1、Designation: F 1675 03An American National StandardStandard Practice forLife-Cycle Cost Analysis of Plastic Pipe Used for Culverts,Storm Sewers, and Other Buried Conduits1This standard is issued under the fixed designation F 1675; the number immediately following the designation indicates the year o
2、foriginal adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This practice establishes a procedure for using life cycl
3、ecost (LCC) analysis techniques to evaluate alternative drainagesystem designs, using plastic pipe that satisfy the samefunctional requirements.1.2 The LCC technique measures the present value of allrelevant costs to install, operate, and maintain alternativedrainage systems such as engineering, con
4、struction, mainte-nance, rehabilitation, or replacement over a specified period oftime. The practice also accommodates any remaining residualor salvage value.1.3 The decision maker, using the results of the LCCanalysis, can then identify the alternative(s) with the lowestestimated total cost based o
5、n the present value of all costs.1.4 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitat
6、ions prior to use.2. Referenced Documents2.1 ASTM Standards:E 917 Practice for Measuring Life Cycle Costs of Buildingand Building Systems22.2 Other Standards:TM-5-802-1 Ecomomic Studies for Military ConstructionDesign Applications (12/86)3Circular No. A-94 Guidelines and Discount Rates forBenefit-Co
7、st Analysis of Federal Programs4ASTM Adjuncts:E 917 Discount Factor Tables53. Terminology3.1 Definitions:3.1.1 common costs, ncosts that are common to allalternatives in nature and amount, such as initial planning feesor future annual inspection costs.3.1.2 discount rate, nthe investors time value o
8、f money,expressed as a percent, used to convert costs occurring atdifferent times, to equivalent costs at a common point in time.3.1.3 drainage project, na project having a definable,functional drainage requirement that can be satisfied by two ormore design or construction alternatives, or both.3.1.
9、4 future costs, ncosts required to keep the systemoperating that are incurred after the project is placed in service,such as operation, maintenance, rehabilitation, or replacementcosts.3.1.5 inflation, nthe general trend or rising prices that,over time, result in the reduction of the purchasing powe
10、r ofthe dollar from year to year.3.1.6 initial cost, nthe total of all costs; such as designcosts, material purchase costs, and construction/installationcosts, that are specific to each alternative and are incurred tobring each alternative to a point of functional readiness.3.1.7 maintenance cost, n
11、the annual or periodic costs,such as inspection and cleaning to keep a drainage structurefunctioning for the project design life, but do not extend thematerial service life.3.1.8 material service life, nthe number of years ofservice a particular material, system, or structure will providebefore reha
12、bilitation or replacement is necessary.3.1.9 project design life, nthe planning horizon for theproject, expressed as the number of years of useful life requiredof the drainage structure.3.1.10 rehabilitation cost, nthe total of all costs incurredto extend the material service life of a specific alte
13、rnative.3.1.11 replacement cost, nthe total of all costs incurred toreplace a material before the end of the project design life.3.1.12 terminal value, nthe remaining value of the drain-age structure in place at the end of the project design life.4. Summary of Practice4.1 This practice outlines a pr
14、ocedure for conducting anLCC analysis of two or more drainage pipe alternatives usingplastic pipe over a specified project design life. This practice1This practice is under the jurisdiction of ASTM Committee F17 on PlasticPiping Systems and is the direct responsibility of Subcommittee F17.62 on Sewe
15、r.Current edition approved April 10, 2003. Published May 2003.Originallyapproved in 1996. Last previous edition approved in 1996 as F167596.2Annual Book of ASTM Standards, Vol 04.07.3Available from Headquarters, Department of the Army, Washington, DC.4Available from Office of Management and Budget,
16、Washington, DC.5Available from ASTM Headquarters. Order PCN 12-509179-10.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.identifies the project data and general assumptions needed forthe analysis and the method of computation.5. Sign
17、ificance and Use5.1 LCC analysis is an economic method to evaluate alter-natives that are characterized by differing cash flows over thedesignated project design life. The method entails calculatingthe LCC of each alternative capable of satisfying the functionalrequirements of the project and compar
18、ing them to determinewhich have the lowest estimated LCC over the project designlife.5.2 The LCC method is particularly suitable for determiningwhether the higher initial cost of an alternative is economicallyjustified by reductions in future costs (for example, operatingmaintenance, rehabilitation,
19、 or replacement) when compared toan alternative with lower initial costs but higher future costs. Ifa design alternative has both a lower initial cost and lowerfuture costs than other alternatives, an LCC analysis is notnecessary to show the former is the economically preferablechoice.6. Procedure6.
20、1 The procedure for performing an LCC analysis fordrainage pipe applications is as follows:6.1.1 Identify project objectives, alternatives, and con-straints (6.2).6.1.2 Establish basic assumptions (6.3).6.1.3 Compile data (6.4).6.1.4 Compute life cycle cost for each alternative (7.1).6.1.5 Evaluate
21、results (7.2).6.2 Project Objectives, Alternatives, and Constraints:6.2.1 Specify the design objective that is to be accom-plished, identify alternative systems or designs that accomplishthat objective, and identify any constraints that may limit theoptions to be considered.6.2.2 An example is the d
22、esign of a storm water drainagesystem for a residential development project. The system mustsatisfy mandated drainage system objectives, such as specifiedrainfall intensities and storm water runoff limits. Availablealternatives, such as different pipe materials and varyingconfigurations of catch bas
23、ins, ponds, or underground deten-tion chambers may have different initial costs as well asexpected future costs. The system design may be constrainedby structural and hydraulic limits such as minimum andmaximum slopes and depth of burial, limits on surface flows onstreets, etc.6.3 Basic Assumptions:
24、6.3.1 Establish the uniform assumptions to be made in theLCC analysis of all alternatives. These assumptions include theselection of the discount rate, the treatment of inflation, generalinflation rate, the project design life, and the desired compre-hensiveness of the analysis.6.3.2 Discount RateTh
25、e discount rate selected shouldreflect the owners time value of money. That is, the discountrate should reflect the rate of interest that makes the ownerindifferent between paying or receiving a dollar now or at somefuture time. The discount rate is used to convert costs occurringat different times
26、to equivalent costs at a common point in time.6.3.2.1 There is no single correct discount rate for allowners. Selection of the discount rate should be guided by therate of return on alternative investment opportunities of com-parable risk (that is, the opportunity cost of capital), or, in thecase of
27、 some public organizations, on mandated or legislatedrequirements such as that contained in OMB Circular No.A-94.6.3.2.2 The discount rate may include general price inflationover the study period. This discount rate is referred to as the“nominal” discount rate in this practice. The discount rate may
28、also be expressed as the real earning power of money over andabove general price inflation, referred to as the “real” discountrate.6.3.2.3 A nominal discount rate (dn) and the correspondingreal discount rate ( dr) are related as follows:dr51 1 dn1 1 I2 1ordn5 1 1 dr! 1 1 I! 2 1 (1)where:I = the rate
29、 of general price inflation.6.3.2.4 The same discount rate should be used in evaluatingeach design alternative. Annex A1 contains a procedure tofollow in developing the discount rate. This procedure may beapplied by those who wish to select their own values as well asthose who are required to follow
30、 mandated or legislatedrequirements.6.3.3 InflationThis practice is designed only to accommo-date a uniform rate of general inflation. Calculate the LCC inconstant dollar terms (not including general inflation) or incurrent dollar terms (including general inflation). If the latter isused, a consiste
31、nt projection of general price inflation shall beused throughout the LCC analysis, including adjustment of thediscount rate to incorporate general inflation (6.3.2.2). Thepercentage change in GNP deflator and the Producers PriceIndex are two broad indicators of general inflation.6.3.3.1 If the user
32、desires or is required to treat inflation onan incremental (differential) basis, or uniquely to each indi-vidual cost component (for example, energy costs), consulteither TM-5-802-1 or Practice E 917, respectively.6.3.4 Project Design LifeEstablish the project design life(3.1.9) from mandated public
33、 policy, legislated requirements,or selection by the owner based on situation requirements. Usethe same design life for each alternative under comparison andfor all categories of cost under consideration. The potential forfuture obsolescence, that is, the potential that future changesmay modify drai
34、nage system requirements, should be consid-ered in selecting project design life.6.3.5 ComprehensivenessThe appropriate degree of pre-cision and detail to use in an LCC analysis is dependent uponthe intended use of the analysis. A less comprehensive ordetailed analysis may be sufficient to roughly r
35、ank manyalternatives, whereas a more comprehensive analysis may benecessary to select from among a few close alternatives. In anycase, omitting significant factors from an LCC analysis dimin-ishes the usefulness of the results.6.3.6 Sensitivity AnalysisNo analysis is more precise thanthe accuracy of
36、 the data and assumptions used in the calcula-tion. When there is uncertainty regarding basic assumptions(for example, cost estimates, design life, discount rate, etc.)F 1675 032calculate the LCC for a range of assumptions. The results ofthese calculations will show the user the extent to which ther
37、esults are sensitive to variations of the key assumptions.6.4 Compiling DataCompile the data specific to eachalternative under consideration.6.4.1 Initial CostsThe estimated dollar amount of allcosts is required to bring the alternative system to a point offunctional readiness.6.4.2 Material Service
38、 LifeMaterial service life is thenumber of years of service expected of the alternative understudy, which varies depending upon the pipe material, theenvironment, effluent, and application. Potential changes inenvironmental conditions which may affect the material servicelife should be considered. U
39、se job site tests, published reports,manufacturer product data, and local experience to establishservice life for each material. If material service life is less thanthe project design life (3.1.9), the analysis shall include thefuture cost to sufficiently extend the service life throughrehabilitati
40、on or replacement, in order to at least equal theproject design life.6.4.3 Future CostsCost estimates should be made for allsignificant items that are estimated to be required to allow thedrainage system to satisfy performance requirements over theproject design life. Common costs (1.1) may be exclu
41、dedwithout affecting the relative ranking of the alternatives understudy. The cost estimates should be made in constant dollars(not including inflation) in the same time frame as the estimateof initial costs.6.4.3.1 Operating CostOperating cost is an estimate ofthe annual cost for labor, power, and
42、consumable materials andsupplies required to operate a drainage system. Except forpumped systems, most drainage systems do not have signifi-cant annual operating costs.6.4.3.2 Maintenance CostMaintenance cost includes costestimates and the frequency of any inspection, cleaning, andminor repair neces
43、sary to keep the system operating at capacityduring the project design life.6.4.3.3 Rehabilitation CostRehabilitation cost is the costof major repairs to extend the material service life to equal orexceed the project design life. If more than one rehabilitation isanticipated, the years in which the
44、rehabilitation are plannedshould be noted.6.4.3.4 Replacement CostReplacement cost is the timingand cost estimate for complete replacement of any drainagesystem component. Take care to see if the service life of thereplaced material or component will at least equal the remain-ing project design life
45、. If not, rehabilitation or further replace-ment will be necessary.6.4.3.5 Terminal ValueTerminal value is the value of thedrainage system at the end of the project design life. Thepotential residual or salvage value of a drainage system isdependent upon some of the factors considered in establishin
46、gproject design life. For example, if a storm sewer is beingevaluated and a long project design life (75 years) is used,consideration should be given to risk of future obsolescence. Ifthe likelihood of functional obsolescence is high, then theremay be no residual or salvage value. If, however, it is
47、 expectedthe material could be removed and either reused or sold, thenthe net cash value (in constant dollars) represents the terminalvalue. It is not recommended to use a residual value to reflectan economic value for any remaining material life in excess ofthe project design life. As an alternativ
48、e, if the functionalrequirements of the system under design are for an indefiniteperiod, then consideration should be given to increasing theproject design life to an appropriately higher value, where theresidual value would not significantly affect the comparison ofthe various alternatives.7. Calcu
49、lations7.1 Computing Life Cycle CostsTo compute the LCC fora drainage system, all relevant cost flows over the design life ofthe project are discounted back to the present and summed.7.1.1 Find the present value (PV) of each cost category forexample, initial cost (IC), operating and maintenance (M),rehabilitation or repair (R) and terminal value ( T) using theappropriate discount formula in this section. Then sum thesepresent values to find PVLCC, for example,PVLCC 5 PVIC 1 PVM 1 PVR 2 PVT (2)7.1.2 Initial costs are assumed to occur in the base year(year
