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From page 35... ... 35 4 Performance of the IBRC Bridges; Utility of the IBRC Technologies The following two sections present evidence relevant to the second task in the committee's charge: to analyze the utility, compared to conventional materials and technologies, of each of the innovative materials and technologies used in projects for bridges under the program in meeting needs for a sustainable and low life-cycle cost transportation system. The evidence comes from two types of sources: evaluations in the published engineering literature of the technologies used in Innovative Bridge Research and Construction (IBRC) Read the entire page →
From page 36... ... 36 PERFORMANCE OF BRIDGES technologies, high-performance steel (HPS) , and accelerated bridge construction (ABC) Read the entire page →
From page 37... ... PERFORMANCE OF THE IBRC BRIDGES 37 These include specified fly ash, silica fume, and ground-granulated blast furnace slag replacement as percentages of the total cementitious materials content; maximum water–cementitious materials ratio; maximum concrete permeability; and 6-ksi maximum concrete compressive strength (Russell 2004, 13, 29) Read the entire page →
From page 38... ... 38 PERFORMANCE OF BRIDGES FRP Composite Technology The technologies in this category are externally bonded FRP reinforcement; FRP deck elements; FRP beams, girders, and appurtenances; FRP rebar; and FRP prestressing tendons (strand or bar) Read the entire page →
From page 39... ... PERFORMANCE OF THE IBRC BRIDGES 39 intended to add even more years of service life. The technologies in this category that were examined in the IBRC program include three types: lowchromium, galvanized, and solid and clad stainless steel rebar. Read the entire page →
From page 40... ... 40 PERFORMANCE OF BRIDGES TABLE 4-1 Life-Cycle Cost Analysis of Epoxy-Coated and CorrosionResistant Rebar Rebar Type Epoxy Coated ASTM A1035 (low-chromium steel) ASTM A955 (stainless steel) Read the entire page →
From page 41... ... PERFORMANCE OF THE IBRC BRIDGES 41 Another life-cycle cost comparison of low-chromium steel rebar was conducted by the Michigan Department of Transportation (Kahl 2007) Read the entire page →
From page 42... ... 42 PERFORMANCE OF BRIDGES when used outside marine environments. Because the principal application of coatings and anodes has been for the repair of concrete, the literature is also lacking in life-cycle studies of these technologies when building a new bridge or installing a new bridge deck over an existing superstructure. Read the entire page →
From page 43... ... PERFORMANCE OF THE IBRC BRIDGES 43 as good as conventional construction. A state with significant experience with and implementation of ABC is Utah. Read the entire page →
From page 44... ... 44 PERFORMANCE OF BRIDGES of projects involving the replacement of bridge decks, superstructure spans, or entire bridges. The state's ABC Decision Matrix has been adopted as a bridge design standard practice in Connecticut. Read the entire page →
From page 45... ... PERFORMANCE OF THE IBRC BRIDGES 45 TABLE 4-2 Example of a Comparison of ABC and Conventional Construction Cost Project: Replacement of a bridge over a stream on a state highway Project Alternatives Conventional construction method: Integral bridge with precast abutments, wingwalls and beams; cast-in-place deck and parapets ABC method: Precast rigid frame, footings, and wingwalls User Delay Impact Comparison Average daily traffic (ADT) : 4,100 vehicles per day Delay time per vehicle during construction: 20.98 minutes Construction impact duration: Conventional construction 90 days ABC 49 days Aggregate delay: (= ADT × [delay per vehicle] Read the entire page →
From page 46... ... 46 PERFORMANCE OF BRIDGES routine inspections of the bridges, as well as observations on performance in response to interview questions. Historical inspection results were analyzed to determine if bridges that were the sites of IBRC projects exhibited accelerated or reduced rates of deterioration, as compared with experience and other analyses of National Bridge Inventory (NBI) Read the entire page →
From page 47... ... PERFORMANCE OF THE IBRC BRIDGES 47 similar traffic levels and environmental conditions. For example, Missouri project MO 2000-01 included the construction of two decks on adjacent bridges. Read the entire page →
From page 48... ... 48 PERFORMANCE OF BRIDGES design-related problems with the bulb tee girders resulted in the relatively low condition rating for the two bridges. The design of the bulb tee girders included a narrow web with inadequate space for longitudinal tendon ducts. Read the entire page →
From page 49... ... PERFORMANCE OF THE IBRC BRIDGES 49 The substructure component had an average rating of 7.1. The lowest component ratings for the substructure were two bridges with a rating of 4 (Poor) Read the entire page →

From page 35...

... 35 4 Performance of the IBRC Bridges; Utility of the IBRC Technologies The following two sections present evidence relevant to the second task in the committee's charge: to analyze the utility, compared to conventional materials and technologies, of each of the innovative materials and technologies used in projects for bridges under the program in meeting needs for a sustainable and low life-cycle cost transportation system. The evidence comes from two types of sources: evaluations in the published engineering literature of the technologies used in Innovative Bridge Research and Construction (IBRC)