detailed in Section 3.4. Read the entire page →
From page 53... ... Part II: PDA of Highway Structures 55 Walls Minor Moderate Severe Observation of minor distress Observations of element distress combinations that indicate wall component problems Combined element distresses indicating serious stability problems with components or global wall stability Global wall rotation, settlement, and/or overturning Table 8-4. Damage states for wall performance. Read the entire page →
From page 54... ... Part II: PDA of Highway Structures 56 Walls Minor Moderate Severe Small, localized soil displacements but no signs of significant settlement, bulging, bending, heaving, or distortion/deflection Significant localized settlement, bulging, bending, heaving, misalignment, distortion, deflection, and/or displacement Excessive settlement, bulging, bending, heaving, distortion, misalignment, deflection, and/or displacement Table 8-7. Damage states for distortion/deflection. Read the entire page →
From page 55... ... Part II: PDA of Highway Structures 57 Walls 8.3 Wall Assessment Form Figure 8-1 shows the PDA form for walls. Figure 8-1. Read the entire page →
From page 56... ... Part II: PDA of Highway Structures 58 Walls Figure 8-1. (page 2/2) Read the entire page →
From page 57... ... Part II: PDA of Highway Structures 59 Overhead Signs Overhead signs play a vital role in communicating messages to safely direct traffic. They can be sign bridges, cantilever sign structures, or mast arm structures. Read the entire page →
From page 58... ... Part II: PDA of Highway Structures 60 Overhead Signs 9.1 PDA Procedure for Overhead Signs 1. Review the general PDA procedures detailed in Section 3.4. Read the entire page →
From page 59... ... Part II: PDA of Highway Structures 61 Overhead Signs 10. Place and secure the placard and appropriate decal in the predetermined location, in accordance with Section 2.3.1 of this manual. Read the entire page →
From page 60... ... Part II: PDA of Highway Structures 62 Overhead Signs Minor Moderate Severe Minor damage or corrosion is present with no section loss Moderate damage or corrosion is present Heavy damage or corrosion of elements with localized section loss Handhole covers or post caps are missing Standing water observed inside the post Misaligned or have severe impact damage Column supports out of plumb Table 9-5. Damage states for column support. Read the entire page →
From page 61... ... Part II: PDA of Highway Structures 63 Overhead Signs Minor Moderate Severe Minor corrosion with no section loss Moderate corrosion or damage is present to one or more components Major or multiple element defects or section loss Minor misalignments Significant misalignment of components Table 9-9. Damage states for chord splice connections. Read the entire page →
From page 62... ... Part II: PDA of Highway Structures 64 Overhead Signs 9.3 Overhead Sign Assessment Form Figure 9-2 shows the PDA form for overhead signs. Figure 9-2. Read the entire page →
From page 63... ... Part II: PDA of Highway Structures 65 Overhead Signs Figure 9-2. (page 2/2) Read the entire page →

From page 26...

... This part of the field manual will discuss the specific PDA procedures and considerations for bridges, tunnels, walls, culverts, and overhead signs. Each chapter provides a general overview of the highway structure, a schematic, the PDA procedure, a list of elements, and the damage states to define minor, moderate, and severe damage levels for each element.