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From page 56... ... 56 C h a p t e r 4 4.1 Introduction Deterioration and a degradation of serviceability indicated by a reduction in usable capacity (either by a change in rating or a change in reliability index) are not interchangeable terms, although they may be related for some elements or systems. Read the entire page →
From page 57... ... 57 Table 4.1. Rating Prediction Equations and Graphs for Nine Categories of Bridges 2.00 3.00 4.00 5.00 6.00 7.00 8.00 9.00 10.00 0 20 40 60 80 100 120 Ra tin g Time (years) Read the entire page →
From page 58... ... 58 Table 4.1. Rating Prediction Equations and Graphs for Nine Categories of Bridges 2.00 3.00 4.00 5.00 6.00 7.00 8.00 9.00 10.00 0 20 40 60 80 100 120 Ra tin g Time (years) Read the entire page →
From page 59... ... 59 Table 4.1. Rating Prediction Equations and Graphs for Nine Categories of Bridges 2.00 3.00 4.00 5.00 6.00 7.00 8.00 9.00 10.00 0 20 40 60 80 100 120 Ra tin g Time (years) Read the entire page →
From page 60... ... 60 not be found in the reference. Non-Interstate, RC, and lowtraffic bridges all have an estimated service life of approximately 80 years, and bridges in the medium-traffic category have the longest estimated service life (approximately 90 years) Read the entire page →
From page 61... ... 61 (2004) , the constant term in the prediction equation is always 9; this assumes that the bridge component was in perfect condition when new. Read the entire page →
From page 62... ... 62 Non-Interstate bridges have a longer period during which the rating does not change significantly; the concrete bridge rating is higher than the steel bridge rating during this plateau period and throughout most of the service life. Concrete bridges are shown to have longer deck service lives than steel bridges. Read the entire page →
From page 63... ... 63 Table 4.3. Nebraska Deterioration Models 2.00 3.00 4.00 5.00 6.00 7.00 8.00 9.00 10.00 0 20 40 60 80 100 120 Ra tin g Time (years) Read the entire page →
From page 64... ... 64 shown in Figure 4.7. For the deck condition ratings, the Bolukbasi et al. Read the entire page →
From page 65... ... 65 [identified as NEDOR (Nebraska Department of Roads) in Figure 4.8] Read the entire page →
From page 66... ... 66 service lives. The prediction equations provide an estimated service life for the deck, superstructure, and substructure. Read the entire page →
From page 67... ... 67 Table 4.7. Service Life Comparison: Non-Interstate Bridges Equation Service Life (years) Read the entire page →
From page 68... ... 68 substructure. The estimated service lives, or the predicted times until a condition rating of 3 is achieved, are provided in Table 4.8. Read the entire page →
From page 69... ... 69 4.6 agrawal and Kawaguchi (2009) A 2009 report by Agrawal and Kawaguchi provides regression equations relating condition rating (CR) Read the entire page →
From page 70... ... 70 10,175 and 25,457 tons) , high (between 16,969 and 40,195 tons) Read the entire page →
From page 71... ... 71 Table 4.10. Regression Equations and Graphs Based on New York State Bridge Data 2.00 2.50 3.00 3.50 4.00 4.50 5.00 5.50 6.00 6.50 7.00 0 20 40 60 80 100 120 Ra tin g Time (years) Read the entire page →
From page 72... ... 72 (continued) Table 4.10. Read the entire page →
From page 73... ... 73 Table 4.10. Regression Equations and Graphs Based on New York State Bridge Data 2.00 2.50 3.00 3.50 4.00 4.50 5.00 5.50 6.00 6.50 7.00 0 20 40 60 80 100 120 Ra tin g Time (years) Read the entire page →
From page 74... ... 74 Table 4.10. Regression Equations and Graphs Based on New York State Bridge Data 2.00 2.50 3.00 3.50 4.00 4.50 5.00 5.50 6.00 6.50 7.00 0 20 40 60 80 100 120 R at in g Time (years) Read the entire page →
From page 75... ... 75 Table 4.10. Regression Equations and Graphs Based on New York State Bridge Data 2.00 2.50 3.00 3.50 4.00 4.50 5.00 5.50 6.00 6.50 7.00 0 20 40 60 80 100 120 Ra tin g Time (years) Read the entire page →
From page 76... ... 76 Table 4.10. Regression Equations and Graphs Based on New York State Bridge Data 2.00 2.50 3.00 3.50 4.00 4.50 5.00 5.50 6.00 6.50 7.00 0 20 40 60 80 100 120 Ra tin g Time (years) Read the entire page →
From page 77... ... 77 Table 4.10. Regression Equations and Graphs Based on New York State Bridge Data 2.00 2.50 3.00 3.50 4.00 4.50 5.00 5.50 6.00 6.50 7.00 0 20 40 60 80 100 120 Ra tin g Time (years) Read the entire page →
From page 78... ... 78 Table 4.10. Regression Equations and Graphs Based on New York State Bridge Data 2.00 2.50 3.00 3.50 4.00 4.50 5.00 5.50 6.00 6.50 7.00 0 20 40 60 80 100 120 Ra tin g Time (years) Read the entire page →
From page 79... ... 79 Table 4.11. Abutment Component Estimated Service Lives Component Service Life (years) Read the entire page →
From page 80... ... 80 Component Service Life (years) Deck Curb Granite or stone 75.6 Steel plate 75.9 Timber 58.3 Concrete 66.9 Primary Member Slab, box, or box channel 67.8 Tee or I-beam 77.3 Rolled beam 76.7 Plate girder 82.9 Truss 56.9 Deck arch 65.7 Metal pipe arch 87.0 Frame 72.8 Box culvert 79.5 Pipe culvert 61.0 Overall Superstructure Slab 75.4 Multistringer or beam 76.0 Girder or floorbeam 76.6 Tee beam 75.6 Box beam or girder 68.9 Frame 77.4 Culvert 76.0 Through truss 65.5 Deck arch 77.9 Secondary Member Slab, box, or box channel 82.8 Tee or I-beam 53.2 Note: NA = not available. Read the entire page →
From page 81... ... 81 Table 4.14. Transportation Systems Center Prediction Equations 2.00 3.00 4.00 5.00 6.00 7.00 8.00 9.00 10.00 0 20 40 60 80 100 120 R at in g Time (years) Read the entire page →
From page 82... ... 82 Table 4.15. Coastal Substructure Condition Rating Prediction Equations 2.00 3.00 4.00 5.00 6.00 7.00 8.00 9.00 10.00 0 20 40 60 80 100 120 R at in g Time (years) Read the entire page →
From page 83... ... 83 Table 4.15. Coastal Substructure Condition Rating Prediction Equations 2.00 3.00 4.00 5.00 6.00 7.00 8.00 9.00 10.00 0 20 40 60 80 100 120 R at in g Time (years) Read the entire page →
From page 84... ... 84 Table 4.16. Substructure Condition Rating Prediction Equations by Region 2.00 3.00 4.00 5.00 6.00 7.00 8.00 9.00 10.00 0 20 40 60 80 100 120 Ra tin g Time (years) Read the entire page →
From page 85... ... 85 Table 4.16. Substructure Condition Rating Prediction Equations by Region 2.00 3.00 4.00 5.00 6.00 7.00 8.00 9.00 10.00 0 20 40 60 80 100 120 R at in g Time (years) Read the entire page →
From page 86... ... 86 Table 4.17. Piecewise Linear Condition Rating Equations and Coefficients 2.00 3.00 4.00 5.00 6.00 7.00 8.00 9.00 10.00 0 20 40 60 80 100 120 R at in g Time (years) Read the entire page →
From page 87... ... 87 Table 4.18. Exponential Best-Fit Graphs and Parameters 2.00 3.00 4.00 5.00 6.00 7.00 8.00 9.00 10.00 0 20 40 60 80 100 120 Ra tin g Time (years) Read the entire page →
From page 88... ... 88 4.8 Massachusetts DOt The Massachusetts DOT conducted a study of its bridges to gain a better understanding of the dynamics of how bridges age and deteriorate. This knowledge is intended to be used to plan strategies for bridge work and to determine required levels of funding. Read the entire page →
From page 89... ... 89 presented studies. The same process could be used to develop additional equations based on ADTT, location, or owner if the required data were available. Read the entire page →
From page 90... ... 90 analysis of the number of bridges that were in those two categories for each year from 2002 through 2009. These equations were used to predict the number of fair and satisfactory bridges in future years. Read the entire page →
From page 91... ... 91 structurally deficient bridges for a given year was estimated by multiplying the transitional probability by the predicted number of fair or satisfactory bridges for that year. The cost model was calibrated with actual project costs and considered the costs for a full replacement versus a preservation project. Read the entire page →
From page 92... ... 92 The second and third rows of Figure 4.19 assume that 1.59 and 1.93 times as much money is available for structurally deficient bridges. The 1.53 funding level will trend to a steady state number of structurally deficient bridges. Read the entire page →
From page 93... ... 93 The highway evaluation factor is a measure of the functionality of the bridge and considers the ADT, detour length, functional classification, load-carrying restrictions, and deck geometry deficiencies. The categories within each variable are given a value between 1 and 5; the average value for the five variables is determined and then divided by five and multiplied by 100 to achieve a percentage value. Read the entire page →

From page 56...

... 56 C h a p t e r 4 4.1 Introduction Deterioration and a degradation of serviceability indicated by a reduction in usable capacity (either by a change in rating or a change in reliability index) are not interchangeable terms, although they may be related for some elements or systems.