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43 APPENDIX A Alternative-Preference Screening Matrix Example This appendix illustrates the application of the alternative- Step 1: Identification and Grouping preference screening matrix for pavement-type selection. In of Evaluation Factors the example presented, three qualifying pavement-type alter- natives are analyzed using the screening matrix for various First, the evaluation factors identified in Table A2 are evaluation scenarios. grouped as cost considerations, construction/materials con- siderations, and other considerations (see Table A4). Needs Statement Step 2: Assignment of Group and Assume that an agency has identified three pavement-type Individual Factor Weights alternatives using the process outlined in this Guide. Alter- native 1 is similar to Alternative 3, except that Alternative 3 In this step, the evaluation factors and groups are assigned includes some superior material and technological compo- appropriate weights to address the scenarios outlined in nents. Also assume that the surface types in adjacent pavement Table A3. The importance of evaluation factors and their sections of the proposed project are the same as for Alter- weights change with varying scenario goals. Table A5 presents native 2. For each alternative, the available information the factors that may require additional emphasis (i.e., higher includes the LCCA outputs and the results of economic and weights) in each scenario. noneconomic evaluation. In Scenario 1, the agency goal is to select an alternative with Table A1 lists the cost estimates for the three alternatives overall cost-effectiveness and lower initial costs; therefore, obtained from the LCCA procedure, with future costs adjusted additional emphasis is placed on both life-cycle and initial to their present values. As the life-cycle costs are within 10 per- costs. In Scenario 2, the agency priorities include not only the cent of one another, all three alternatives are qualified as cost- overall cost-effectiveness of an alternative but also the antic- effective strategies for further evaluation. ipated M&R and future user costs. In addition to cost consid- Table A2 lists the economic and noneconomic factors that erations, the agency emphasizes continuity issues related to the agency identified as important to its goals and project surface types of adjacent pavement sections. In Scenario 3, in requirements. The economic evaluation of the alternatives establishes their financial viability, while the noneconomic addition to considering life-cycle costs, the agency considers evaluation validates that these alternatives meet at least the implementing a new technology that is expected to provide minimum project requirements, as well as the agency goals better noise mitigation performance and safety features. Con- and expectations. sidering the varying agency priorities, the weights to each group In this example, three hypothetical evaluation scenarios are assigned as shown in Table A6. for pavement-type selection are considered, each of which The cost considerations are heavily weighed at 60 percent reflects emphasis on different agency goals and project needs, in all three scenarios, while the construction/materials con- as outlined in Table A3. For each of these scenarios, the user siderations and other considerations are given additional must select the most-preferred pavement-type alternative importance in Scenarios 2 and 3, respectively. (i.e., Alternative 1, 2, or 3). Regardless of the scenario, the Table A7 lists the distribution of weights assigned to indi- pavement-type selection aspects, such as the qualifying pave- vidual factors within each group for the three scenarios. The ment-type alternatives, cost estimates, and evaluation crite- table also illustrates the relative importance of individual fac- ria, should remain the same. tors across groups in the overall evaluation of the matrix. The

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44 Table A1. Results of LCCA. Cost Factor Alternative 1 Alternative 2 Alternative 3 Initial costs $3,100 $3,800 $3,500 Present value of future $792 $338 $723 rehabilitation costs Present value of future $120 $58 $84 maintenance costs Present value of user costs $171 $126 $158 Present value of total $4,012 $4,196 $4,307 agency costs Present value of total costs $4,183 $4,322 $4,465 Note: All costs are in thousands of dollars per lane mile. Table A2. Factors considered in the economic and noneconomic evaluation. Economic Factors Noneconomic Factors Initial costs Roadway/lane geometrics Noise Life-cycle costs Continuity of adjacent Subgrade soils User costs pavements Local preference Future M&R costs Continuity of adjacent Safety considerations lanes Conservation of Availability of local materials/energy materials and experience Maintenance capability Traffic during construction Future needs Stimulation of competition Experimental features Table A3. Agency goals and evaluation scenarios. Scenario Agency Goals To select a cost-effective pavement type with lower initial costs that 1 meets the agency's financial goals and noneconomic criteria To select a cost-effective pavement type that meets the agency's financial goals and noneconomic criteria 2 To minimize future costs (maintenance, rehabilitation, and road user costs) To select a pavement type compatible with those of adjacent sections To select a cost-effective pavement type with lower initial costs that meets the agency's financial goals and noneconomic criteria 3 To place additional emphasis on noise mitigation and safety features May experiment with a new technology if feasible Table A4. Grouping of economic and noneconomic factors. Construction/ Materials Cost Considerations Other Considerations Considerations Initial costs Roadway/lane geometrics Noise Life-cycle costs Continuity of adjacent Subgrade soils User costs pavements Local preference Future M&R costs Continuity of adjacent lanes Safety considerations Availability of local Conservation of materials and experience materials/energy Traffic during construction Stimulation of competition Maintenance capability Future needs Experimental features

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45 Table A5. Weighing scenarios and agency factor weights across groups were calculated by multiplying emphasis factors. individual factor weights within each group by their corre- sponding group weights provided in Table A6. Scenario Additional Emphasis in Weighing Initial costs 1 Life-cycle costs (NPV) Life-cycle costs (NPV) Step 3: Preference Rating Future rehabilitation costs of Individual Factors 2 Future maintenance costs Future user costs This step entails preference rating of individual factors for Continuity of adjacent pavements each alternative based on their relative advantages and dis- Initial cost Life-cycle cost (NPV) advantages. A comparative evaluation is presented in Tables A8 Future rehabilitation costs and A9. 3 Future maintenance costs Table A8 lists the difference in cost estimate (from the low- Noise Safety considerations est estimate for this factor among the three alternatives) as a Experimental features percentage of the lowest estimate for this factor. As noted in Table A6. Weighing scenarios and group weights. Scenario Cost Considerations, Construction/ Materials Other % Considerations, % Considerations, % 1 60 20 20 2 60 35 5 3 60 5 35 Table A7. Weighing scenarios and individual factor weights. Percent Weights within a Percent Weights across Group Factor Group Groups Scenario Scenario Scenario Scenario Scenario Scenario 1 2 3 1 2 3 Cost Initial costs 30 20 30 18 12 18 considerations Life-cycle costs 50 30 50 30 18 30 User costs 5 10 5 3 6 3 Future rehabilitation 10 25 10 6 15 6 costs Future maintenance 5 15 5 3 9 3 costs Group total 100 100 100 60 60 60 Construction / Roadway/lane 0 0 0 0 0 0 materials geometrics considerations Continuity of adjacent 30 60 30 6 21 2 pavements Continuity of adjacent 0 0 0 0 0 0 lanes Availability of local 30 10 30 6 4 2 materials and experience Traffic during 40 30 40 8 11 2 construction Group total 100 100 100 20 36 5 Other Noise 10 10 25 2 1 9 considerations Subgrade soils 20 20 0 4 1 0 Local preference 10 10 15 2 1 5 Safety considerations 15 15 25 3 1 9 Conservation of 10 10 10 2 1 4 materials/energy Stimulation of 25 25 0 5 1 0 competition Maintenance capability 10 10 0 2 1 0 Future needs 0 0 0 0 0 0 Experimental features 0 0 25 0 0 9 Group total 100 100 100 20 7 36

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46 Table A8. Comparative evaluation of economic factors. Economic Factors Difference in Cost Estimate (%) Alternative 1 Alternative 2 Alternative 3 Initial costs 0 23 13 Present value of future 135 0 114 rehabilitation costs Present value of future 107 0 45 maintenance costs Present value of user costs 35 0 25 Present value of initial and 0 5 7 future direct costs Net present value of initial 0 3 7 and future costs Note: "0" indicates the alternative having the lowest cost estimate for the specific economic factor. this table, Alternative 1 has the lowest initial costs, direct agency natives 2 and 3 are higher by more than 10 percent. Using the costs, and life-cycle costs among the alternatives; Alternative 2 rating criteria, Alternative 1 is rated "high" and the other alter- has the lowest future M&R costs and user costs; Alternative 3 natives are rated "low" for the initial cost factor. generally ranks between Alternatives 1 and 2, except in the area Table A10 lists the evaluation factors considered in this of life-cycle costs. example and their ratings for each of the three alternatives. Table A9 compares the relative advantages and disadvan- This set of ratings is common to the three scenarios considered. tages of the alternatives in terms of noneconomic factors. Alternative 2 has advantages over the others in terms of con- Step 4: Scoring Pavement-Type tinuity of adjacent pavement but is at a disadvantage regard- Alternatives ing subgrade conditions and recycling potential. Alternative 3 is similar to Alternative 1 in many aspects, but it offers better First, the ratings are converted to numerical scores. Next, for noise mitigation properties and safety features (such as skid each alternative, the unweighted numerical scores are adjusted resistance and reflectivity) than Alternatives 1 and 2. to weighted scores using the weights tabulated in Table A7. Next, we assign preference ratings to evaluation factors The sum of the weighted scores of factors within each group based on the advantages that a given alternative offers. In this is the unweighted score for that group. example, the rating criteria and rating scheme presented in Using the group weights tabulated in Table A6, the un- Chapter 5 are used. Alternative 1 has the lowest initial cost weighted group scores are adjusted to weighted group scores. among the alternatives (see Table A8); the initial costs of Alter- The total score of each alternative is then calculated by sum- Table A9. Comparative evaluation of noneconomic factors. Noneconomic Factors Alternative 1 Alternative 2 Alternative 3 Roadway/lane geometrics No issues No issues No issues Continuity of adjacent Different but no issues Same as adjacent Different but no issues pavements pavements Continuity of adjacent lanes No issues No issues No issues Availability of local No issues No issues No issues materials and experience Traffic during construction Easy to accommodate Somewhat difficult to Easy to accommodate accommodate Noise Moderate noise levels Increased noise levels Lower noise levels Subgrade soils No major issues Some issues No major issues Local preference No preference No preference Some preference Safety considerations Good skid resistance Good reflectivity but Better reflectivity and but poor reflectivity poor skid resistance skid resistance Conservation of materials/ More recycling Little recycling More recycling energy possibilities possibilities possibilities Stimulation of competition Competition is Competition is Competition is encouraged encouraged encouraged Maintenance capability Common experience Common experience Common experience Future needs Easy to accommodate Easy to accommodate Easy to accommodate Experimental features Common technology Common technology No local experience

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47 Table A10. Ratings of economic and noneconomic factors. Group Factor Alternative 1 Alternative 2 Alternative 3 Cost Initial costs High Low Low considerations Life-cycle costs High High High User costs Low High Low Future rehabilitation costs Low High Low Future maintenance costs Low High Low Construction/ Roadway/lane geometrics No difference No difference No difference materials Continuity of adjacent considerations Medium-high High Medium-high pavements Continuity of adjacent lanes No difference No difference No difference Availability of local materials No difference No difference No difference and experience Traffic during construction Medium-high Medium Medium-high Other Noise Medium Low-medium High considerations Subgrade soils Medium-high Medium Medium-high Local preference Medium Medium High Safety considerations Medium Medium High Conservation of materials/ Medium-high Low-medium Medium-high energy Stimulation of competition High High High Maintenance capability No difference No difference No difference Future needs No difference No difference No difference Experimental features Low Low High ming the weighted group scores of that alternative. These cal- changes in agency goals and project needs. In Scenario 1, culations are repeated for the three scenarios considered in Alternative 1 is the preferred alternative, largely because of this example. Table A11 summarizes the total scores of each the advantages it provides in initial costs. In Scenario 2, alternative-scenario combination and provides the breakdown Alternative 2 emerged as the preferred alternative with more of weighted group scores. Tables A12 through A14 present the weighing on future costs and the surface type continuity completed worksheets of the screening matrix for Scenarios 1, factor. 2, and 3, respectively. In Scenario 3, there apparently is no major difference in scores between Alternative 1 and Alternative 3. Where two alternatives are comparable, both could be selected as candi- Step 5: Interpreting Results dates for alternative bidding; however, since the agency priori- The alternative with the highest score can be selected as ties in Scenario 3 focus on experimenting with new technology the most-preferred alternative for each scenario. Note that and achieving superior noise and safety performance, Alter- the outcomes in these scenarios are different, reflecting native 3 is selected as the most preferred alternative. Table A11. Summary of screening matrix scores. Alternative Alternative Alternative Preferred Scenario Group 1 2 3 Alternative Cost considerations 50.4 45.6 36.0 Construction/materials 11.2 10.8 11.2 1 considerations 1 Other considerations 14.0 12.0 16.8 Total score 75.6 68.4 64.0 Cost considerations 36.0 50.4 26.4 Construction/materials 25.2 27.3 25.2 2 considerations 2 Other considerations 3.5 3.0 4.2 Total score 64.7 80.7 55.8 Cost considerations 50.4 45.6 36.0 Construction/materials 2.8 2.7 2.8 3 considerations 3 Other considerations 18.2 15.1 34.3 Total score 71.4 63.4 73.1 Note: All values in percent. Highest total scores shaded.

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48 Table A12. Alternative-preference screening matrix worksheet for Scenario 1. Alternative 1 Alternative 2 Alternative 3 Factor Factors and Groups Weighted Weighted Weighted Weight Rating Rating Rating Score Score Score Group A. Cost considerations Initial costs 3 0 .0 Hig h 3 0 .0 Low 6 .0 Low 6 .0 Life cycle costs 50.0 High 50.0 High 50.0 High 50.0 User costs 5.0 Low 1.0 High 5.0 Low 1.0 Future rehabilitation costs 10.0 Low 2.0 High 10.0 Low 2.0 Future maintenance costs 5.0 Low 1.0 High 5.0 Low 1.0 Group A unweighted total 100 84.0 76.0 60.0 Group B. Construction/materials considerations Roadway/lane geometrics 0 No difference 0 .0 No difference 0 .0 No difference 0 .0 Continuity of adjacent pavements 30 Medium-high 24.0 High 30.0 Medium-high 24.0 Continuity of adjacent lanes 0 No difference 0.0 No difference 0.0 No difference 0.0 Availability of local materials and 30 No difference 0.0 No difference 0.0 No difference 0.0 experience Traffic during construction 40 Medium-high 32.0 Medium 24.0 Medium-high 32.0 Group B unweighted total 100 56.0 54.0 56.0 Group C. Other considerations Noise 10 Medium 6.0 Low-medium 4.0 High 10.0 Subgrade soils 20 Medium-high 16.0 Medium 12.0 Medium-high 16.0 Local preference 10 Medium 6.0 Medium 6.0 High 10.0 Safety considerations 15 Medium 9.0 Medium 9.0 High 15.0 Conservation of materials/energy 10 Medium-high 8.0 Low-medium 4.0 Medium-high 8.0 Stimulation of competition 25 High 25.0 High 25.0 High 25.0 Maintenance capability 10 No difference 0 .0 No difference 0 .0 No difference 0 .0 Future needs 0 No difference 0.0 No difference 0.0 No difference 0.0 Experimental features 0 Low 0.0 Low 0.0 High 0.0 Group C unweighted total 100 70.0 60.0 84.0 Group Group Group Group Group Group Group Subtotals Weights Unweighted Weighted Unweighted Weighted Unweighted Weighted Total Total Total Total Total Total A. Cost considerations 60 84.0 50.4 76.0 45.6 60.0 36.0 B. Construction/materials considerations 20 56.0 11.2 54.0 10.8 56.0 11.2 C. Other considerations 20 70.0 14.0 60.0 12.0 84.0 16.8 Grand total 100 75.6 68.4 64.0 Note: All values in percent.

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49 Table A13. Alternative-preference screening matrix worksheet for Scenario 2. Alternative 1 Alternative 2 Alternative 3 Factor Factors and Groups Weighted Weighted Weighted Weight Rating Rating Rating Score Score Score Group A. Cost considerations Initial costs 20 Hig h 2 0 .0 Low 4 .0 Low 4 .0 Life cycle costs 30 High 30.0 High 30.0 High 30.0 User costs 10 Low 2.0 High 10.0 Low 2.0 Future rehabilitation costs 25 Low 5.0 High 25.0 Low 5.0 Future maintenance costs 15 Low 3.0 High 15.0 Low 3.0 Group A unweighted total 100 60.0 84.0 44.0 Group B. Construction/materials considerations Roadway/lane geometrics 0 No difference 0 .0 No difference 0 .0 No difference 0 .0 Continuity of adjacent pavements 60 Medium-high 48.0 High 60.0 Medium-high 48.0 Continuity of adjacent lanes 0 No difference 0.0 No difference 0.0 No difference 0.0 Availability of local materials and 10 No difference 0.0 No difference 0.0 No difference 0.0 experience Traffic during construction 30 Medium-high 24.0 Medium 18.0 Medium-high 24.0 Group B unweighted total 100 72.0 78.0 72.0 Group C. Other considerations Noise 10 Medium 6.0 Low-medium 4.0 High 10.0 Subgrade soils 20 Medium-high 16.0 Medium 12.0 Medium-high 16.0 Local preference 10 Medium 6.0 Medium 6.0 High 10.0 Safety considerations 15 Medium 9.0 Medium 9.0 High 15.0 Conservation of materials/energy 10 Medium-high 8.0 Low-medium 4.0 Medium-high 8.0 Stimulation of competition 25 High 25.0 High 25.0 High 25.0 Maintenance capability 10 No difference 0 .0 No difference 0 .0 No difference 0 .0 Future needs 0 No difference 0.0 No difference 0.0 No difference 0.0 Experimental features 0 Low 0.0 Low 0.0 High 0.0 Group C unweighted total 100 70.0 60.0 84.0 Group Group Group Group Group Group Group Subtotals Weights Unweighted Weighted Unweighted Weighted Unweighted Weighted Total Total Total Total Total Total A. Cost considerations 60 60.0 36.0 84.0 50.4 44.0 26.4 B. Construction/materials considerations 35 72.0 25.2 78.0 27.3 72.0 25.2 C. Other considerations 5 70.0 3.5 60.0 3.0 84.0 4.2 Grand total 100 64.7 80.7 55.8 Note: All values in percent.

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50 Table A14. Alternative-preference screening matrix worksheet for Scenario 3. Alternative 1 Alternative 2 Alternative 3 Factor Factors and Groups Weighted Weighted Weighted Weight Rating Rating Rating Score Score Score Group A. Cost considerations Initial costs 30 Hig h 3 0 .0 Low 6 .0 Low 6 .0 Life cycle costs 50 High 50.0 High 50.0 High 50.0 User costs 5 Low 1.0 High 5.0 Low 1.0 Future rehabilitation costs 10 Low 2.0 High 10.0 Low 2.0 Future maintenance costs 5 Low 1.0 High 5.0 Low 1.0 Group A unweighted total 100 84.0 76.0 60.0 Group B. Construction/materials considerations Roadway/lane geometrics 0 No difference 0 .0 No difference 0 .0 No difference 0 .0 Continuity of adjacent pavements 30 Medium-high 24.0 High 30.0 Medium-high 24.0 Continuity of adjacent lanes 0 No difference 0.0 No difference 0.0 No difference 0.0 Availability of local materials and 30 No difference 0.0 No difference 0.0 No difference 0.0 experience Traffic during construction 40 Medium-high 32.0 Medium 24.0 Medium-high 32.0 Group B unweighted total 100 56.0 54.0 56.0 Group C. Other considerations Noise 25 Medium 15.0 Low-medium 10.0 High 25.0 Subgrade soils 0 Medium-high 0.0 Medium 0.0 Medium-high 0.0 Local preference 15 Medium 9.0 Medium 9.0 High 15.0 Safety considerations 25 Medium 15.0 Medium 15.0 High 25.0 Conservation of materials/energy 10 Medium-high 8.0 Low-medium 4.0 Medium-high 8.0 Stimulation of competition 0 High 0.0 High 0.0 High 0.0 Maintenance capability 0 No difference 0 .0 No difference 0 .0 No difference 0 .0 Future needs 0 No difference 0.0 No difference 0.0 No difference 0.0 Experimental features 25 Low 5.0 Low 5.0 High 25.0 Group C unweighted total 100 52.0 43.0 98.0 Subtotals Group Group Group Group Group Group Group Weights Unweighted Weighted Unweighted Weighted Unweighted Weighted Total Total Total Total Total Total A. Cost considerations 60 84.0 50.4 76.0 45.6 60.0 36.0 B. Construction/materials considerations 20 56.0 2.8 54 2.7 56 2.8 C. Other considerations 20 52.0 18.2 43 15.1 98 34.3 Grand total 100 71.4 63.4 73.1 Note: All values in percent.