pavement type selection for highway rehabilitation …docs.trb.org/prp/11-1127.pdf11-1127: lee, kim,...

11-1127: Lee, Kim, and Harvey 1

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Pavement Type Selection for Highway Rehabilitation Based on a Life-Cycle Cost Analysis: 2

Validation of California Interstate 710 Project (Phase 1) 3

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By Eul-Bum (E.B.) Lee, Changmo Kim, and John T. Harvey 6

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Submitted to the Committee on Pavement Rehabilitation (AFD 70) 9

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Paper No: 11-1127 12

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Eul-Bum (E.B.) Lee, Ph.D., P.E., P.M.P. 16

Associate Researcher 17

University of California, Berkeley 18

Institute of Transportation Studies (UCPRC) 19

1353 S. 46th Street, Bldg. 452 20

Richmond, CA 94804 21

Phone: 510-665-3637, Fax: 510-665-3562 22

Email: [email protected] 23

24

Changmo Kim, Ph.D. (Corresponding Author) 25

Postdoctoral Researcher 26

University of California Pavement Research Center 27

3327 Apiary Road, Davis, CA 95616 28

Phone: 530-752-5363, Fax: 530-752-7872 29


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and 32

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John T. Harvey, Ph.D., P.E. 34

Professor 35

University of California, Davis 36

Department of Civil & Environmental Engineering 37

Engineering III, Room 3139, 38

One Shields Avenue, Davis, CA 95616 39

Phone: 530-754-6409, Fax: 530-752-7872 40


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Total Words: 7,056 = Abstract (250) + Text (5,056) + Figure (1,000) + Tables (750) 46

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For the 90th Annual Meeting of the Transportation Research Board 48

January 23-27, 2011, Washington, D.C. 49

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TRB 2011 Annual Meeting Paper revised from original submittal.


ABSTRACT 1

Life-cycle cost analysis (LCCA) for highway projects is an analytical technique that uses economic 2

principles in order to evaluate long-term alternative investment options, especially for comparing the 3

value of alternative pavement structures and strategies. Recently, the California Department of 4

Transportation mandated LCCA implementation to evaluate the cost effectiveness of pavement design 5

alternatives for highway projects in the state. An LCCA approach, as reported in this paper, was utilized 6

for the validation of the pavement design on the I-710 Long Beach rehabilitation project with three 7

alternative pavement types: (1) Innovative (long-life) asphalt concrete pavement (ACP), (2) Standard-life 8

ACP, and (3) Long-life portland cement concrete pavement (PCCP). The LCCA followed Caltrans 9

procedure and incorporated information filed by the project team. The software tools CA4PRS 10

(Construction Analysis for Pavement Rehabilitation Strategies) and RealCost were used for the 11

quantitative estimates of construction schedule, work zone user cost, and agency cost for initial and future 12

maintenance and rehabilitation activities. Conclusions from the LCCA supported the use of the 13

Innovative ACP alternative, the one actually implemented in the I-710 Long Beach project (Phase 1), as it 14

had the lowest life-cycle costs over the 60-year analysis period. For example, the life-cycle agency cost 15

for the Innovative ACP alternative ($31.2 million) was about $13 million more cost-effective than that of 16

the Standard ACP alternative ($44 million) and about $38 million less expensive than the Long-life PCCP 17

alternative ($69.6 million). Utilization of the proposed computer tool-aided LCCA procedure would 18

contribute substantial economic and environmental benefits for nationwide highway projects, especially 19

rehabilitation and reconstruction. 20

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INTRODUCTION 1

Life-cycle Cost Analysis (LCCA) is an analytical technique that uses economic principles to evaluate 2

long-term alternative investment options in highway construction. LCCA accounts for costs relevant to 3

the sponsoring agency, owner, facility operator, and roadway user that will occur throughout the life of an 4

alternative. Relevant costs include those for initial construction, for future maintenance and rehabilitation, 5

and user costs (time delay and vehicle operation costs in the work zone). The LCCA analytical process 6

helps to identify the lowest cost-alternative that will accomplish a highway project’s objectives by 7

providing critical information for the overall decision-making process. For the last decade, LCCA has 8

been emphasized as much as the initial project cost analysis in evaluating the design and construction 9

plans for highway projects. 10

Recently, the California Department of Transportation (Caltrans) mandated implementation of 11

LCCA in order to evaluate the cost effectiveness of alternative pavement designs for new roadways and 12

for existing roadways that require Capital Preventive Maintenance (CAPM), rehabilitation, or 13

reconstruction (1). The Caltrans Highway Design Manual (HDM) Topics 612 and 619 identify situations 14

where an LCCA must be performed to assist in determining the most appropriate alternative for a project 15

(2). Since the cost impacts of a project’s life-cycle are fully taken into account when making project-level 16

decisions for pavements, Caltrans practice is to perform an LCCA when scoping a project (Project 17

Initiation Document phase). 18

Many researchers and practitioners have been developing LCCA concepts and computer tools to 19

undertake the most efficient cost comparison of alternatives. Papagiannakis and Delwar developed a 20

computer model to perform LCCA of roadway pavement, analyzing both agency and user costs. Their 21

software accepts inputs from a pavement management database and carries out pavement LCCA on both 22

network-wide and project-specific levels (3). Rather than considering user delay and future maintenance 23

and rehabilitation (M&R) costs, this software calculates the net annualized savings in user costs as the 24

benefit that result from reducing pavement roughness (e.g., vehicle depreciation, maintenance, and repair, 25

tires, and cargo damage) from its current condition to that in the end year of the life-cycle. 26

Salem et al. introduced a risk-based probabilistic approach to predict probabilities of the 27

alternative occurrence of different life-cycle costs on infrastructure construction and rehabilitation. Their 28

model predicts the probability of time of infrastructure failure to build alternatives (4). Using the Florida 29

and Washington State Department of Transportation (DOT) project databases, Gransberg and Molenaar 30

developed best-value award algorithms of life-cycle cost for design/build highway pavement projects (5). 31

Labi and Sinha studied the cost effectiveness of different levels of life-cycle preventive maintenance 32

(PM) for three asphalt concrete (AC) functional class families and presented a methodology to determine 33

optimum PM funding levels based on maximum pavement life (6). 34

In 2002, the Federal Highway Administration (FHWA) first published an LCCA primer to 35

provide sufficient background and demonstrations for transportation officials (7). In addition, in 2004 the 36

FHWA distributed an LCCA software tool, RealCost (Version 2.1), to support practitioners performing 37

LCCA for highway projects (8). The Caltrans Office of Pavement Management and the University of 38

California Pavement Research Center (UCPRC) have enhanced RealCost software and customized it for 39

California (1) to add to its analytical capability for cost estimation, (2) to improve work zone traffic 40

analysis, and (3) to implement automatic future M&R sequencing. 41

I-710 LONG BEACH REHABILITATION PROJECT (PHASE 1) 42

Interstate 710 (I-710), known as the Long Beach Freeway, opened in 1952 and serves as a major route for 43

commuter and commercial traffic between Los Angeles and Long Beach (Figure 1). It is also a gateway to 44

the Ports of Long Beach and Los Angeles, two of the busiest cargo ports in the U.S. However, a 51.5 km 45

stretch of the I-710 corridor had become seriously deteriorated and required rehabilitation to keep it safe 46

for road users. Caltrans consequently devised a rehabilitation project for I-710 and divided the plan into 47

four phases. To date, Phases 1 (2003) and 2 (2010) have been completed, while Phases 3 and 4 are 48

scheduled for the near future .Given the need for minimal disruption of heavy weekday traffic, Caltrans 49



decided to carry out the pavement rehabilitation on I-710 with 55-hour extended closures, Caltrans’ 1

typical Long-life Pavement Rehabilitation Strategy (LLPRS) practice for urban corridor networks. 2

3 FIGURE 1 Location of the California I-710 rehabilitation project (Phase 1: Long Beach). 4

The scope of the I-710 Long Beach Project (Phase 1) was to rehabilitate the approximately 4.4 5

centerline-km of existing concrete pavement on I-710 near the city of Long Beach with long-life (30-year 6

design) AC pavement. (Figure 2) (9). The existing pavement consisted of 200 mm (8 in.) portland cement 7

concrete (PCC) on top of 100 mm (4 in.) of cement-treated base (CTB), which was formerly Caltrans’ 8

most common rigid pavement type in the 1960s through 1970s. The rehabilitation included the three 9

main lanes, the median, and shoulder in each direction. Beneath the highway overpasses, which did not 10

meet current federal bridge clearance requirements, the existing concrete pavement structure was 11

removed—with an additional 150 mm (6 in.) excavation—and replaced with a total of 330 mm (13 in.) of 12

new AC with five layers. Between the overpasses, the old concrete slab was cracked, seated (rolled), and 13

overlaid with 230 mm (9 in.) of a new AC with four layers. Typically, two sections—a 400-m (1,300 feet) 14

section of full-depth asphalt concrete (FDAC) replacement under the overpass, and a 1,200-m (4,000 feet) 15

section of crack seat and overlay (CSOL) between the overpasses—were finished within one 55-hour 16

closure. 17



1

FIGURE 2 Long-life AC pavement rehabilitation on I-710 with 55-hour extended weekend closure. 2

Caltrans initially planned ten extended weekend closures with an incentive bonus, and the 3

contractor successfully completed the rehabilitation with eight closures and received a $500,000 incentive 4

bonus. 5

During the pavement rehabilitation with 55-hour extended weekend closures, Caltrans applied a 6

counter-flow traffic system, completely closing off one side of the highway for construction and diverting 7

traffic to the roadbed on the other side of the construction site through median crossovers. The outside 8

shoulder was temporarily converted to a main traffic lane to provide two lanes in each direction, using 9

moveable concrete barriers (MCB). The main rehabilitation operations were performed with around-the-10

clock construction (nonstop) during 55-hour extended weekend closures (from 10 p.m. Friday to 5 a.m. 11

Monday) to avoid weekday commute traffic. 12

A postconstruction summary report was recently published that included some periodic 13

measurements of long-life AC pavement performance on I-710 Long Beach (Phase 1), including those 14

made with the falling weight deflectometer (FWD) at approximate annual intervals as well as some 15

pavement noise and skid measurements, from the opening to traffic in the summer 2003 to January 2009 16

(10). In summary, the overall actual performance of the I-710 Long Beach Project measured for the last 17

five years shows the long-life AC pavement behaving as it was designed to do. In addition, the rutting 18

performance of the I-710 long-life AC pavement, which was measured in summer 2009 after six years of 19

service traffic, shows a very positive indication on rut depth: approximately 5 to 6 mm (about 2 inches) at 20

its greatest (roughly half of the expected long-life AC mix design criterion). 21

STUDY OBJECTIVE AND ANALYSIS PROCEDURES 22

The primary objective of the LCCA study summarized in the paper was validation of the benefit derived 23

by selecting long-life (for 30+ years design life) AC pavement 60 years of the analysis period. Following 24

the formal Caltrans LCCA procedure, agency costs (including initial construction cost and maintenance 25

cost) and road user costs (traffic delay) for the work zone are estimated for each alternative, utilizing 26

pavement engineering tools such as the RealCost and CA4PRS (Construction Analysis for Pavement 27



Rehabilitation Strategies). In this post-construction analysis, the baseline pavement type selected for the I-1

710 project (i.e., long-life AC pavement) is compared with other candidate alternative types from the 2

perspective of savings of life-cycle agency cost and user cost. 3

The Caltrans LCCA procedures summarized below—and as specified in the department’s procedure 4

manual (11)—have been applied to the validation of pavement type selection for the I-710 Long Beach 5

rehabilitation project. 6

Select several pavement design alternatives for initial construction, including pavement types, 7

cross-sections, materials, and expecting design lives. 8

Determine the analysis period to cover the design lives of the initial construction and future M&R 9

activities. Caltrans recommends using a 60-year analysis period when long-life (30+ years) 10

pavement design is compared in the LCCA. 11

Identify future M&R activities for each design alterative, including pavement cross-section 12

change, sequence, and timeline over the analysis period. 13

Analyze the construction schedule for the initial construction and the future M&R activities. 14

Estimate the project cost associated with the initial construction and the future M&R. 15

Calculate the road user cost (RUC) in the work zone for the initial construction and the future 16

M&R activities. 17

Calculate the life-cycle cost for each design alternative using the concept of net present value 18

(NPV) based on the discounted rate. 19

Evaluate the LCCA results for the pavement design alternatives in terms of the benefits of life-20

cycle cost savings to validate and justify the adoption of long-life AC pavement for the I-710 21

project 22

ENGINEERING TOOLS UTILIZED 23

CA4PRS for Schedule, Traffic, and Cost Analysis 24

This LCCA study utilized CA4PRS software to analyze the project schedule, construction cost, and road 25

user cost (12). This software was developed by the UC Berkeley Institute of Transportation Studies as an 26

FHWA pooled-fund program. CA4PRS incorporates three interactive analytical modules: a Schedule 27

module that estimates project duration, a Traffic module that quantifies the delay impact of work zone 28

lane closures, and a Cost module that compares project cost among alternatives (13). The results (outputs) 29

of these three modules in CA4PRS integrate directly into the formulation (inputs) of life-cycle cost 30

analysis. 31

These capabilities were confirmed on several large highway rehabilitation projects in U.S. states 32

including California, Minnesota, Utah, and Washington. For example, CA4PRS played a crucial role in 33

the concrete pavement reconstruction of Interstate 15 Devore near San Bernardino (California), helping 34

reduce agency cost by $8 million and saving $2 million in road user delays using continuous closures and 35

24/7 construction, compared with repeated (about 10 months) nighttime traffic closures, the traditional 36

approach (14). 37

There is growing recognition of the capabilities of CA4PRS and the benefits of its use. For 38

example, CA4PRS won a 2007 Global Road Achievement Award from the International Road Federation 39

(IRF). The FHWA recently endorsed CA4PRS as a ―2008 Priority, Market-Ready Technologies and 40

Innovations‖ product, and acquired an unlimited CA4PRS group license for all 50 states to deploy the 41

software nationally. The American Association of State Highway and Transportation Officials 42

(AASHTO) Technology Implementation Group (TIG) is focusing on CA4PRS for nationwide promotion 43

to its members. 44

RealCost for LCCA 45

RealCost software is a life-cycle cost analysis tool developed by FHWA to calculate life-cycle values for 46

both agency and user costs associated with the construction and rehabilitation of a highway project (7, 8). 47

The LCCA method in RealCost is computation intensive and ideally suited to a spreadsheet application. 48



However, the current version of RealCost (version 2.1) software does not have an analytical capacity to 1

calculate agency costs or to estimate service lives for individual construction or rehabilitation activities, 2

which should be input by users directly, based on agency’s practices. The software includes a function for 3

automating FHWA’s work zone user cost calculation method. This method for calculating user costs 4

compares traffic demand to roadway capacity on an hour-by-hour basis, revealing the resulting traffic 5

conditions. As with any economic tool, LCCA provides critical information to the overall decision-6

making process, but not the answer itself. 7

PAVEMENT DESIGN (TYPE) ALTERNATIVES 8

In interviews with the authors, I-710 project team members who participated in the design and 9

construction stages suggested the following three pavement design (type) alternatives for design 10

validation from a LCCA perspective: 11

Alternative 1—Innovative ACP rehabilitation: (a) Caltrans long-life crack, seat, and overlay 12

(CSOL) for total 2.8 centerline-km and (b) long-life full-depth asphalt concrete (FDAC) for total 13

1.6 centerline-km. 14

Alternative 2—Standard ACP rehabilitation: (a) standard-life CSOL for total 2.8 centerline-km 15

and (b) standard-life FDAC for total 1.6 centerline-km 16

Alternative 3—Long-life PCCP reconstruction for 4.4. centerline-km 17

Based on the interviews and the Caltrans LCCA procedure manual (11), more design details such 18

as cross-section, design life, and M&R sequence for each alternative were developed and confirmed by 19

pavement experts in industry (especially, the southern California chapter of the National Asphalt 20

Pavement Association (NAPA) and academia (University of California, Berkeley and Davis). 21

Alternative 1: Innovative Asphalt Concrete Pavement (ACP) 22

The Innovative ACP alternative, which is the long-life AC pavement implemented on the I-710 project, is 23

a new Caltrans AC pavement technology to enhance pavement quality and life (30-plus design years). It 24

consists of two rehabilitation sections (2.8 km total) with CSOL of existing PCC slabs with AC and three 25

FDAC replacement sections (1.6 km total) under highway overpasses. The designs for the innovative 26

pavement structure were developed using mechanistic-empirical (ME) design methodologies to 27

accommodate 200 million equivalent single axle loads (ESAL) over 30 years. The I-710 Long Beach 28

project was the first demonstration of the innovative ACP in the Caltrans Long-Life Pavement 29

Rehabilitation Strategies (LLPRS) program. The LLPRS was launched in 1998 to rebuild approximately 30

2,800 lane kilometers of deteriorated urban highways that had poor pavement structure condition and ride 31

quality with a minimum ADT of 150,000 or average daily truck traffic of 15,000 (9). The contract 32

included performance-related materials specifications for stiffness, fatigue resistance, and rutting 33

resistance for the AC layers, as well as for higher than normal compaction. 34

The long-life CSOL consists of 30 mm (1.2 in.) open-graded friction coarse (OGFC), 75 mm (2.9 35

in.) PBA-6a, 100 mm (3.9 in.) AR-8000, and 30 mm (1.2 in.) dense-graded asphalt concrete (DGAC) 36

(Figure 3[a]). 640 mm (25.2 in.) of the existing PCC pavement is excavated and 150 mm (5.9 in.) of 37

Aggregate Base (AB) is filled first in on the FDAC sections. The long-life FDAC consists of 30 mm (1.2 38

in.) of OGFC, 75 mm of PBA-6a, 150 mm of AR-8000, and 75 mm AR-8000(+0.5 percent) (Figure 3[b]). 39

The AR-8000 is an asphalt type having a viscosity of 8,000 poise (±25 percent) at 60°C after aging and 40

the AR-8000(+0.5 percent) is a rich bottom dense-graded asphalt concrete with conventional binder. The 41

PBA-6a is a dense-graded asphalt concrete type with polymer-modified binder. 42



1 FIGURE 3 Cross-sections of the innovative and standard ACP alternatives 2

Alternative 2: Standard Asphalt Concrete Pavement (ACP) 3

The Standard ACP alternative is based on a typical AC pavement cross-section for standard design life 4

(20 years), which is the most common flexible pavement design in California highways. The Caltrans 5

project team confirmed that if the Innovative ACP was not proposed, then most likely the Standard ACP 6

alternative could have been implemented to rehabilitate the existing PCC pavement on I-710 Long Beach. 7

The Standard ACP alternative consists of two sections (2.8 km total) with the standard-life CSOL of 8

existing PCC slabs with AC and three standard-life FDAC replacement sections (1.6 km total) under 9

highway overpasses. For the initial construction of the Standard ACP alternative, the standard CSOL 10

consists of 30 mm OGFC and 110 mm DGAC (Figure 3[c]). For the standard FDAC pavement section, 11

150 mm of the 730 mm of the existing pavement is excavated and filled with Aggregate Base (AB). The 12

standard FDAC pavement consists of 30 mm of OGFC and 550 mm of Aged Residue (AR)-4000 on top 13

of the 150 mm of new AB (Figure 3[d]). The AR-4000 is an asphalt type that has a viscosity of 4,000 14

poise (±25 percent) at 60°C after aging. 15

Alternative 3: Long-Life Portland Cement Concrete Pavement (PCCP) 16

Long-life PCCP competed with the Innovative ACP for use in replacing the entire stretch (total 4.2 17

centerline-km) of the I-710 Long Beach project. The Long-life PCCP consists of 300 mm Portland 18

concrete cement and 150 mm of hot-mix asphalt (HMA) or lean concrete base (LCB). Generally, Long-19

life PCCP requires a slightly higher initial construction cost than the long-life ACP but its use may result 20

in lower overall maintenance and user cost in life-cycle because it does not demand frequent maintenance 21

for overlays. 22

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LCCA COMPONENTS 1

The elements required to perform an LCCA for the I-710 project (Phase 1) include pavement design 2

alternatives, analysis period, discount rate, M&R schedules, and cost estimates. Per Caltrans policy (11), 3

this LCCA is based on a 60-year analysis period and applied a fixed discount rate of four percent, the 4

difference of between a six percent inflation rate and a two percent rate of interest in the long-run. No 5

salvage (or residual) value was accounted for in the sixtieth year and the cost of pavement treatment in the 6

sixtieth year was excluded for all the alternatives. The following sections describe the major elements and 7

their inputs and assumptions in this study. 8

Agency Cost Estimate 9

Construction cost for California highway projects consists of pavement cost, traffic-handling cost, 10

drainage cost, specialty (storm water pollution prevention plan: SWPPP) cost, and other miscellaneous 11

costs. In the CA4PRS cost module, pavement cost is estimated by a function (multiplication) of pavement 12

item, thickness, lane width, length, and unit price. The unit prices for major pavement items were 13

acquired from Caltrans’ contractor bid database (15). For the purpose of simplicity, other cost 14

components such as non-pavement items and indirect costs, and Caltrans engineering support costs were 15

covered by using multipliers, based on Caltrans typical cost estimate practice for rehabilitation projects, 16

as listed in Table 1. 17

TABLE 1 Typical Percentages and Multipliers of Cost Estimates 18

Number Construction Item(1)

Description Percentage Multiplier

1 Pavement Cost - 100% 1.00

2 Traffic Handling Cost % of (1) 8% 1.08

3 Drainage Cost % of (1) 1% 1.09

4 Specialty (SWPPP) Cost % of (1) 15% 1.24

5 Minor Cost % of Sum (1) through (4) 5% 1.30

6 Mobilization Cost % of Sum (1) through (5) 10% 1.43

7 Supplemental Cost % of Sum (1) through (6) 5% 1.50

8 Contingency Cost % of Sum (1) through (7) 20% 1.80

9 Engineering Supporting Cost % of Sum (1) through (8) 16% 2.09

Note: (1) Construction items are specified in the Caltrans Construction Manual, Chapter 4.Construction 19

details (16). 20

For example, the routine annualized maintenance cost used for the Standard FDAC and 21

Innovative FDAC and CSOL was $1,860 per kilometer ($3,000 per mile) and that used for the Standard 22

CSOL was $930 per kilometer ($1,500 per mile). The annual maintenance cost for the Long-life portland 23

cement concrete pavement (PCCP) was as $620 per kilometer ($1,000 per mile). Routine annualized 24

maintenance costs (dollar per lane-km per year) were acquired from the Caltrans LCCA procedure 25

manual (11). 26

Work Zone User Cost Calculation 27

The weekday traffic (146,000 average daily traffic [ADT]) and weekend traffic (106,000 ADT) were 28

collected before the construction (rehabilitation) and used in the work zone traffic analysis for LCCA. 29

Five percent of the traffic was assumed to be single unit trucks and ten percent a combination of trucks. 30



The annual growth rate of traffic volume was assumed at 0.5 percent every year (based on the California 1

historical traffic database) (17). 2

A two-peak pattern, a typical pattern on urban highway segments, was observed in the both 3

directions for the weekdays. Traffic during weekends was lower than traffic on weekdays for both 4

directions, appearing flat-peaked in afternoon. In Fact, Caltrans decided to undertake the project with the 5

55-hour extended weekend closures that least impact traffic, based on this traffic pattern. 6

In estimating road user cost with the CA4PRS Traffic module, which is based on the Highway 7

Capacity Manual’s demand-capacity model (18), traffic delay is given a road users’ time value that 8

includes additional travel time needed to pass through a work zone and extra time to travel through 9

detours required disruptions caused by construction activities that interfere with traffic flow. Traffic delay 10

is converted into a dollar amount using the value of time and it is compared among alternative as agency 11

cost was compared. The time value of passenger cars was $11.51 per hour and the time value of trucks 12

was $27.83 per hour, following Caltrans policy (19). 13

LCCA COMPARISON 14

Future Maintenance and Rehabilitation 15

For each pavement design alternative, future M&R details, such as sequencing, time frequency (design 16

life), and cross-sections, are developed based on the Caltrans LCCA Procedure Manual (11), as 17

summarized in Table 2. 18

Agency Costs Comparison 19

The agency cost of each construction activity for each alternative was also estimated using the CA4PRS 20

Cost module, which incorporates unit prices of major pavement items based on the Caltrans historical 21

contractor bid database (15). The agency’s initial construction (rehabilitation) cost for the Innovative 22

ACP (Alternative 1) was estimated at approximately $23.9 million and the initial construction cost of the 23

Standard ACP (Alternative 2) was estimated at $24.2 million. The agency’s initial construction cost for 24

the Long-life PCCP (Alternative 3, $63.5 million) was 270 percent higher than that of the Innovative 25

ACP. 26

The primary reason for the higher cost (about $63.5 million) of initial construction for the long-27

life PCCP, compared to that of the long-life ACP (about $23.9 million), is that the concrete mix is 28

assumed to be Rapid Strength Concrete (RSC), which cures within 12 hours from its mixing during 55-29

hour weekend closures. For comparison, if normal (28-day curing time mix) PCC is used, the initial 30

construction cost might be about half of the RSC cost. 31

Per the LCCA procedure, future M&R construction costs are discounted (with four percent) for 32

the net present value (NPV) conversion. After applying the discount rate, the discounted total NPV of life 33

cycle (60 years) agency cost (including the initial construction and future M&R) of the Innovative ACP 34

alternatives came to $31.2 million, as shown in Table 3 (i.e., about $17 million for CSOL and about $14 35

million for FDAC). 36

The total life-cycle agency cost of the Standard ACP is about $44 million, whereas the long-life 37

PCCP is about $70 million. The LCCA indicates that the Innovative ACP adopted on the I-710 Long 38

Beach project might save a total of about $13 million life-cycle agency cost over 60 years of the analysis 39

period (service life). 40

The LCCA results show that the Innovative ACP alternatives require the lowest agency cost for initial 41

construction as well as the lowest total agency cost for the entire life-cycle period among all the 42

alternatives. Compared with the long-life PCCP, the Innovative ACP saves a total of about $40 million 43

Caltrans capital project (agency cost). The LCCA study justifies the implementation of the long-life 44

(Innovative) ACP on the I-710 Long Beach project, from the total agency cost perspective in the long-run, 45

compared with other two alternatives. 46



TABLE 2 Summary of Schedule Estimates 1

Yr

Alt. 1: Innovative ACP Alt. 2: Standard ACP Alt. 3: Long-Life PCCP

a. CSOL b. FDAC a. CSOL b. FDAC

Description No. of

Closures Description No. of

Closures Description No. of

Closures Description No. of Closur

es Description

No. of Closures

0

30mm OGFC 75mm PBA-6a 100mm AR-8000 30mm DGAC

5 Week-

end

30mm OGFC 75mm PBA-6a 150mm AR-8000 OBC 75mm AR-8000+0.5%

5 Week-

end

30mm OGFC 75mm DGAC 30mm DGAC

6 Week-

end

30mm OGFC 550mm DGAC AR-4000

6 Week-

end

300mm PCC 150mm HMA or LCB

12 Week-

end

10

1st CAPM 1st CAPM n.a.

30mm Mill&Rep OGFC 30

Night 30mm Mill&Rep OGFC 17

Night

30mm Mill&Rep OGFC 60mm Mill DGAC 90mm Rep DGAC

70 Night

30mm Mill&Rep OGFC 60mm Mill&Fill DGAC

35 Night

15 n.a. n.a.

2nd CAPM n.a. 30mm Mill OGFC 30mm Mill&Rep DGAC 30mm Rep OGFC

45 Night n.a.

20

2nd CAPM 1st Rehab n.a.

30mm Mill&Rep OGFC 30 Night

30mm Mill&Rep OGFC

17 Night


90 Night

30mm Mill&RepOGFC 60mm Mill&Fill DGAC

35 Night

30

1st Rehab 2nd Rehab 1st CAPM 30mm Mill&Rep OGFC 75mm Mill&Fill PBA-6a

70 Night

30mm Mill&Rep OGFC 75mm Mill&Fill PBA-6a

45 Night


70 Night


35 Night CPR(C)

38 Night

35 n.a. n.a.

3rd CAPM 2nd CAPM 30mm Mill OGFC 30mm Mill&Rep DGAC 30mm Rep OGFC

45 Night n.a. CPR(B) 75

Night

40

3rd CAPM 3rd Rehab n.a.

30mm Mill&Rep OGFC 30 Night Mill&Rep OGFC 17

Night


90 Night


35 Night

45 n.a. n.a. n.a. n.a. 3rd CAPM

CPR(A) 130

Night

50

4th CAPM 4th CAPM 1st Rehab

30mm Mill&Rep OGFC 30

Night 30mm Mill&Rep OGFC 17

Night


70 Night


35 Night 300mm PCC

8 Week-

end

55 n.a. n.a.

5th CAPM n.a. 30mm Mill OGFC 30mm Mill&Rep DGAC 30mm Rep OGFC

45 Night n.a. -

Note: Weekend = 55-hour extended weekend closure (Friday 10 P.M – Monday 5 A.M. 2

Night = 8-hour night time closure (9 P.M.-5 A.M.) 3

4



1

TABLE 3 Summary of Life-Cycle Costs 2

Year

Alt 1: Innovative ACP Alt 2: Standard ACP Alt 3: Long-Life PCCP

a. CSOL b. FDAC a. CSOL b. FDAC

Agency Cost

RUC(1) Agency

Cost RUC(1)

Agency Cost

RUC(1) Agency

Cost RUC(1)

Agency Cost

RUC(1)

0 $12.23M $0.66M $11.62M $0.66M $6.71M $0.79M $17.49M $0.79M $63.45M $1.58M

10

$1.24M $0.77M $0.68M $0.44M $4.31M $1.80M $1.55M $0.93M

15 2nd CAPM

$1.91M $1.04M

20 2nd CAPM 1st Rehab

$0.84M $0.60M $0.46M $0.36M $3.63M $1.78M $1.05M $0.71M

30 1st Rehab 2nd Rehab 1st CAPM

$2.03M $1.06M $1.11M $0.70M $1.97M $1.06M $0.71M $0.55M $0.32M $0.58M

35 3rd CAPM 2nd CAPM

$0.87M $0.61M $1.24M $1.00M

40 3rd CAPM 3 rd Rehab

$0.38M $0.35M $0.21M $0.21M $1.66M $1.03M $0.48M $0.41M

45 3rd CAPM

$1.20M $1.30M

50 4th CAPM 4th CAPM 1st Rehab

$0.26M $0.26M $0.14M $0.16M $0.90M $0.61M $0.32M $0.31M $3.38M $0.70M

55 5th CAPM

$0.40M $0.35M

60

Sub-Total

$16.97M $3.70M $14.23M $2.52M $22.35M $9.08M $21.59M $3.70M $69.59M $5.16M

Total Life-cycle Cost

$31.20M (Agency Cost) + $6.25M (RUC) =$37.42M

$43.94M (Agency Cost)+$12,78M (RUC) = $56.68M

$69.59M(Agency Cost) +$5.16M(RUC)

=$74.75M

Note: (1) RUC = Road user cost. 3

(2) Costs in the table are discounted (with four percent rate) net present value (NPV). 4

Agency costs also include the annualized routine maintenance costs (dollar per lane-km per year), 5

which is a relatively small dollar amount, compared with the initial and major M&R costs, based on the 6

Caltrans LCCA Procedure Manual (11). For the routine annualized maintenance life-cycle cost of the 7

Innovative ACP alternative, the CSOL section requires $1.07 million in total and the FDAC section 8

requires $0.59 million in total for the 60 years of the LCCA period in NPV. For the Standard alternative, 9

the CSOL section requires $0.54 million in total and the FDAC section requires $0.59 million in 10

annualized routine maintenance cost (NPV) for the LCCA period. The Long-life PCCP alternative only 11

requires $0.55 million in annualized routine maintenance costs for the 40 lane-km (24.5 lane-mi.) of the 12

PCC section. 13



Construction Schedule Comparison 1

Construction schedule (mainly closure number) is a needed parameter for the LCCA to be inputs for cost 2

estimates (especially transportation management plan cost and more importantly work zone traffic delay 3

cost analysis. 4

Utilizing CA4PRS software, the construction schedules for initial rehabilitation and future M&R 5

were determined for each alternative, as summarized in Table 2. According to the scheduling results, 6

Alternatives 1 (the Innovative ACP alternatives) require total ten (five for CSOL and five for FDAC) 55-7

hour extended weekend closures and Alternatives 2 (the Standard ACP alternatives) require twelve (six 8

for CSOL and six for FDAC) 55-hour extended weekend closures, whereas Alternative 3 (the Long-life 9

PCCP alternative) requires twelve weekend closures for the initial construction. Comparing the schedules 10

for the entire life-cycle analysis period (60 years), the Innovative ACP (Alternative 1) requires about total 11

190 nighttime closures for the CSOL sections and about total 113 nighttime closures for the FDAC 12

sections for their future maintenance. The Standard ACP (Alternative 2) requires about total 525 13

nighttime closures for the CSOL sections and about total 175 nighttime closures of the FDAC sections for 14

their maintenance. The Long-life PCCP (Alternative 3) requires another eight weekend closures 50 years 15

after initial construction, in addition to total 243 nighttime closures for future M&R, and five weekend 16

closures for its rehabilitation (slab replacement at year 35) (Table 2). 17

User Costs Comparison 18

Road user cost is generated by additional traffic delays due to lane closures during construction. This cost 19

is considered as an indirect public inconvenience (time value) cost through work zone rather than an 20

agency cost (real money) but it comes to the fore when included in an LCCA. This study utilized 21

CA4PRS’traffic module. The work zone traffic analysis results show no significant difference between the 22

user costs of the Innovative ACP (Alternative 1, $1.32 million) and the Standard ACP (Alternative 2, 23

$1.58 million) for the initial construction. However NPV of total life cycle user cost of the Standard ACP 24

alternative ($12.78 million) is almost twice as high as that of the Innovative ACP alternative ($6.22 25

million) for the entire life-cycle analysis period (Table 3). The user cost of the Long-life PCCP is 26

estimated to be as much as $5.16 million, which is less than that of the Innovative ACP alternative. 27

SUMMARY AND CONCLUSIONS 28

LCCA for highway projects is an analytical technique that uses economic principles in order to evaluate 29

long-term alternative investment options, especially for comparing the value of alternative pavement 30

structures and strategies. 31

Life-cycle costs including agency and user costs, for three different pavement design alternatives 32

(i.e., Innovative (long-life) ACP, Standard (-life) ACP, and Long-life PCCP) were compared with the 33

software (CA4PRS and RealCost). The LCCA utilized in the study followed the Caltrans procedure and 34

policy and incorporated filed information especially the project team’s expert opinions, collected through 35

post-construction interviews. Based on this information, LCCA inputs such as pavement cross-sections 36

and materials, future M&R sequencing and timeline, and lane closure schemes were generated to compare 37

the three pavement design alternatives. 38

Construction schedule for initial construction and subsequent future M&R activities for each of 39

the alternatives were determined in the CA4PRS schedule module. Agency costs were estimated based on 40

material unit prices, which incorporate the Caltrans historic bid database, and pavement quantity in the 41

CA4PRS cost module. User costs in the work-zones for each activity were quantified in the CA4PRS 42

traffic module. The concept of NPV is used for life cycle cost summary and conversion with four percent 43

discount rate. 44

Comparison of the total agency and user life-cycle costs for the alternatives indicated that the 45

Innovative (long-life) ACP alternative ($39.1 million), which was actually implemented on the I-710 46

Long Beach rehabilitation project, had the lowest costs over 60 years of the analysis period. The total life-47

cycle cost of the Standard ACP alternative was $57.2 million and that of the Long-Life PCCP Alternative 48



was $75.3 million (Figure 4). In summary, this LCCA case study proves that the I-710 rehabilitation 1

project implemented the most life-cycle cost effective pavement design type (Innovative long-life ACP) 2

that might save a total agency and user life cycle cost of $18 million, compared to the Standard ACP 3

alternative, and about $36 million, compared to the Long-life PCCP alternative, in the long-run (60 years 4

of the analysis period). More specifically, the life-cycle agency cost for the Innovative ACP alternative 5

($31.2 million) is about $13 million more cost-effective than that of the Standard ACP alternative ($44 6

million) and is about $38 million cheaper than the Long-life PCCP alternative ($69.6 million). 7

This post-construction LCCA case study not only supports and justifies the adoption of the 8

innovative pavement technology on the I-710 Long Beach project, but it also emphasizes the importance 9

of LCCA implementation for pavement (design) type comparison for highway rehabilitation projects. 10

11

FIGURE 4 Comparison of total life-cycle costs (NPV) for the alternatives. 12

It is recommended that transportation agencies undertake an appropriate LCCA during the 13

pavement design and planning stages. Furthermore, utilization of construction analysis tools such as 14

CA4PRS or RealCost will present comprehensive and realistic LCCA results, minimizing engineers’ 15

efforts and uncertainty. 16

ACKNOWLEDGEMENTS 17

The contents of this paper reflect the views of the authors and are not the official views of the State of 18

California. The authors thank Caltrans engineers (especially, Bill Nokes) and other pavement experts 19

(Prof. Carl Monismith and Louw Plessis) who participated in the interview and survey. 20



REFERENCES 1

1. California Department of Transportation (Caltrans). Life-Cycle Cost Analysis, Office of Pavement 2

Engineering, Sacramento, CA, 2007. http://www.dot.ca.gov/hq/esc/Translab /ope/LCCA.html. 3

Accessed June 25, 2009. 4

2. California Department of Transportation (Caltrans). Highway Design Manual, Sacramento, CA, 2007. 5

http://www.dot.ca.gov/hq/oppd/hdm/hdmtoc.htm. Accessed on June 5, 2009. 6

3. Papagiannakis, P. and M. Delwar. Computer Model for Life-Cycle Cost Analysis of Roadway 7

Pavements. Journal of Computing in Civil Engineering, ASCE, Vol. 15 (2), 2001, pp. 152-156. 8

4. Salem, O., S. AbouRizk, and S. Ariaratnam. Risk-based Life-cycle Costing of Infrastructure 9

Rehabilitation and Construction Alternatives. Journal of Infrastructure Systems, ASCE, Vol. 9, No. 1, 10

2003, pp. 6-15. 11

5. Gransberg, D.D. and K.R. Molenaar. Life-Cycle Cost Award Algorithms for Design/Build Highway 12

Pavement Projects. Journal of Infrastructure Systems, ASCE, Vol. 10, No. 4, 2004, pp. 167-175. 13

6. Labi, S. and K.C. Sinha. Life-Cycle Evaluation of Flexible Pavement Preventive Maintenance. 14

Journal of Transportation Engineering, ASCE, Vol. 131 No. 10, 2005, pp. 744-751. 15

7. U.S. Department of Transportation. Life-Cycle Cost Analysis Primer. Federal Highway 16

Administration, Office of Asset Management, 2002. isddc.dot.gov/OLPFiles/FHWA/010621.pdf. 17

Accessed June 1, 2010. 18

8. U.S. Department of Transportation. Life-Cycle Cost Analysis RealCost User Manual. Federal 19

Highway Administration, Office of Asset Management, 2004. 20

www.fhwa.dot.gov/infrastructure/asstmgmt/rc210704.pdf. Accessed June 1, 2010. 21

9. Lee, E.B., H. Lee, and M. Akbarian. Accelerated Pavement Rehabilitation and Reconstruction with 22

Long-Life Asphalt Concrete on High-Traffic Urban Highways. Journal of the Transportation 23

Research Board, No 1905, Transportation Research Board of the National Academies, Washington, 24

D.C., 2005, pp. 56-64. 25

10. Monismith, C.L., J.T. Harvey, B. Tsai, F. Long, and J. Signore. Summary Report: The Phase 1 I-710 26

Freeway Rehabilitation Project: Initial Design (1999) to Performance after Five Years of Traffic 27

(2009). Report No: UCPRC-SR-2008-04 (FHWA No.: CA101891A), February 2009. 28

11. California Department of Transportation. Life-Cycle Cost Analysis Procedures Manual, 2007. 29

www.dot.ca.gov/hq/esc/Translab/OPD/LCCA_Manual_MASTERFinal.pdf. Accessed June 1, 2010. 30

12. Lee, E.B. and C.W. Ibbs. Computer Simulation Model: Construction Analysis for Pavement 31

Rehabilitation Strategies. Journal of Construction Engineering and Management, Vol. 131 No. 4, 32

2005, pp. 449-458. 33

13. Lee, E.B., and K. Choi. Pavement Rehabilitation: Fast-Track Construction for Concrete Pavement 34

Rehabilitation: California Urban Highway Network. Journal of the Transportation Research Board, 35

No 1949, Transportation Research Board of the National Academies, Washington, D.C., 2006, pp. 3-36

10. 37

14. Lee, E.B., and D.K. Thomas. State-of-Practice Technologies on Accelerated Urban Highway 38

Rehabilitation: I-15 California Experience. Journal of Construction Engineering and Management, 39

Vol. 133, No. 2, 2007, pp.105-113. 40

15. California Department of Transportation. Caltrans Contractor Bid Database, 2010. 41

sv08data.dot.gov.ca/contractcost. Accessed July 1, 2010. 42

16. California Department of Transportation. Caltrans Construction Manual, 2009. 43

http://www.dot.ca.gov/hq/construc/manual2001/. Accessed July 1, 2010. 44

17. California Department of Transportation. Caltrans Traffic Data Branch. traffic-45

counts.dot.ca.gov/index.htm. Accessed July 1, 2010 46

18. Transportation Research Board, Highway Capacity Manual 2000, National Research Council, 47

Washington D.C. 2000. 48

19. California Department of Transportation. 2006 Travel Time Values for Automobiles and Trucks, 49

Division of Traffic Operations, Memorandum. March 3, 2006. 50


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