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From page 12... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 5 C H A P T E R 2 Literature Review and Survey Literature Review Synthesis Rutgers University led the effort of gathering references relevant to the project objectives. The references gathered included code specifications (including both local and federal domestic as well as international) Read the entire page →
From page 13... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 6 In North American structural design codes, durability-focused limit states are not explicitly identified and are addressed primarily through "deemed-to-satisfy" requirements included in concrete material specifications, crack control provisions (rebar spacing and size limitations) , and concrete cover requirements, along with guidance related to drainage, steel coatings, and the design of specific elements for replacement. Read the entire page →
From page 14... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 7 Table 1. Indicative design working life (EN 1990 2002, ISO 2012a) Read the entire page →
From page 15... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 8 contrast, the definitions offered by AASHTO and fib Bulletin 34 make no mention of maintenance. The definition offered by AS 5100.5 may be interpreted to assume "non-major" maintenance and repair will occur throughout the service life. Read the entire page →
From page 16... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 9 In response to the identified primary challenges, a framework for the service life design of bridges was developed and presented. The framework starts with bridge system selection and moves in an iterative manner through the design/selection of various components. Read the entire page →
From page 17... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 10 Of particular interest to this research project are the results of the calibration of crack control-related limit states (inclusive of the tensile stress limitations for pre-stressed concrete) Read the entire page →
From page 18... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 11 4. By selecting a shorter service life for specific elements and planning for their replacement such that their deterioration does not govern the service life of the overall bridge (e.g. Read the entire page →
From page 19... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 12 reliability indices) Read the entire page →
From page 20... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 13 W and k may be estimated by examining similar structures with similar mix, execution, and exposure or from the literature. In the case of existing structures, the product of W and k may be directly measured through material sampling and testing. Read the entire page →
From page 21... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 14 Limit State: Freeze/Thaw Damage Causing Local Loss of Mechanical Properties, Cracking, Scaling and Loss in Cross-Section - Without Deicing Agents or Sea Water The probability that freeze-thaw damage occurs without the presence of deicing agents and sea water, pfreeze/thaw damage, is taken as the probability that the temperature in the concrete during its service life T(t Read the entire page →
From page 22... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 15 Limit State: Depassivation due to Chloride Ingress (Uncracked Concrete, Marine Environment) The partial factor approach to depassivation of concrete due to chloride ingress is the same as the depassivation of concrete due to carbonation (ISO 2012) Read the entire page →
From page 23... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 16 The following section summarizes the exposure classes that are explicitly defined by the Eurocode, the Australian Bridge Design Code, ACI, the Canadian Standards Association, and the Florida DOT Structures Manual. Several definitions for different environments (e.g., marine) Read the entire page →
From page 24... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 17 Table 3. Eurocode exposure classes (EN 2004, EN 2013) Read the entire page →
From page 25... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 18 Table 3. Eurocode exposure classes (EN 2004, EN 2013) Read the entire page →
From page 26... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 19 Table 4. Eurocode limiting exposure class values for chemical attack from natural soil and ground water (EN 2013) Read the entire page →
From page 27... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 20 Table 5. AS 5100.5 exposure classes (AS 2004) Read the entire page →
From page 28... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 21 • Freezing and thawing (F) • Sulfate (S) Read the entire page →
From page 29... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 22 Table 7. CSA environmental exposures by deterioration mechanism (CSA 2014) Read the entire page →
From page 30... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 23 given by ACI, with the only difference being the additional limits for sulfate in recycled aggregates provided by CSA. Table 9. Read the entire page →
From page 31... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 24 (4) All classes of concrete exposed to sulfates shall comply with the minimum requirements of S class noted in Tables 2 and 3 (of CSA 2009) Read the entire page →
From page 32... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 25 Oregon DOT Bridge Design and Drafting Manual The Oregon Department of Transportation (ODOT) does not explicitly define exposure classes, but does provide corrosion protection provisions for marine and non-marine environments. Read the entire page →
From page 33... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 26 Additionally, VDOT specifies alternative provisions for concrete cover based on three condition classes: normal, corrosive, and marine. Corrosive environment affects cover where concrete surface is in permanent contact with corrosive soil. Read the entire page →
From page 34... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 27 Deemed-to-Satisfy and Avoidance Provisions Based on Specific Deterioration Mechanisms ISO 16204 and fib Bulletin 34 Unlike most of the other codes and standards reviewed, ISO 16204 (2012b) and fib Bulletin 34 (2006) Read the entire page →
From page 35... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 28 Table 11. ACI requirements for freeze-thaw exposure classes (ACI 2016) Read the entire page →
From page 36... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 29 (c) Silica fume, ASTM C1240, present in a blended cement †Fly ash or other pozzolans and silica fume shall constitute no more than 25 and 10 percent, respectively, of total mass of the cementitious materials. Read the entire page →
From page 37... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 30 Table 14. ACI requirements to protect against damage to concrete by external sulfate attack (ACI 2016) Read the entire page →
From page 38... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 31 can be reduced by limiting the maximum internal temperature of the concrete to 158°F at all times. If temperatures above 158°F are unavoidable, the prevention measures in Table 15 are recommended. Read the entire page →
From page 39... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 32 on concrete are summarized in Table 16 and Table 17, respectively. Sub-bullets that follow describe specific types of chemical attack in greater detail. Read the entire page →
From page 40... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 33 ‡Poor curing procedures result in flaws and cracks. #Resistance to cracking depends on strength and strain capacity. Read the entire page →
From page 41... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 34 delamination, disintegration, degradation of the cement matrix, and loss of compressive strength, among others. Mitigation strategies include low permeability, good curing, avoiding deicing exposure in the first year of service, and adequate drainage to minimize exposure time. Read the entire page →
From page 42... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 35 Table 18. ACI limits on chloride content in newly constructed concrete (ACI 2016) Read the entire page →
From page 43... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 36 Air content requirements to resist freeze-thaw attack are given in Table 19. Air content categories 1 and 2 correspond to exposure classes F-1 and F-2, respectively, from Table 9. Read the entire page →
From page 44... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 37 mitigation. For ACR, the avoidance of the use of susceptible aggregates is recommended. Read the entire page →
From page 45... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 38 PennDOT Design Manual, Part 4 PennDOT specifies the use of "Single Deck" or "Dual Deck" Protection Systems, depending on whether a bridge is designated a Federal Aid Project. Deck replacements are treated differently than new bridge designs or full bridge replacements. Read the entire page →
From page 46... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 39 – If anticipated corrosion loss is less than 1/16 in., deduct 1/16 in. minimum from the exposed surface of the pile when computing section capacity. Read the entire page →
From page 47... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 40 Table 23. Eurocode recommended limiting values for composition and properties of concrete (EN 2013) Read the entire page →
From page 48... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 41 Australian Bridge Design Code AS 5100.5 (2004) provides minimum required concrete compression strength based on the defined exposure classes. Read the entire page →
From page 49... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 42 Table 25. CSA maximum water/cement ratios (CSA 2014) Read the entire page →
From page 50... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 43 Table 26. CSA concrete material requirements (CSA 2009) Read the entire page →
From page 51... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 44 performance criteria in addition to compressive strength (Class A(HPC) Read the entire page →
From page 52... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 45 Table 28. Required concrete classes (FDOT 2017) Read the entire page →
From page 53... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 46 Texas DOT Bridge Design Manual The Texas Department of Transportation (TxDOT) specifies the use of TxDOT Class S (HPC) Read the entire page →
From page 54... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 47 Table 30. Eurocode minimum cover required for durability of reinforcement steel (EN 2004) Read the entire page →
From page 55... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 48 Table 32. Eurocode recommended structural classification modifications (EN 2004) Read the entire page →
From page 56... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 49 Table 33. AS nominal cover requirements for standard formwork and compaction (AS 2004) Read the entire page →
From page 57... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 50 Table 35. CSA concrete cover and tolerance requirements (CSA 2014) Read the entire page →
From page 58... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 51 Table 35. CSA concrete cover and tolerance requirements (CSA 2014) Read the entire page →
From page 59... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 52 Table 35. CSA concrete cover and tolerance requirements (CSA 2014) Read the entire page →
From page 60... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 53 AASHTO The AASHTO LRFD Bridge Design Specifications (2017a) provide required concrete cover dimensions for main reinforcing bars for a variety of exposure conditions (see Table 36) Read the entire page →
From page 61... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 54 Table 37. FDOT concrete cover requirements (FDOT 2017) Read the entire page →
From page 62... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 55 1 S = Slightly Aggressive; M = Moderately Aggressive; E = Extremely Aggressive 2 Short Bridges are less than or equal to 100 feet long. Long Bridges are more than 100 feet in length. Read the entire page →
From page 63... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 56 Table 39 . GDOT slab thickness and concrete cover (GDOT 2017) Read the entire page →
From page 64... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 57 Table 40. VDOT minimum concrete cover (inches) Read the entire page →
From page 65... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 58 NCHRP Synthesis 333 Russell (2004) concludes that "the most important structural design practice to reduce corrosion of reinforcement in uncracked concrete bridge decks is to provide a minimum cover to the top layer of reinforcement of 64 mm (2.5 in.) Read the entire page →
From page 66... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 59 Concrete Crack Control In general the codes and standards investigated provide two types of guidance related to crack control. The first, and most general type, defines the maximum acceptable crack width based on exposure classes and/or component type. Read the entire page →
From page 67... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 60 Table 44. Eurocode maximum bar spacing for crack control (EN 2004) Read the entire page →
From page 68... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 61 AASHTO For flexural reinforced concrete members (excluding decks) , the AASHTO LRFD Bridge Design Specifications (2017a) Read the entire page →
From page 69... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 62 • Flanges of T-Girders and Box Girders – for flanges of the reinforced T-girders and box girders, the tension reinforcement must be equally spaced across the effective width of the flange or over a width equal to 10% of the average of adjacent span lengths (whichever is smaller) Read the entire page →
From page 70... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 63 Table 46. AASHTO tensile stress limits in pre-stressed concrete at service limit state after losses (AASHTO 2014) Read the entire page →
From page 71... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 64 then this modification is not needed. Table 47 shows the average reliability indices associated with different girder types for two tensile stress limitations. Read the entire page →
From page 72... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 65 VDOT VDOT (2018a) adopts the AASHTO (2017a) Read the entire page →
From page 73... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 66 – Greater than 15 percent delaminated, patched, or cracked deck area and investigations confirm the deck deterioration is not beyond repair. – Greater than 5 percent but less than 15 percent delaminated, patched, or cracked deck area. Read the entire page →
From page 74... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 67 • barrier coatings – sealers with high viscosity, which prevents pore penetration but allows for the creation of a surface coating that blocks the pores. Sealer types were grouped as water repellents (alkylalkoxy silane, oligomeric alkylalkoxy siloxane) Read the entire page →
From page 75... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 68 Table 50. Summary of Oklahoma DOT sealer policy (Cady 1994) Read the entire page →
From page 76... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 69 performance as well as almost no documented correlation with lab performance and performance in the field. Table 51. Read the entire page →
From page 77... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 70 Table 52. Comparison of sealer generic class rankings: field tests versus lab tests (Cady 1994) Read the entire page →
From page 78... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 71 Other parameters that must be considered when selecting a sealer include service and recoating. • Service: Severe service refers to surfaces subject to traffic wear as well as direct application of deicing chemicals. Read the entire page →
From page 79... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 72 Table 53. Summary of sealer service life data from the technical literature (Cady 1994) Read the entire page →
From page 80... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 73 1. Estimate field environmental effective chloride diffusion constant, Dc, using field data or reference values (Table 54) Read the entire page →
From page 81... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 74 0 0 eq eq total t C C t− −   =     (22) Read the entire page →
From page 82... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 75 Table 55. Summary of state specification membrane requirements (Russell 2012) Read the entire page →
From page 83... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 76 Six out of nine Canadian provinces have specifications for the use of waterproofing membranes, with the Ontario provincial specification OPSS 914, Construction Specifications for Waterproofing Bridge Decks with Hot Applied Asphalt Membranes (OPSS 2009) providing the most details. Read the entire page →
From page 84... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 77 Hearn and Xi (2007) compared the service life costs of four types of reinforcement protection using the history of 82 bridges built between 1969 and 1991 using both annualized cost and present value measures: • Uncoated reinforcing bars with rigid overlay • Epoxy coated reinforcing bars and a concrete surface sealer • Uncoated reinforcing bars protected with a waterproofing membrane and bituminous overlay • Epoxy coated reinforcing bars protected with a waterproofing membrane and bituminous overlay They concluded that decks with waterproofing membranes were the least expensive. Read the entire page →
From page 85... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 78 The guidance related to coatings, in general, is more qualitative in nature than the guidance discussed previously for concrete. Notable exceptions that provide more quantitative estimates of service life do exist (e.g. Read the entire page →
From page 86... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 79 In addition, for elements that are immersed in water throughout their service life, three exposure classes are offered associated with contact to potable water, fresh water, and salt water. Table 57 provides the estimated service life of a number of common coating systems for atmospheric exposure conditions. Read the entire page →
From page 87... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 80 Table 57. Estimated service life for coating systems with atmospheric exposure (Helsel and Lanterman 2018) Read the entire page →
From page 88... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 81 24 Epoxy Zinc Epoxy Zinc/Epoxy Blast 2 7 24 17 11 11 25 Epoxy Zinc Epoxy Zinc/Epoxy/Epoxy Blast 3 11 29 20 14 14 26 Epoxy Zinc Epoxy Zinc/Polyurethane Blast 2 6 24 17 11 11 27 Epoxy Zinc Epoxy Zinc/Epoxy/Polyurethane Blast 3 10 29 20 14 14 28 Epoxy Zinc Epoxy Zinc/Epoxy/Fluorinated Polyurethane Blast 3 10 34 24 18 18 29 Organic Zinc Organic Zinc/Acrylic Waterborne/ Acrylic WB (AWWA OCS-3) Blast 3 7 21 15 11 11 30 Organic Zinc Organic Zinc/Epoxy/Polyurethane (AWWA OCS-6) Read the entire page →
From page 89... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 82 Table 58. Estimated service life for coating systems for immersive exposure (Helsel and Lanterman 2018) Read the entire page →
From page 90... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 83 In addition to this general guidance, EN 1994-2 (2005) , which addresses the design of composite steel and concrete structures, requires that steel flanges supporting concrete decks should "extend into the steelconcrete interface at least 50 mm." Eurocode also references ISO 12944-3, which provides more specific guidance related to detailing steel structures for accessibility and drainage. Read the entire page →
From page 91... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 84 exposure class, "Marine", is defined as a standalone class. The required coating systems as per CSA for superstructure and other components for these exposure classes are provided in Table 59 and Table 60, respectively. Read the entire page →
From page 92... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 85 Table 59. CSA required corrosion protection for superstructure components (CSA 2014) Read the entire page →
From page 93... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 86 Table 60. CSA required corrosion protection for other components (CSA 2014) Read the entire page →
From page 94... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 87 From a detailing standpoint, CSA provides general guidance related to the avoidance of corrosion traps and drainage. Specifically, CSA requires the following: • details that provide free air circulation for all above ground components • details that minimize exposed surface area and are free from pockets, crevices, recesses, reentrant corners, and other locations that collect and retain water, debris, and moisture. Read the entire page →
From page 95... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 88 • Structures four or more miles from the coast, regardless of superstructure exposure class, with vertical and horizontal clearances that meet the following criteria: – For structures over water  Minimum 12 ft. vertical clearance over mean or normal high water for water with chloride concentrations less than 6000 ppm  Minimum 25 ft. Read the entire page →
From page 96... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 89 addition, they state that discontinuous welds and spot welds should be avoided unless the corrosion risk in the vicinity is negligible. The standard goes on to state that the protective paint system should be accessible to allow for application, inspection, and maintenance. Read the entire page →
From page 97... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 90 – Divert roadway drainage away from the bridge structure. – Clean troughs or reseal deck joints. Read the entire page →
From page 98... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 91 Eurocode As part of the discussion of service limit states within EN 1993-2 (2006) , the following guidance related to drainage is provided: • All decks should be waterproofed and the surfaces of carriageways and footpaths should be sealed to prevent the ingress of water. Read the entire page →
From page 99... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 92 consideration should be given to conveying the water in a longitudinal storm drain affixed to the underside of the bridge and discharging it into appropriate facilities on natural ground at bridge end. In addition, AASHTO (2017a) Read the entire page →
From page 100... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 93 For bridges with a 2.0% normal crown, the designer shall detail a 4" diameter hole through the bridge deck spaced at 10 feet along the gutter line. Deck drain spacing may need to be reduced to 5 feet to assure adequate drainage on super-elevated structures. Read the entire page →
From page 101... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 94 Table 61. Replaceable elements called out in domestic/international design standards. Read the entire page →
From page 102... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 95 Light poles, minor roadside sign structures and noise walls may be manufactured more economically with a shorter design life. Ease of replacement, public safety and consequence of failure are major factors in determining a suitable design life. Read the entire page →
From page 103... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 96 PennDOT Bridge Design Manual, Part 4 PennDOT (2015) states in Article 2.5.7.1 that future widening of a structure should be considered in design: "The load carrying capacity of exterior beams shall not be less than the load carrying capacity of an interior beam, unless specifically approved by the District Bridge Engineer." The commentary to this section further indicates that the "stiffness of the interior and exterior beams should be relatively equal." fib Benchmarking of Deemed-to-Satisfy Provisions fib Bulletin 76 (2015) Read the entire page →
From page 104... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 97 Source: fib (2015) Figure 5. Read the entire page →
From page 105... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 98 Source: fib (2015) Figure 6. Read the entire page →
From page 106... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 99 The results of this benchmark show that the reliability spectrum of the deemed-to-satisfy rules for each of the countries is always broad and independent of exposure class. It was found that the lower reliability level was a result of selecting low-resistance types of cement, suggesting that the widespread reliability within each exposure class is a result of differences in material performance. Read the entire page →
From page 107... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 100 through cracks high quality of concrete cover (cover thickness ≥ 50mm, low permeability concrete, w/c ≤ 0.5) and ordinary crack width limitation (wk,cal ≤ 0.3 mm) Read the entire page →
From page 108... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 101 – Extent of cracking • Determine effects of epoxy coating, galvanizing, and other alternate reinforcing types on service life. In particular, the material effects on the chloride threshold value are needed. Read the entire page →
From page 109... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 102 The questionnaire is grouped in three parts: 1. Bridge system 2. Read the entire page →
From page 110... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 103 2. Rank the following environmental factors in the order your agency considers to have the most significant impact on bridge service life. Read the entire page →
From page 111... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 104 * Read the entire page →
From page 112... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 105 * Read the entire page →
From page 113... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 106 * Read the entire page →
From page 114... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 107 Figure 13. Average age of bridge replacement due to deterioration. Read the entire page →
From page 115... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 108 8. Based on the provided definitions above, what should be the target service life for each of the following service life categories of highway bridges? Read the entire page →
From page 116... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 109 (a) Read the entire page →
From page 117... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 110 Bridge Components 10. Rank the following bridge components in the order of most frequently repaired/replaced by your agency (1 = most frequent; 9 = least frequent) Read the entire page →
From page 118... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 111 11. What is the most common durability problem experienced by your agency in relation to concrete superstructure girders, beams, truss members, etc.? Read the entire page →
From page 119... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 112 As shown in Figure 19, corrosion of reinforcement was the most common response, followed by freezethaw attack, AAR, impact damage, abrasion, poor detailing, chemical damage, and fire damage. One respondent answered "unknown". Read the entire page →
From page 120... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 113 Figure 20. Concrete foundation durability problems indicated by respondents. Read the entire page →
From page 121... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 114 Figure 21. Concrete bridge deck durability problems indicated by respondents. Read the entire page →
From page 122... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 115 Figure 22. Steel superstructure durability problems indicated by respondents. Read the entire page →
From page 123... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 116 17. What is the most common durability problem experienced by your agency in relation to MSE and geosynthetics? Read the entire page →
From page 124... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 117 Figure 25. Joint durability problems indicated by respondents. Read the entire page →
From page 125... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 118 Design for Durability 20. For the bridge components listed below, please provide initial design strategies (e.g., specific material, detail) Read the entire page →
From page 126... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 119 * Includes coating, painting, sealing, galvanization, membranes, and repellants †Includes stainless steel, epoxy coated, and composites ‡Includes high performance concrete, low permeability concrete, high strength, admixtures, SCMs, and water/cement ratio Figure 28. Read the entire page →
From page 127... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 120 Common design strategies used by agencies for concrete bridge decks are shown in Figure 30, with type of reinforcement and concrete mix being the most selected design strategies. "Other" design strategies included pre-stressed concrete decks (3) Read the entire page →
From page 128... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 121 * Includes coating, galvanization, and metallization Figure 31. Read the entire page →
From page 129... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 122 Figure 33. Specific bearing types indicated by respondents used to increase service life. Read the entire page →
From page 130... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 123 Design strategies no longer utilized for piers and abutments are shown in Figure 35. The only designs indicated by multiple respondents were the type of abutment, which included stub and diaphragm types, and the use of timber. Read the entire page →
From page 131... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 124 Common design strategies no longer used by agencies for concrete bridge decks are shown in Figure 37. Specific types of overlays and certain types of reinforcement were mentioned the most by respondents. Read the entire page →
From page 132... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 125 Service life design strategies no longer used for bearings that were provided by respondents are shown in Figure 39. The majority of respondents mentioned specific types of bearings, including rocker bearings, pot bearings, steel sliding bearings, and fiber reinforced elastomeric pads. Read the entire page →
From page 133... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 126 Figure 40. Agency requirements for the reduction of corrosion in bridge decks. Read the entire page →
From page 134... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 127 Figure 41. Protection measures for driven piles. Read the entire page →
From page 135... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 128 26. In marine environments, or other corrosion-prone environments, what material does your agency recommend for use in primary superstructure members? Read the entire page →
From page 136... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 129  Other Fiber Reinforced Polymer reinforcement (e.g., aramid, glass, basalt)  Other The majority of respondents indicated epoxy coated reinforcement is used for substructures in corrosionprone environments, as shown in Figure 44. Read the entire page →
From page 137... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 130 Figure 45. Types of specifications used by agencies for durability design. Read the entire page →
From page 138... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 131 30. Are there any design provisions related to durability or service life not currently required in Standards used by your agency that you believe should be implemented? Read the entire page →
From page 139... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 132 Figure 48. Durability related practices to avoid in new designs. Read the entire page →
From page 140... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 133 * Includes galvanization, metallization, sealing, coating, painting, and overlays †Includes stainless steel, epoxy coated, composites, and other alternate/corrosion resistant materials ‡ Includes high performance concrete, low permeability concrete, low cracking concrete, admixtures, SCMs, fiber reinforced concrete, self consolidating concrete, strength requirements, and crack control requirements Figure 49. Read the entire page →
From page 141... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 134 * Includes load rating, superstructure analysis, substructure analysis †Includes core sampling, chloride content testing, petrographic testing, GPR, delamination testing, half cell potential, carbonation testing, and patina testing ‡ Includes corrosion/section loss, condition state, and overall deterioration/condition Figure 50. Read the entire page →
From page 142... ... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 135 reinforcement, or have altered their concrete mix designs. Rather than providing answers that arrived at a consensus of design strategies, most of the responses were directed toward a specific type of bridge element or material, such as discontinuing the use of a certain joint, bearing, or deck protection system. Read the entire page →

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... NCHRP Web-Only Document 269: Guide Specification for Service Life Design of Highway Bridges 5 C H A P T E R 2 Literature Review and Survey Literature Review Synthesis Rutgers University led the effort of gathering references relevant to the project objectives. The references gathered included code specifications (including both local and federal domestic as well as international)