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From page 165... ... 165 Conclusions and Suggested Research Overview of ABC Toolkit The ABC Toolkit developed for prefabricated elements and modular systems in the SHRP 2 R04 project consists of the following: • ABC Design standards; • Detailed design examples; • Recommended LRFD design specifications; and • Recommended LRFD construction specifications. The research team developed pre-engineered standards optimized for modular construction and accelerated bridge construction (ABC) Read the entire page →
From page 166... ... 166 • Substructure modules that have dimensions and weights suitable for highway transportation and erection using conventional equipment. • Designs and specifications that allow the contractor to selfperform the precasting of non-prestressed components. Read the entire page →
From page 167... ... 167 incorporate many innovative features that are well suited to rapid construction. Only one row of vertical piles is used, which means fewer piles. Read the entire page →
From page 168... ... 168 Precast Complete Piers Precast complete piers are also composed of separate components fabricated off site, shipped, and assembled in the field into a complete bridge pier. Piers with single-column and multiple-column configurations are common. Read the entire page →
From page 169... ... 169 weight of each module can be designed to suit transportation of components and erection methods. Erection can generally be accomplished with conventional equipment. Read the entire page →
From page 170... ... 170 construction practice, and could include greatly simplified reinforcement designs. A lab testing program was carried out to further evaluate the performance of UHPC in ABC applications in Task 10C of this project. Read the entire page →
From page 171... ... 171 Overview of ABC Design Standards Typical designs for superstructure and substructure modules have been grouped into the following span ranges: • 40 ft ≤ span ≤ 70 ft; • 70 ft ≤ span ≤ 100 ft; and • 100 ft ≤ span ≤ 130 ft. The superstructure cross section and module widths are shown for a typical two-lane bridge with shoulders having an out-to-out width of 47 ft, 2 in., as shown in Figure 4.1. Read the entire page →
From page 172... ... 172 Figure 4.1. Channel Bridge, Carpenter Road, New York State. Read the entire page →
From page 173... ... 173 • Mechanical grouted splices; • Element sizes; and • General procedure for installation of modules. Organization of ABC Design Standards The systems presented in these ABC Design standards consist of the following items, which are listed in Tables 4.1 and 4.2: • Sheets A1 through A12 44 Semi-integral abutments. Read the entire page →
From page 174... ... 174 use of conventional equipment would be the first choice for constructing a bridge designed with ABC modularized components. Unlike conventional stick-built bridges, the appropriate construction technology for rapid renewal projects built with ABC modular systems should be selected after careful consideration of project and site constraints and the choice of technologies available. Read the entire page →
From page 175... ... 175 Figure 4.2. Selection flowchart for ABC Construction Technologies. Read the entire page →
From page 176... ... 176 has been selected, the designer must integrate this technology into the bridge design. ABC Designs Built with Conventional Erection This is the typical construction method employed in most construction with prefabricated systems. Read the entire page →
From page 177... ... 177 • Component delivery occurs at the end of the existing bridge, which minimizes disruptions at the lower level of the project site. • Decreases the need to work around existing traffic and lessens the need to reduce lanes, shift lanes, or detour lanes, which in turn improves safety for both workers and the traveling public. Read the entire page →
From page 178... ... 178 Currently, economical design that uses CIP construction requires simplified fabrication with less emphasis on weight reduction. However, for ABC, shipping weights have to be minimized for economy and constructability. Read the entire page →
From page 179... ... 179 comprehensive view of how ABC Designs are performed and translated to design drawings and details. The design examples focus on the design of the modules and the connection details. Read the entire page →
From page 180... ... 180 adjacent to the corresponding design procedure. The examples are organized in a logical sequence to make them easy to follow. Read the entire page →
From page 181... ... 181 To what extent is cracking allowed in prefabricated systems during transportation and erection? What are the limiting stresses, deflections, and distortion during construction for steel and concrete components? Read the entire page →
From page 182... ... 182 www.fhwa.dot.gov, and at DOT websites listed in the following references: Caltrans, 2007; Colorado DOT, 2006; FHWA, 2010b; Florida DOT, 2007; Michigan DOT, 2007; Minnesota DOT, 2008; Montana DOT, 2009; and Ohio DOT, 2006. Innovative ABC Project Delivery Methods Innovative project delivery is a natural fit for accelerated bridge construction. Read the entire page →
From page 183... ... 183 The engineer and construction manager are generally selected on the basis of qualifications, past experience, or a determination of best value. At approximately 60% to 90% design completion, the owner and the construction manager negotiate a "guaranteed maximum price" for the construction of the project that is based on the defined scope and schedule. Read the entire page →
From page 184... ... 184 A+B projects to build confidence and acceptance of this method of procurement. Incentive/Disincentive Clauses Standard incentive/disincentive clauses (I/D clauses) Read the entire page →
From page 185... ... 185 have smaller joint widths or modified reinforcement details different than those used in the Iowa project could also be studied. Research investigating how to improve economy is critical. Read the entire page →

From page 165...

... 165 Conclusions and Suggested Research Overview of ABC Toolkit The ABC Toolkit developed for prefabricated elements and modular systems in the SHRP 2 R04 project consists of the following: • ABC Design standards; • Detailed design examples; • Recommended LRFD design specifications; and • Recommended LRFD construction specifications. The research team developed pre-engineered standards optimized for modular construction and accelerated bridge construction (ABC)