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Multi-State ABC Decision Tool and Economic Modeling Toni Doolen

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Multi-State ABC Decision Tool and Economic Modeling Toni Doolen Powered By Docstoc
					MULTI-STATE ABC DECISION TOOL AND ECONOMIC
                 MODELING



                       Toni Doolen, PhD



                           August 2011
    School of Mechanical, Industrial, and Manufacturing Engineering
                       Oregon State University


                                                                      1
              FHWA-sponsored pool funded study, TPF 5(221),
                     Technical Advisory Committee
 State          Members and Titles
                Benjamin Tang, P.E., Br Preservation Manager
                Steve Soltesz, Research Coordinator
  Oregon
                Dawn Mach, Bridge Fin. Analyst
                Holly Winston, Sr. Local Bridge Standards Engineer
                Mary F. Huie, Highways for LIFE, Program Coordinator
  FHWA          Tim Rogers, P.E., Division Bridge Engineer
                Nat Coley, Asset Manager

 California     Paul Chung, Sr. Bridge Engineer

   Iowa         Ahmad Abu-Hawash, Chief Structural Engineer

Minnesota       Kevin Western, Bridge Design Engineer

 Montana        David Johnson, Bridge design Engineer

   Texas        Courtney Holle, Transportation Engineer

   Utah         Daniel Hsiao, P.E., S.E., Sr. Project Manager

                Bijan Khaleghi, Design Engineer
Washington
                DeWayne Wilson, Bridge Management Engineer


                                                                       2
             Overall Project Objective
What: A tool to help analyze different alternatives and
 determine which construction approach for a specific
 bridge project is preferred. Focus is on being able to
 compare conventional and accelerated construction
 approaches.

Who: Transportation specialists and decision-makers




                                                       3
           Project Goals and Target Users
Goals of Project
  Bring Accelerated Bridge Construction (ABC) to ordinary
   (bread and butter) bridges
  Create a tool that can communicate decision rationale
  Assist users of ABC elements in making ABC standard
   process (standardization)
Target User Population
  Project managers
  Engineers
  Project owners
  Program planners

                                                             4
                        Agenda
1. Identification and organization of decision
   criteria
2. Defining decision-making criteria
3. Multi-criteria decision-making
4. Examples
5. Software to assist with analysis



                                                 5
            1. Criteria Identification
TAC team members along with research team
 developed a comprehensive list of criteria that
 are relevant to the decision of when to use ABC
 tools/methods for a project. Each criteria was
 defined and sub-criteria were defined, as
 appropriate.




                                               6
1. Criteria Organization




                           7
2. Defining Criteria (Example)
 Criteria                 Sub -Criteria                                          Definitions

                                                   This factor captures costs of user delay at a project site due to reduced speeds
                  User Delay
                                                   and/or off-site detour routes.
                                                   This factor captures costs of freight delay at a project site due to reduced speeds
                  Freight Mobility
                                                   and/or off-site detour routes.
                                                   This factor captures lost revenues due to limited access to local business
                  Revenue Loss                     resulting from limited or more difficult access stemming from the construction
                                                   activity.
 Indirect Costs
                                                   This factor captures the impact to the communities resulting from construction
                  Livability During Construction
                                                   activities. Examples include noise, air quality, and limited access.
                                                   This factor captures the safety risks associated with user exposure to the
                  Road Users Exposure
                                                   construction zone.
                  Construction Personnel           This factor captures the safety risks associated with worker exposure to
                  Exposure                         construction zone.




                                                                                                                               8
        3. Multi-Criteria Decision-Making
AHP (Analytic Hierarchy Process) is a decision-
 making technique designed to select the best
 alternative from a set of alternatives evaluated
 against several criteria.
The decision maker performs pair-wise
 comparisons that are used to develop an overall
 priority ranking for each alternative.


                                               9
                      3. Analysis Details
The hierarchy organizes the decision-making process
    The factors affecting the decision, i.e. criteria and sub-criteria,
     progress from general to particular
    A decision maker can insert or eliminate levels and elements.
     Less important criteria and sub-criteria can be dropped from
     further consideration.



                                                       New Sub-Criteria




                                                                          10
             AHP Analysis Details (continued)
Comparisons between criteria and between sub-
 criteria are performed using data from actual
 measurements or using a qualitative scale.

                                                                                       Indirect
Direct   9   8   7   6   5   4       3 2       1       2   3   4   5   6   7   8   9
                                                                                       Costs
Costs

Direct                                                                                 Schedule
         9   8   7   6   5   4   3    2    1       2       3   4   5   6   7   8   9
Costs                                                                                  Constraints


Direct                       4   3    2    1       2       3   4   5   6   7   8   9
                                                                                       Site
         9   8   7   6   5
Costs                                                                                  Constraints


                                                                                                  11
             AHP Analysis Details (continued)
  Comparisons are also used to assess the extent to
   which one alternative satisfies a criteria over another
   alternative.          Direct Costs

Alt A                                                                       Alt B
         9    8   7   6   5   4   3 2   1   2   3   4   5   6   7   8   9



                              Indirect Costs

Alt A                             3 2   1
                                                                            Alt B
         9    8   7   6   5   4             2   3   4   5   6   7   8   9
                        AHP Analysis Details
                           (continued)
      Criteria            Direct Costs        Indirect Costs      Site Constraints
    Direct Costs                 1                  0.5                  3
   Indirect Costs                2                   1                   4
  Site Constraints              0.33                0.25                 1


 To obtain the priorities (relative weights) of criteria, importance levels are
  normalized.
 Priority of each criterion is determined by averaging normalized weights.

                     Criteria            Priority
                     Direct Costs        0.320
                     Indirect Costs      0.558
                     Site Constraints    0.122

                                                                                     13
            AHP Analysis Details (continued)
 Overall priorities are calculated for each alternative after
  weighting normalized priorities for each criteria and after
  weighting the extent to which each alternative satisfies each
  criteria and sub criteria.

                  Alternative      Utility Level
                  Alt A            0.665
                  Alt B            0.335



 Select the alternative with the highest utility level (overall
  priority).
                                                                   14
          Example: Copano Bay Bridge in
                     Texas
 Connecting the cities of Rockport/Fulton and Lamar
 11,010 feet long, with a 129' wide and 75' tall
  navigation channel
 Data for this project was obtained from Texas DOT
 Alternatives Compared: Cast in Place (Conventional
  method) versus Pre-Cast Caps (ABC method)
 Best Alternative: ABC is highly preferred
 Critical Factors: Schedule Constraints and Site
  Constraints


                                                       15
Results




          16
Results




          17
         Example: Clear Creek Bridge in
                    Oregon
Located on Clear Creek, Gulick Lane
Existing Bridge length: 29’ steel girders on
 concrete vertical abutments
Data for this project was obtained from Oregon
 DOT
Alternatives Compared: Conventional
 construction versus ABC
Best Alternative: Conventional
Critical Factor: Direct Costs
                                              18
Results




          19
Results




          20
5. Software




              21
Criteria Comparisons




                       22
Results




          23
         Contact Details
       Toni L. Doolen, PhD
     Oregon State University
     doolen@engr.orst.edu
         541-737-5641

       Benjamin Tang, P.E.
  Oregon DOT, Technical Services
Benjamin.M.Tang@odot.state.or.us
         503-986-3324

                                   24

				
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