Construction

Flowchart and Text Description

Framework for Decision-Making

High-Level Decision on Whether a Prefabricated Bridge Should Be Used in This Project

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The flowchart consists of questions within color-coded diamonds and action items within color-coded rectangles. Going vertically down the flowchart:

• The five diamonds in a horizontal line at the top of the flowchart and the diamond immediately below them are related to rapid onsite construction and are blue;
• The diamond related to other factors such as safety, environment, and repetition is tan;
• The rectangle and diamond related to costs are green;
• The rectangle for conventional construction is pink; and
• The rectangle for prefabrication is yellow.

To use the flowchart for a high-level decision on whether a prefabricated bridge should be used in the project under consideration:

1. Start at the top left corner with the question in the blue diamond, "High ADT and/or ADTT?"

   • If the answer is "Yes," go vertically down to the next question (see 2. below).
   • If the answer is "No," go to the next question to the right, "Emergency Replacement?"
   • If the answer is "Yes," go vertically down to the next question (see 2. below).
   • If the answer is "No," go to the next question to the right, "Evacuation Route, or over Railroad or Navigation Channel?"
   • If the answer is "Yes," go vertically down to the next question (see 2. below).
   • If the answer is "No," go to the next question to the right, "Required Lane Closures or Detours?"
   • If the answer is "Yes," go vertically down to the next question (see 2. below).
   • If the answer is "No," go to the next question to the right, "Impacts Critical Path of the Total Project?"
   • If the answer is "Yes," go vertically down to the next question (see 2. below).
   • If the answer is "No," go to question 3, "Do Other Factors (Safety, Environment, Repetition, etc.) Justify Prefabrication?".

2. For the question in the blue diamond, "Does Need for Rapid Onsite Construction Justify Prefabrication?"

   • If the answer is "Yes," go to the yellow rectangle at the bottom of the page, "Use Prefabrication." A "Yes" answer may be driven by agency policy or consensus among decision makers that the impact of conventional construction associated with one or more of the preceding blue diamonds would be unacceptable. The agency may support this decision by traffic modeling or other analysis methods.
   • If the answer is "No," go vertically down to the next question (see 3. below).

3. For the question in the tan diamond, "Do Other Factors (Safety, Environment, Repetition, etc.) Justify Prefabrication?"

   • If the answer is "Yes," go to the yellow rectangle at the bottom of the page, "Use Prefabrication." A "Yes" answer may result if decision makers identify a significant, adverse non-traffic impact of conventional construction that would be much less significant using prefabricated construction.
   • If the answer is "No," go vertically down to the action item in the green rectangle, "Compare Construction Costs between Conventional Bridge and Prefabricated Bridge," and then vertically down to the next question (see 4. below).

4. For the question in the green diamond, "Prefabrication Costs less than Conventional Construction?"

   • If the answer is "Yes," go to the yellow rectangle at the bottom of the page, "Use Prefabrication."
   • If the answer is "No," go to the pink rectangle to the right, "Use Conventional Construction."

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