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From page 9... ... NCHRP Project 03-110: Estimating the Life-Cycle Cost of Intersection Designs Final Report Page 3 Chapter 2 – Research Approach CHAPTER 2 RESEARCH APPROACH The research approach outlines the methodology for the life-cycle cost tool development, provides a summary of cost parameters used in the tool, and includes descriptions for the use cases that provided a framework for the scope of the tool. The methodology section outlines the tool's approach to addressing varying lifespans of alternatives, varying spatial scopes, and new types of intersections. Read the entire page →
From page 10... ... NCHRP Project 03-110: Estimating the Life-Cycle Cost of Intersection Designs Final Report Chapter 2 – Research Approach Page 4 2.1.1. ADDRESSING DIFFERENT LIFESPANS Comparison of design alternatives can be complicated by differences in the useful lives of intersection components. Read the entire page →
From page 11... ... NCHRP Project 03-110: Estimating the Life-Cycle Cost of Intersection Designs Final Report Page 5 Chapter 2 – Research Approach 2.1.1.1. Defining the Analysis Period The initial step in addressing intersection alternatives with different useful lives is identifying the analysis period over which costs and benefits will be quantified. Read the entire page →
From page 12... ... NCHRP Project 03-110: Estimating the Life-Cycle Cost of Intersection Designs Final Report Chapter 2 – Research Approach Page 6 cycle of less than 20 years may make it difficult to accurately capture the effects of important life-cycle differences. When the analysis period is short, the accurate estimation of terminal or salvage values becomes critical. Read the entire page →
From page 13... ... NCHRP Project 03-110: Estimating the Life-Cycle Cost of Intersection Designs Final Report Page 7 Chapter 2 – Research Approach Present Value (NPV) Equations are applied, as shown in Equations 2-1 through 2-4. Read the entire page →
From page 14... ... NCHRP Project 03-110: Estimating the Life-Cycle Cost of Intersection Designs Final Report Chapter 2 – Research Approach Page 8 n= the end of the analysis period; and r= the discount rate being used. If a terminal value is used instead of a salvage value, the same formula is used to bring it to present value. Read the entire page →
From page 15... ... NCHRP Project 03-110: Estimating the Life-Cycle Cost of Intersection Designs Final Report Page 9 Chapter 2 – Research Approach prior to the base year of analysis (i.e., the existing intersection was installed 12 years ago) Read the entire page →
From page 16... ... NCHRP Project 03-110: Estimating the Life-Cycle Cost of Intersection Designs Final Report Chapter 2 – Research Approach Page 10 Table 2-1: Continued: Project Example #1 – Comparing the Cost with Salvage Value As shown in Table 2-1, after the assumptions are outlined (Step 1) , Step 2 in the process is to identify the intersection components and to estimate the useful life, remaining useful life at the end of the analysis period, and share of the useful life remaining that can be used for salvage value. Read the entire page →
From page 17... ... NCHRP Project 03-110: Estimating the Life-Cycle Cost of Intersection Designs Final Report Page 11 Chapter 2 – Research Approach Step 3 in the example uses the information identified in Step 2, such as the cost and share of useful life of each intersection component, to calculate the salvage value for each intersection alternative. Then, using the Net Present Value of Salvage Equation (Equation 2-4) Read the entire page →
From page 18... ... NCHRP Project 03-110: Estimating the Life-Cycle Cost of Intersection Designs Final Report Chapter 2 – Research Approach Page 12 Table 2-2: Project Example #2 – Comparing the Cost with Amortized Cost Real Discount Rate (r) 4% Opening Year 2015 Base Year 2014 Base Case Constructed 2002 Construction Year 2014 Analysis Period (n) Read the entire page →
From page 19... ... NCHRP Project 03-110: Estimating the Life-Cycle Cost of Intersection Designs Final Report Page 13 Chapter 2 – Research Approach Table 2-2: Continued: Project Example #2 – Comparing the Cost with Amortized Cost As shown in Table 2-2, Project Example #2 compares the costs of Alternative 0 and Alternative 1 with amortized costs. This example scenario uses the same assumptions and intersection components that were previously identified. Read the entire page →
From page 20... ... NCHRP Project 03-110: Estimating the Life-Cycle Cost of Intersection Designs Final Report Chapter 2 – Research Approach Page 14 approximately the same as was calculated using the salvage values in Project Example #1. Project Example #3, presented in Table 2-3, takes this intersection comparison to the next step by comparing the present value of benefits for each case. Read the entire page →
From page 21... ... NCHRP Project 03-110: Estimating the Life-Cycle Cost of Intersection Designs Final Report Page 15 Chapter 2 – Research Approach Table 2-3: Continued: Project Example #3 – Calculating the Present Value of User and Social Costs Present Value of Benefits = Year User Delay Reliability Safety Operating Greenhouse Total 2014 $30,000 $5,000 $2,000 $500 $50 $37,550 2015 $30,900 $5,150 $2,040 $505 $51 $38,646 2016 $31,827 $5,305 $2,081 $510 $51 $39,773 2017 $32,782 $5,464 $2,122 $515 $52 $40,935 2018 $33,765 $5,628 $2,165 $520 $52 $42,130 2019 $34,778 $5,796 $2,208 $526 $53 $43,361 2020 $35,822 $5,970 $2,252 $531 $53 $44,628 2021 $36,896 $6,149 $2,297 $536 $54 $45,933 2022 $38,003 $6,334 $2,343 $541 $54 $47,276 2023 $39,143 $6,524 $2,390 $547 $55 $48,659 2024 $40,317 $6,720 $2,438 $552 $55 $50,083 2025 $41,527 $6,921 $2,487 $558 $56 $51,549 2026 $42,773 $7,129 $2,536 $563 $56 $53,058 2027 $44,056 $7,343 $2,587 $569 $57 $54,612 2028 $45,378 $7,563 $2,639 $575 $57 $56,212 2029 $46,739 $7,790 $2,692 $580 $58 $57,859 2030 $48,141 $8,024 $2,746 $586 $59 $59,555 2031 $49,585 $8,264 $2,800 $592 $59 $61,302 2032 $51,073 $8,512 $2,856 $598 $60 $63,100 2033 $52,605 $8,768 $2,914 $604 $60 $64,951 2034 $54,183 $9,031 $2,972 $610 $61 $66,857 2035 $55,809 $9,301 $3,031 $616 $62 $68,819 2036 $57,483 $9,581 $3,092 $622 $62 $70,840 2037 $59,208 $9,868 $3,154 $629 $63 $72,921 2038 $60,984 $10,164 $3,217 $635 $63 $75,063 2039 $62,813 $10,469 $3,281 $641 $64 $77,269 2040 $64,698 $10,783 $3,347 $648 $65 $79,540 2041 $66,639 $11,106 $3,414 $654 $65 $81,878 2042 $68,638 $11,440 $3,482 $661 $66 $84,286 2043 $70,697 $11,783 $3,552 $667 $67 $86,765 Alternative 0 - Base Case 3.) Calculate Present Value of Benefits ( ) Read the entire page →
From page 22... ... NCHRP Project 03-110: Estimating the Life-Cycle Cost of Intersection Designs Final Report Chapter 2 – Research Approach Page 16 Table 2-3: Continued: Project Example #3 – Calculating the Present Value of User and Social Costs As shown in Table 2-3, Project Example #3 uses the same overall project assumptions for comparing Alternative 0 and Alternative 1. Step 2 of this example identifies the user and social costs for each intersection for items such as emissions and delay. Read the entire page →
From page 23... ... NCHRP Project 03-110: Estimating the Life-Cycle Cost of Intersection Designs Final Report Page 17 Chapter 2 – Research Approach Table 2-4: Project Example #4 – Comparing the Benefits and Costs As shown in Table 2-4, the present value of benefits from Project Example #3 and the present value of costs from Project Example #2 are used to calculate the overall NPV of benefits for the intersection alternative comparison. The difference between benefits and costs is about $226,000, which is, therefore, the overall benefit for the alternative over the base case. Read the entire page →
From page 24... ... NCHRP Project 03-110: Estimating the Life-Cycle Cost of Intersection Designs Final Report Chapter 2 – Research Approach Page 18 Actual project scenarios may require more complex analysis and additional details to be integrated into the calculations. The methodology has the ability to analyze both simple and complex scenarios, using the same method as presented. Read the entire page →
From page 25... ... NCHRP Project 03-110: Estimating the Life-Cycle Cost of Intersection Designs Final Report Page 19 Chapter 2 – Research Approach compatible methodological definitions for the desired performance metrics. This will help to ensure that deceleration delays, control delays, and queue delays are accounted for in a similar manner. Read the entire page →
From page 26... ... NCHRP Project 03-110: Estimating the Life-Cycle Cost of Intersection Designs Final Report Chapter 2 – Research Approach Page 20 Figure 2-1: Example of Traffic Signal Influence Boundary Read the entire page →
From page 27... ... NCHRP Project 03-110: Estimating the Life-Cycle Cost of Intersection Designs Final Report Page 21 Chapter 2 – Research Approach Figure 2-2: Example of Roundabout Influence Boundary Read the entire page →
From page 28... ... NCHRP Project 03-110: Estimating the Life-Cycle Cost of Intersection Designs Final Report Chapter 2 – Research Approach Page 22 Figure 2-3: Example of Acceptable Cordon Location Read the entire page →
From page 29... ... NCHRP Project 03-110: Estimating the Life-Cycle Cost of Intersection Designs Final Report Page 23 Chapter 2 – Research Approach In practical applications, simplifying assumptions that allow an analyst to morereadily consider the isolated impacts of an intersection form may be appropriate within a saturated or coordinated system when the goal is to provide long-range, planning-level comparisons. In these cases, the lower accuracy provided with simplifying assumptions needs to be considered, as does the reasonableness of the outcome. Read the entire page →
From page 30... ... NCHRP Project 03-110: Estimating the Life-Cycle Cost of Intersection Designs Final Report Chapter 2 – Research Approach Page 24 In all cases, whether saturated or unsaturated, the identification of a cordon area should be distinguished from the modeling limits. The modeling limits within microsimulation models will sometimes require more extensive boundaries than the cordon area to properly account for arrival patterns. Read the entire page →
From page 31... ... NCHRP Project 03-110: Estimating the Life-Cycle Cost of Intersection Designs Final Report Page 25 Chapter 2 – Research Approach 2.2. ROLE OF THE LCCET IN EVALUATING INTERSECTION ALTERNATIVES The LCCET is not intended to replace existing analytic tools. Read the entire page →
From page 32... ... NCHRP Project 03-110: Estimating the Life-Cycle Cost of Intersection Designs Final Report Chapter 2 – Research Approach Page 26 Figure 2-4: Schematic: LCCET in relation to user inputs and outputs Travel demand model • Link-level travel volume forecasts by time period o Vehicles (auto, truck) o Passengers Operations analysis tools • Travel times/delays • Volumes by speed bin • Queue lengths • etc. Read the entire page →
From page 33... ... NCHRP Project 03-110: Estimating the Life-Cycle Cost of Intersection Designs Final Report Page 27 Chapter 2 – Research Approach 2.3. COSTS A description for different types of costs and for rationalizing different performance metrics into a common monetizable basis has been developed to assist implementation. Read the entire page →
From page 34... ... NCHRP Project 03-110: Estimating the Life-Cycle Cost of Intersection Designs Final Report Chapter 2 – Research Approach Page 28 2.3.1.2. Engineering Engineering costs include those directly related to the project once it has been defined. Read the entire page →
From page 35... ... NCHRP Project 03-110: Estimating the Life-Cycle Cost of Intersection Designs Final Report Page 29 Chapter 2 – Research Approach delay for non-commercial vehicles, the number of occupants in the vehicles is multiplied by the value of time of the occupants. Value of time varies for leisure or commuter traffic as well as by the income level in an area. Read the entire page →
From page 36... ... NCHRP Project 03-110: Estimating the Life-Cycle Cost of Intersection Designs Final Report Chapter 2 – Research Approach Page 30 An alternative approach to valuing travel time reliability is to use an options theoretic approach for users on a specific link, or on the entire network. The uncertainty in travel time is converted to an equivalent travel time "penalty" in terms of the following: "How large an increase in delay would a traveler be willing to accept in returned for a guarantee that the delay is no greater than a given value? Read the entire page →
From page 37... ... NCHRP Project 03-110: Estimating the Life-Cycle Cost of Intersection Designs Final Report Page 31 Chapter 2 – Research Approach 2.3.2.5. Operating Costs Operating costs are the out-of-pocket expenses perceived by users of the network for the operation and ownership of their vehicles. Read the entire page →
From page 38... ... NCHRP Project 03-110: Estimating the Life-Cycle Cost of Intersection Designs Final Report Chapter 2 – Research Approach Page 32 2.3.3.1. Delay to travelers on other parts of the network In extraordinary circumstances, such as a project that entails significant changes to a single large intersection or a project dealing with intersection treatments for an entire corridor, travelers elsewhere on the network may be affected by the project under consideration. Read the entire page →
From page 39... ... NCHRP Project 03-110: Estimating the Life-Cycle Cost of Intersection Designs Final Report Page 33 Chapter 2 – Research Approach 2.3.3.4. Right-of-Way Acquisition Right-of-way acquisition can result in costs to property owners or users in excess of the market value paid in condemnation. Read the entire page →
From page 40... ... NCHRP Project 03-110: Estimating the Life-Cycle Cost of Intersection Designs Final Report Chapter 2 – Research Approach Page 34 2.4. Read the entire page →
From page 41... ... NCHRP Project 03-110: Estimating the Life-Cycle Cost of Intersection Designs Final Report Page 35 Chapter 2 – Research Approach Table 2-5: Applications by functional area Functional area Application Agency type State DOT RTPA, CMA City, county Policy analysis, programming, budgeting Budgeting for intersection improvements in overall work program ● ● -- Establish funding policy to favor certain intersection treatments ● ○ -- Area-wide or corridor analysis Corridor study ● ● ● Rank alternative intersection treatments for a corridor or area ● ● ● Signal retiming study ● ○ ● Individual intersection analysis Intersection upgrade (e.g., 2-way or 4-way stop upgraded to signalized intersection, roundabout, or alternative form) ● ○ ● Maintenance, replacement of signals ● -- ● LCCET system maintenance Update default cost calculation parameters (capital cost, O&M cost, travel time cost, reliability cost, crash cost, environmental costs, etc.) Read the entire page →
From page 42... ... NCHRP Project 03-110: Estimating the Life-Cycle Cost of Intersection Designs Final Report Chapter 2 – Research Approach Page 36 b. Dollar valuations of travel time, stop delay, crashes, and other performance measures. Read the entire page →
From page 43... ... NCHRP Project 03-110: Estimating the Life-Cycle Cost of Intersection Designs Final Report Page 37 Chapter 2 – Research Approach a. Net benefits (present value of benefits minus present value of costs) Read the entire page →
From page 44... ... NCHRP Project 03-110: Estimating the Life-Cycle Cost of Intersection Designs Final Report Chapter 2 – Research Approach Page 38 5. Planning managers present results and recommendations to executive director and board. Read the entire page →
From page 45... ... NCHRP Project 03-110: Estimating the Life-Cycle Cost of Intersection Designs Final Report Page 39 Chapter 2 – Research Approach • Steps: 1. Engineers develop design alternatives for intersection. Read the entire page →
From page 46... ... NCHRP Project 03-110: Estimating the Life-Cycle Cost of Intersection Designs Final Report Chapter 2 – Research Approach Page 40 The research team asked those persons interviewed if a tool like the Life Cycle Cost Evaluation Tool (LCCET) would be useful for their jurisdiction and, if so, what attributes of such a tool would be most useful. Read the entire page →
From page 47... ... NCHRP Project 03-110: Estimating the Life-Cycle Cost of Intersection Designs Final Report Page 41 Chapter 2 – Research Approach • None of the agencies interviewed carry out a comprehensive benefitcost analysis of intersection treatments. For example, some agencies consider only safety, others consider only delay; and one agency that was interviewed considers only air quality improvements. Read the entire page →
From page 48... ... Final Report NCHRP Project 03-110: Estimating the Life-Cycle Cost of Intersection Designs Page 42 Table 2-6: Summary of agency interviews Agency, level, department Agency type, area covered Person(s) interviewed Types of intersection treatments considered Funding criteria Currently consider full life cycle costs and benefits? Read the entire page →
From page 49... ... NCHRP Project 03-110: Estimating the Life-Cycle Cost of Intersection Designs Final Report Page 43 Agency, level, department Agency type, area covered Person(s) interviewed Types of intersection treatments considered Funding criteria Currently consider full life cycle costs and benefits? Read the entire page →

From page 9...

... NCHRP Project 03-110: Estimating the Life-Cycle Cost of Intersection Designs Final Report Page 3 Chapter 2 – Research Approach CHAPTER 2 RESEARCH APPROACH The research approach outlines the methodology for the life-cycle cost tool development, provides a summary of cost parameters used in the tool, and includes descriptions for the use cases that provided a framework for the scope of the tool. The methodology section outlines the tool's approach to addressing varying lifespans of alternatives, varying spatial scopes, and new types of intersections.