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Evaluation of Ultra-High Performance Concrete Connections (2022)

Chapter: Section 6 - Quantification of Socioeconomic Impacts

« Previous: Section 5 - Business Case for and Barriers to Adoption of UHPC-C
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Suggested Citation:"Section 6 - Quantification of Socioeconomic Impacts." National Academies of Sciences, Engineering, and Medicine. 2022. Evaluation of Ultra-High Performance Concrete Connections. Washington, DC: The National Academies Press. doi: 10.17226/26634.
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SECTION 6

Quantification of Socioeconomic Impacts

Figure 6-1 depicts the logic model of the influence of TFHRC inputs on UHPC-C adoption and impacts. TFHRC contributed staff hours, strategy, and facilities to supporting UHPC-C adoption. These inputs have been used to characterize materials; test, validate, and demonstrate structural properties; and provide information for bridge design and construction using UHPC. As described in Section 4, the outputs of these activities are

  • Open-source materials characterization data,
  • Computational models for estimating structural performance,
  • Component-testing results,
  • A publicly available database of UHPC deployments in the United States and Canada,
  • Technical briefs and publications outlining design guidelines and other research results,
  • Outreach programs and direct consultation with owners and industry.

The hypothesis of this evaluation was that the main outcome of TFHRC activities and outputs is the increased adoption of UHPC-C, contributing to the increased adoption of PBE deck slabs (mostly for ABC applications) among U.S. owners and industry. This means that the adoption of PBE decks with UHPC-C will advance from demonstration projects to expanded deployment among more states. Because of the barriers to adoption described in Section 5, it may be some time before the use of PBE deck slabs becomes standard practice among owners and industry. However, UHPC-C use is increasingly becoming standard practice whenever PBE deck slabs are implemented.

UHPC-C improves bridge performance by decreasing maintenance and increasing life expectancy, reducing the need for future construction. The use of PBEs also decreases field construction time, decreasing travel disruptions, reducing emissions, and increasing safety. By helping support PBE adoption, UHPC-C accounts for a portion of the associated PBE benefits.

6.1 Quantification Methods

This section details the evaluation’s methods for estimating the socioeconomic impacts of UHPC-C adoption. The quantification process included four stages, depicted in Figure 6-2:

  1. Estimate the impact metrics for a single deployment of UHPC-C.
  2. Scale the individualized impact metrics to a national level.
  3. Estimate the benefits attributable to TFHRC UHPC-C research.
  4. Compare those attributed benefits with the costs of TFHRC UHPC-C research to generate a public benefit–cost ratio (BCR) and net present value (NPV).

The methods for completing each stage are described in the following subsections.

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Suggested Citation:"Section 6 - Quantification of Socioeconomic Impacts." National Academies of Sciences, Engineering, and Medicine. 2022. Evaluation of Ultra-High Performance Concrete Connections. Washington, DC: The National Academies Press. doi: 10.17226/26634.
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NOTE: PBE = prefabricated bridge element; TFHRC = FHWA Turner-Fairbank Highway Research Center; UHPC = ultra-high performance concrete; UHPC-C = UHPC connections.

Figure 6-1. Logic model for TFHRC influence on adoption of UHPC-C.
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Suggested Citation:"Section 6 - Quantification of Socioeconomic Impacts." National Academies of Sciences, Engineering, and Medicine. 2022. Evaluation of Ultra-High Performance Concrete Connections. Washington, DC: The National Academies Press. doi: 10.17226/26634.
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NOTE: ABC = accelerated bridge construction; BCR = benefit–cost ratio; NPV = net present value; TFHRC = FHWA Turner-Fairbank Highway Research Center; UHPC-C = ultra-high performance concrete connections.

Figure 6-2. Method for quantifying socioeconomic impact of UHPC-C.

6.2 Estimate Impact Metrics

The evaluation started by estimating the marginal benefits and costs associated with adopting UHPC-C compared with CC-C for a typical ABC bridge project. The difference between benefits and costs is the net benefits associated with adoption. Net benefits were expressed in dollars per project and then scaled to the estimated number of bridge projects in the United States to estimate national benefits.

Net benefits of UHPC-C depend on the attributes of each bridge implementation project. As discussed in Section 5, interviews indicated that the benefits of using PBE bridge decks with UHPC-C vary by project characteristics, including traffic, climate, and whether the bridge crosses water. To reflect diversity among different projects, net benefits estimates were developed for three benefits levels—low, medium, and high—on the basis of these project characteristics. TFHRC data on the number and type of UHPC-C implementations were then used to scale the net benefits to a national level.

6.2.1 Costs

The main added cost of using UHPC rather than conventional concrete is the cost of materials, although there are some added operational costs.

Materials Costs

Although UHPC is stronger and more durable than concrete, it is much more expensive. Regular field-cast concrete costs about $90/yd3, while UHPC costs about $2,000/yd3, which includes the materials costs; mixing costs; and the costs of quality control, packing, and delivery on site. LafargeHolcim produces Ductal, a proprietary blend of UHPC that was patent protected until 2019 and, therefore, has been used in almost all structural applications of UHPC in the United States. As of the writing of this report, at least three other competing companies are producing proprietary UHPC blends in the United States. Proprietary patents have likely contributed to historically high UHPC prices, although the increased market competition may help bring prices down.

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Suggested Citation:"Section 6 - Quantification of Socioeconomic Impacts." National Academies of Sciences, Engineering, and Medicine. 2022. Evaluation of Ultra-High Performance Concrete Connections. Washington, DC: The National Academies Press. doi: 10.17226/26634.
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After the patent for Ductal expired and TFHRC produced the report Development of Non-Proprietary Ultra-High Performance Concrete for Use in the Highway Bridge Sector (Graybeal 2013), several state DOTs, including Arizona’s (ADOTRC 2019) and Montana’s (Berry, Snidarich, and Wood 2017), began to develop generic UHPC options. Although generic UHPC options could lower prices further, they may also increase liability for users if they are less proven or less widely adopted than better-established and more trusted brands.

Availability of steel reinforcement fibers can also drive the high cost of UHPC. A study on generic UHPC development has shown that the materials costs for UHPC range from $360/yd3 to $500/yd3 without steel reinforcement fibers, and the addition of steel reinforcement fibers costs $470/yd3 (Berry, Snidarich, and Wood 2017). The Buy American Act limits the steel producers that concrete producers can use. Furthermore, the volume of steel fiber needed for the UHPC market is small compared with other steel uses throughout the country, so U.S. steel companies do not have a strong business incentive to produce them. The use of alternative materials for reinforcement fibers, if feasible, could alleviate this problem.

Operational Costs

A possible limitation to use of UHPC is the time and equipment needed for mixing. Although UHPC can be mixed in most conventional mixers, it requires a longer mixing time and is generally done in a high-shear mixer because it requires less water than conventional concrete. (High-shear mixers are more expensive than their conventional counterparts and are not necessary for conventional concrete.) Some proprietary companies also require that users rent the companies’ mixers, adding both cost and time to construction.

Furthermore, UHPC is usually batched by mixing the powder components, gradually adding water and high-range water-reducing admixture until it becomes fluid, then adding the reinforcement fibers slowly to prevent clumping. This process can take more than 15 minutes and requires more labor than conventional concrete, which can be mixed at the batch plant in about 30 seconds. This time factor may be a significant hurdle during periods of high activity when plants need to produce large amounts of concrete for many jobs. Then, because UHPC requires higher temperatures to cure promptly, procurement of external heating sources or construction delays caused by weather could generate additional costs.

There is a small need for increased training for UHPC-C use. Interviews indicated that switching from using CC-C to UHPC-C may require about 1 day of training. TFHRC is currently drafting codified design principles for UHPC use to ease adoption and decrease the need for designers to individually apply updated principles.

Cost Calculations

Bridge contractors incorporate both materials and operational costs into their bid prices. The FIU ABC Project Database (2021) contains bid packages detailing the bid prices and quantities of different types of field-cast concrete for several bridge projects. Table 6-1 shows the average prices of conventional concrete versus UHPC.

Although the current cost of UHPC use is high, only a small amount is needed for bridge connections, limiting the impact on bridge construction costs. Interviews indicated that substituting UHPC for conventional concrete in bridge connections might increase bridge construction costs by only 1% to 2%. Few projects in the FIU database include cost information, but the findings in Table 6-2 are consistent with the feedback derived from interviews.

Data from the FIU ABC Project Database (2021) indicate a 1% increase in immediate construction costs per square foot for ABC projects completed from 2011 to 2019 using UHPC-C,

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Suggested Citation:"Section 6 - Quantification of Socioeconomic Impacts." National Academies of Sciences, Engineering, and Medicine. 2022. Evaluation of Ultra-High Performance Concrete Connections. Washington, DC: The National Academies Press. doi: 10.17226/26634.
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Table 6-1. Concrete unit prices ($/cubic yard) from bridge projects.

Concrete Type Average Range
Conventional $2,240 $625–$5,500
UHPC $10,961 $9,450–$14,000

NOTE: Sample includes bridges built between 2011 and 2019. UHPC = ultra-high performance concrete.

SOURCE: Cost information is from the Florida International University ABC Project Database (2021).

Table 6-2. Bid cost per square foot for ABC bridge projects with and without UHPC-C, 2011–2019.

Cost Metric Average ($2021) Range ($2021)
Bid Cost per Square Foot $531 $151–$1,118
With UHPC-C (N = 3) $536 $434–$637
Without UHPC-C (N = 14) $530 $151–$1,118
Difference $6 na
% Difference 1% na

NOTE: Sample includes bridges built between 2011 and 2019. ABC = accelerated bridge construction; na = not applicable; UHPC-C = ultra-high performance concrete connections.

SOURCE: Cost information is from the Florida International University ABC Project Database (2021).

compared with those that did not use UHPC-C (Table 6-2). Furthermore, the cost of using UHPC-C is expected to decrease over time as contractors become more familiar with using the material. Impacts of UHPC-C on full life-cycle costs are considered in the following subsection on benefits.

6.2.2 Benefits

Table 6-3 shows the framework of benefits for UHPC-C. The quantitative analysis focuses on bridge performance benefits resulting from the use of UHPC-C and the benefits associated with increased adoption of ABC methods driven by UHPC-C. The hypothesis is that TFHRC research on and promotion of UHPC-C increased adoption, which in turn increased PBE adoption—predominantly for ABC methods—and the realization of associated benefits.3 The main benefits of PBE and ABC adoption are increased bridge performance and decreased construction time, each of which is discussed in the following subsections.

To consider broader socioeconomic returns, the analysis included not only the direct benefits of changes in construction time and bridge life expectancy, but also the indirect benefits of avoided congestion costs to individuals and commerce and potential health benefits from reduced vehicle emissions and fewer accidents for workers and drivers.

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3 UHPC-C can also be used for PBEs for non-ABC repairs or where field constraints limit on-site construction. Many substructures and barrier elements can also benefit from UHPC-C.

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Suggested Citation:"Section 6 - Quantification of Socioeconomic Impacts." National Academies of Sciences, Engineering, and Medicine. 2022. Evaluation of Ultra-High Performance Concrete Connections. Washington, DC: The National Academies Press. doi: 10.17226/26634.
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Table 6-3. Valuation metrics for TFHRC’s impact on UHPC use for bridge connections.

Broad Benefit (Qualitative) Specific Benefit (Qualitative) Benefitting Group Technical Impact Metric (Quantitative) Socioeconomic Value Metric (Monetized)
Increased Bridge Performance Increased bridge life expectancy General public; general contractors Reduced need for future construction (All benefits listed in this table) × (% reduction in future need for construction)
Increased Adoption of PBEs and ABC, Which Reduce Field Construction Time Reduced travel disruptions General publ ic Hours saved in public travel (Hours saved)×(valueof leisuretime)
Hours saved in commercial transport and business travel (Hours saved) × (value per hour)
Increased safety General publ ic Reduced vehicle emissions Value of reduced greenhouse gas emissions
Reduced traffic accidents in construction zones Value of avoided injury and death
General contractors Reduced construction worker accidents Value of avoided injury and death

NOTE = ABC = accelerated bridge construction; PBE = prefabricated bridge element; TFHRC = FHWA Turner-Fairbank Highway Research Center; UHPC = ultra-high performance concrete.

Increased Bridge Performance

The decreased permeability of UHPC increases its durability, increasing bridge life span. Decreased permeability reduces water and chloride migration, reducing UHPC’s exposure to damage from the freeze–thaw cycle and corrosion from chlorides. Less susceptibility to damage is important for superstructure components in northern areas that face adverse weather conditions and use salt on their roads, as well as for substructure components in bridges built in saltwater. Hence, although the initial cost of UHPC is far higher than conventional concrete, previous research has shown that its life-cycle costs may be lower.

For example, in the 2012 study Life Cycle Cost Analysis of a UHPC-Bridge on Example of Two Bridge Refurbishment Designs, S. Piotrowski and M. Schmidt conducted a life-cycle cost analysis of two replacement methods for the Eder River bridge in Felsberg, Germany (as discussed in Russell and Graybeal 2013). The first method used UHPC box girders filled with lightweight concrete, and the second used conventional prestressed concrete members. Using an annuity analysis, which estimates annual cost based on the NPV of the total construction and maintenance costs over a bridge’s life span, Piotrowski and Schmidt predicted that a UHPC bridge with a 100-year life span would cost about 15% less than a conventional concrete bridge with a 50-year life span (though UHPC had a higher initial cost). U.S. bridges are expected to meet design guides that specify a 75-year life span (Azizinamini et al. 2013). However, not all bridge deck components are expected to last that long, and bridge decks will likely have a shorter life span.

Reduced Field Construction Time

Despite some higher operational costs associated with using UHPC, UHPC-C could offer large socioeconomic benefits. By increasing bridge performance, UHPC-C reduce the need for future construction on rehabilitation and replacement. UHPC-C also support the adoption of ABC, which can drastically reduce the field time needed to construct bridges. Decreased field construction time reduces traffic disruptions, which generates time savings for commercial transport and the general public, increases safety by reducing the likelihood of traffic accidents, and reduces automobile emissions. Yet, ABC methods may or may not reduce bridge construction costs. Interviews and TRB expert panel feedback indicated that the costs of implementing

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Suggested Citation:"Section 6 - Quantification of Socioeconomic Impacts." National Academies of Sciences, Engineering, and Medicine. 2022. Evaluation of Ultra-High Performance Concrete Connections. Washington, DC: The National Academies Press. doi: 10.17226/26634.
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ABC in a new ecosystem are likely to be higher initially but decrease over time as local design, contracting, and concrete companies adapt their infrastructure and practices. For this reason, ABC bridge construction costs were assumed in this analysis to be the same as conventional construction.

Curing time to reach the early-age strength requirements to reopen roads is longer for UHPC than for conventional concrete. Ductal does offer accelerated cure mixes, but they may need higher-temperature curing conditions. Furthermore, the relationship between curing temperature and strength is closer in UHPC versus conventional concrete, so it is recommended that UHPC be cured at higher temperatures. This recommendation means that projects must either adjust construction schedules so that UHPC is cast in place during warmer weather or develop a curing scheme on site to artificially raise the curing temperature. These requirements can increase construction time for UHPC-C compared with CC-C. However, the UHPC performance factors that reduce construction time should outweigh the increased curing time and requirements.

Benefits Calculations

The lifetime benefits of using UHPC-C for an average ABC bridge construction project were calculated using Equation 1:

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First, the difference in life-cycle rehabilitation costs was measured for an ABC project using UHPC-C (ProjectAU) versus an ABC project using CC-C (ProjectAC). This step accounted for the direct performance benefits of UHPC (e.g., increased durability). Data from Kentucky and New York suggest that annual bridge rehabilitation costs are $11 to $19 per square foot (Table 6-4). The evaluation assumed that using UHPC-C reduces these costs by 10% to 20% on the basis of the bridge rehabilitation needs described by FHWA (2018c). This calculation estimated that using UHPC-C reduces annual bridge rehabilitation costs by $1 to $4 per square foot.

Next, the evaluation accounted for the benefits of ABC methods reasonably attributable to the availability of UHPC-C. The difference between a project using ABC methods with CC-C (ProjectAC) and a project using conventional construction methods with CC-C (ProjectCC) indicates the full benefits of using ABC methods over conventional construction methods without accounting for any direct performance benefits of using UHPC-C, as captured in the equation. The benefits of using ABC methods were then scaled down by the proportion of these benefits that can reasonably be attributed to the availability of UHPC-C.

Table 6-4. Reduced annual bridge rehabilitation cost from using UHPC-C, per square foot.

Low High
(1) Average annual bridge rehabilitation cost $11a $19b
(2) % reduction in rehabilitation cost from UHPC-C use 10% 20%
Reduced cost per year = (1) × (2) $1 $4

NOTE: UHPC-C = ultra-high performance concrete connections.

aValue updated to $2021 from Smith (2015).

bValue from New York State Office of the State Comptroller (2021).

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Suggested Citation:"Section 6 - Quantification of Socioeconomic Impacts." National Academies of Sciences, Engineering, and Medicine. 2022. Evaluation of Ultra-High Performance Concrete Connections. Washington, DC: The National Academies Press. doi: 10.17226/26634.
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Stakeholder interviews confirmed feedback elicited from the scoping interviews and the TRB expert panel—the availability of UHPC-C encouraged the adoption of ABC methods by providing connections at least as durable soon after placement as the PBEs they connect. Although conventional concrete has adequate compressive strength, UHPC’s better resistance to chloride infiltration should reduce premature cracking and material degradation in the connections. To estimate the value of this impact, the estimate of the benefits of implementing ABC methods (ProjectAC − ProjectCC) was multiplied by the extent to which UHPC-C are believed to have increased ABC adoption (UHPC IMPACT).

The main outcomes assessed for a given project are impacts related to the amount of time spent on construction. These impacts cover the benefits of avoided traffic congestion costs to individuals and commerce as well as the potential health benefits from reduced vehicle emissions and reduced risk of accidents for workers and drivers.

For this study, the monetary disincentives owner agencies sometimes attach to construction contracts were used as a lower-bound proxy for the value of traffic congestion. Such disincentives are stipulated by hour or by day to encourage contractors to complete construction on schedule. These disincentives reflect the owner agencies’ perception of the value of each added day of construction. FHWA provides guidance on setting these disincentives and recommends that they be “calculated on a project-by-project basis using established construction engineering inspection costs, State-related traffic control and maintenance costs, detour costs, and road user costs. Costs attributed to disruption of adjacent businesses should not be included” (FHWA 1989).

Given the restrictions on what can be included in disincentive calculations, FHWA disincentives are reasonable lower bounds for impacts. Along with excluding business impacts, owner disincentives exclude the value of reduced risk of traffic and worker accidents as well as the value of avoided emissions. The average disincentive value ascribed by owners can be multiplied by the average decrease in construction days reported from using ABC to calculate the value of construction time savings (Table 6-5).

The average value of construction time saved per square foot of bridge can be compared with the average added construction cost per square foot of bridge when using ABC methods.

Table 6-5. ABC construction day savings, costs, value, and net benefit.

Metric Average Min Max
(1) ABC construction day savings (N= 16)a 218 20 728
(2) Daily disincentive (N= 8)b $18,634 $4,451 $35,470
(3) Construction time savings value = (1) × (2) $4,062,212 $89,020 $25,822,160
(4) Construction time savings value per square foot $245 $5 $1,557
(5) ABC construction cost per square foot without UHPC-C (N = 8)c $531 $151 $1,118
(6) Ratio of ABC versus conventional construction costs 1.39 1.81 0.96
(7) Added ABC costs per square foot = (5) – ((5) / (6)) $149 $68 ($47)
(8) Net ABC construction benefits per square foot = (4) – (7) $96 ($62) $1,603

NOTE: Sample includes bridges built between 2011 and 2019. ABC = accelerated bridge construction; UHPC-C = ultra-high performance concrete connections.

aCalculated difference between reported days of construction and estimated days of conventional construction.

bMonetary penalties per day of construction beyond projected schedule. Imposed by owners on contractors.

c Sample reduced to non-UHPC-C ABC bridges with available estimates for conventional construction costs.

SOURCE: Cost information is from the Florida International University ABC Project Database (2021).

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Suggested Citation:"Section 6 - Quantification of Socioeconomic Impacts." National Academies of Sciences, Engineering, and Medicine. 2022. Evaluation of Ultra-High Performance Concrete Connections. Washington, DC: The National Academies Press. doi: 10.17226/26634.
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The added cost of ABC construction was provided by a sample of owners reporting information in the FIU ABC Project Database. The average estimated ratio of ABC versus conventional construction is 1.39 (with upper and lower bounds ranging widely from 0.96 to 1.81 because of the small sample size and early stage of technology adoption). That is, current bridge project data suggest that ABC methods cost on average 40% more than conventional methods. Although this cost difference appears large, the value of construction time savings suggested by contractual disincentives outweighs these costs. The average value of construction time savings is $245 per square foot, while the average added cost of ABC construction is $150 per square foot. Thus, the average net benefit of ABC construction is $95 per square foot.

The average net benefit of ABC construction was then scaled to reflect the proportion of these benefits reasonably attributable to UHPC-C. Interviews suggested that the main alternatives to UHPC-C are reinforced CC-C and grouted connections, that these alternatives perform significantly worse than UHPC-C, and that UHPC-C adoption rates will increase as familiarity with the material increases and costs decrease. Among the bridges covered in the FIU database, roughly 25% using PBE deck slabs relied on UHPC-C. The remainder relied on a combination of CC-C and grouted connections. The characterization of bridge construction methods in the NBI database is different than in the FIU database and FHWA UHPC bridge project records. Hence, accurately assessing the national proportion of PBE bridges using UHPC-C is difficult.

To keep estimates conservative, a range of 15% to 25% attribution of ABC time benefits was applied to UHPC-C use, which is likely a lower bound because UHPC-C adoption is expected to increase. Applying this range generates estimated net benefits of ABC bridge construction time savings attributable to the use of UHPC-C of $14 to $24 per square foot. Although these calculations are simple, there is good reason to believe that they elicit a lower-bound estimate of benefits: they are unlikely to fully reflect the value of reduced emissions and worker and traffic safety, and they are based on a conservative attribution of ABC construction time savings to UHPC-C use.

6.3 Scale to National Level

The onetime costs of using UHPC-C over CC-C ($6 per square foot of bridge) were subtracted from the onetime benefits of field construction time savings attributable to using ABC methods with UHPC-C ($14 to $24 per square foot). This generates onetime net benefits of UHPC-C of $8 to $18 per square foot of bridge. See Table 6-6 for a summary of UHPC-C net benefits. The annual performance benefits of UHPC-C use in reduced annual rehabilitation costs ($1 to $4 per square foot per year) can be aggregated over the evaluation period and added to the onetime net

Table 6-6. UHPC-C net benefits per square foot of bridge.

Metric Low High
Onetime UHPC-C net benefits $8 $18
= ABC field construction time savings attributable to UHPC-C use $14 $24
− UHPC-C construction costs $6 $6
Annual UHPC-C bridge performance benefits $1 $4

NOTE: ABC = accelerated bridge construction; UHPC-C = ultra-high performance concrete connections.

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Suggested Citation:"Section 6 - Quantification of Socioeconomic Impacts." National Academies of Sciences, Engineering, and Medicine. 2022. Evaluation of Ultra-High Performance Concrete Connections. Washington, DC: The National Academies Press. doi: 10.17226/26634.
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Table 6-7. UHPC-C for PBE deck slabs in the United States, by region and crossing feature.

Region Crossing Feature
Water Road Railroad
Northeast 65 65 3
Midwest 9 5 0
West 22 5 4
South 5 1 0

NOTE: PBE = prefabricated bridge element; UHPC-C = ultra-high performance concrete connections.

SOURCE: FHWA Turner-Fairbank Highway Research Center database of UHPC bridge applications.

Table 6-8. Present value of benefits for U.S. UHPC-C bridges built, 2011–2018.

Low High
PV of Benefits ($2021) $20,830,000 $56,284,000

NOTE: PV = present value; UHPC-C = ultra-high performance concrete connections.

benefit values. These onetime and annual benefits per square foot of bridge were then projected to a national level based on past and potential future U.S. deployments of UHPC-C.

6.3.1 Past UHPC Adoption

TFHRC maintains a database detailing all applications of UHPC to bridges throughout the United States, including the location, crossing feature, year constructed, owner agency, and component in which UHPC was used. These data allowed the evaluation to scale the estimated UHPC-C benefits per square foot of bridge to a national level on the basis of the aggregate square footage of past projects by year. Table 6-7 shows the counts of UHPC-C applications for PBE deck slabs by region and crossing feature from the TFHRC database. Most bridges using UHPC-C as of 2018 were constructed in regions with colder climates or over water. Interview results confirmed the same pattern of use and highlighted high traffic levels as an additional factor encouraging ABC use and thereby UHPC-C.

The calculated UHPC-C benefits per square foot of bridge displayed in Table 6-6 were applied to the aggregate square footage per year of the 185 bridges constructed using UHPC-C between 2011 and 2018, at a discount rate of 2.5%.4 This calculation generated a present value of realized UHPC-C benefits of $20.8 million to $56.3 million (Table 6-8).

6.3.2 Future Adoption Scenarios

The use of UHPC-C whenever ABC methods are employed has been standard practice in New York and Iowa for almost 10 years, and it is becoming standard practice in several other states such as Pennsylvania, New Jersey, and Idaho. However, as noted, overall adoption of PBEs and ABC methods has remained limited. Interviews indicated that adoption is likely to increase slowly until states take strong initiatives to facilitate industry adjustments away from

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4 A discount rate of 2.5% is recommended in Office of Management and Budget, Guidelines and Discount Rates for Benefit–Cost Analysis of Federal Programs, Appendix C, OMB Circular A-94, January 2003.

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Suggested Citation:"Section 6 - Quantification of Socioeconomic Impacts." National Academies of Sciences, Engineering, and Medicine. 2022. Evaluation of Ultra-High Performance Concrete Connections. Washington, DC: The National Academies Press. doi: 10.17226/26634.
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Image
NOTE: UHPC-C = ultra-high performance concrete connections.
SOURCE: FHWA, 2019b.

Figure 6-3. Number of U.S. bridges built per year using UHPC-C, 2011–2018.

steel and CC-C. In addition, the differential benefits associated with PBE and ABC adoption based on project characteristics are likely to lead to different levels of adoption. Between 2011 and 2018, UHPC-C use increased by an average of 53% per year (Figure 6-3). Although interviews suggested that UHPC-C adoption would continue to increase, an average future growth rate of 26% was assumed for this analysis, to remain conservative.

The evaluation generated a likely time series of the number and types of bridge projects that will adopt UHPC-C each year for the next 10 years. Potential bridge projects were identified using the NBI database, which rates overall bridge conditions as “poor,” “fair,” or “good.” Selecting the bridges rated “poor” returns about 45,000 bridges that could be replaced. This is consistent with the findings of ASCE’s 2017 Infrastructure Report Card, which concluded that more than 56,000 bridges carrying roads across the United States are structurally deficient.

The assumed 26% growth rate was applied to the observed percentage of bridges using UHPC-C from 2011 through 2018 to generate the percentage of bridges likely to use UHPC-C over the next 10 years. These projections were applied to the roughly 45,000 bridges rated in poor condition to estimate that approximately 750 bridges will be replaced using UHPC-C over the next 10 years. Table 6-9 shows the breakdown of potential UHPC-C bridge replacements by region and crossing feature.

Table 6-9. Potential UHPC-C bridge construction, by region and crossing feature, 2019–2028.

Region Crossing Feature
Water Road Railroad Other
Northeast 308 236 31 4
Midwest 40 9 0 0
West 89 8 12 1
South 15 1 0 0

NOTE: UHPC-C = ultra-high performance concrete connections.

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Suggested Citation:"Section 6 - Quantification of Socioeconomic Impacts." National Academies of Sciences, Engineering, and Medicine. 2022. Evaluation of Ultra-High Performance Concrete Connections. Washington, DC: The National Academies Press. doi: 10.17226/26634.
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Table 6-10. Present value of benefits for potential U.S. UHPC-C bridges, 2019–2028.

Low High
PV of benefits ($2021) $89,116,000 $249,589,000

NOTE: PV = present value; UHPC-C = ultra-high performance concrete connections.

The calculated UHPC-C benefits per square foot of bridge displayed in Table 6-6 were applied to the projected aggregate square footage of bridges that could be built using UHPC-C from 2019 through 2028 at a discount rate of 2.5%. This calculation generated a present value of future UHPC-C benefits of $89.1 million to $249.6 million (Table 6-10).

6.4 Estimate Benefits Attributable to TFHRC

The evaluation aggregated the estimated present value of realized and future benefits of using UHPC-C for past and likely future bridge projects throughout the United States, then attributed a portion of these benefits to TFHRC technology transfer efforts in the form of either research or dissemination. As mentioned in Section 4.3, interviewed stakeholders attributed most U.S. UHPC-C deployments to the efforts of TFHRC. Attribution was shared secondarily with proprietary UHPC suppliers that have conducted their own outreach activities and with university researchers. Stakeholders’ consistent responses on the high value and influence of TFHRC research and outreach suggest strong attribution, given that most respondents attributed virtually all U.S. UHPC-C deployments to TFHRC technology transfer efforts.

To keep estimates conservative, a range of 60% to 75% TFHRC attribution was applied to the estimated national-level UHPC-C benefits. The results, presented in Table 6-11, suggest a present value of realized and future UHPC-C benefits attributable to TFHRC of $66.0 million to $229.4 million.

6.5 Estimate Return on TFHRC Investment

As a final step in quantifying the impacts, the benefits of national-level UHPC-C use attributable to the TFHRC UHPC-C research program were compared with the costs associated with the research program. Integrating appropriated benefits and program costs yielded estimates of the return on public investment. Specifically, the BCR, NPV, and payback period were generated

Table 6-11. Present value of realized and potential UHPC-C benefits attributable to TFHRC, 2011–2028.

PV of Benefits ($2021) Low (60% Attribution) High (75% Attribution)
Realized $12,498,000 $42,213,000
Potential $53,470,000 $187,192,000
Total $65,968,000 $229,405,000

NOTE: PV = present value; TFHRC = FHWA Turner-Fairbank Highway Research Center; UHPC-C = ultra-high performance concrete connections.

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Suggested Citation:"Section 6 - Quantification of Socioeconomic Impacts." National Academies of Sciences, Engineering, and Medicine. 2022. Evaluation of Ultra-High Performance Concrete Connections. Washington, DC: The National Academies Press. doi: 10.17226/26634.
×

Table 6-12. Net present value and benefit–cost return of TFHRC UHPC-C research.

Low High
Realized Benefits (2011–2018) versus TFHRC Costs (2009–2017)
NPV ($2021) $9,391,000 $39,106,000
BCR 4.0 13.6
Realized and Potential Benefits (2011–2028) versus TFHRC Costs (2009–2017)
NPV ($2021) $62,861,000 $226,298,000
BCR 21.2 73.8

NOTE: BCR = benefit–cost ratio; NPV = net present value; TFHRC = FHWA Turner-Fairbank Highway Research Center; UHPC-C = ultra-high performance concrete connections.

for the research program. A BCR greater than 1 and an NPV greater than 0 each indicate positive returns, while the payback period indicates the years needed for accrued benefits to equal public investment.

TFHRC research specific to UHPC-C started in 2009 and largely concluded in 2017. The work was done in association with the Structures Lab and the Concrete Materials Lab. TFHRC’s estimate of the total expenditure specific to this topic is $2,545,000. Lab expenditures cover the costs of operating the labs: contract staff salaries, equipment, consumables, research specimens, and contractor travel to outreach events, for example, while federal staff time is instead covered by the FHWA general operating expenses budget. Assuming an even distribution of expenses over time and applying a 2.5% discount rate generates a present value of $3.1 million.

Table 6-12 provides a summary of the return-on-investment values for TFHRC UHPC-C research and dissemination activities. Even when comparing TFHRC UHPC-C research program costs with only the realized net benefits of UHPC-C attributable to TFHRC, the analysis suggests a realized NPV of $9.4 million to $39.1 million and a BCR of 4.0 to 13.6, meaning that for every dollar of TFHRC investments in UHPC-C research and dissemination, a minimum of $4.00 in national-level benefits was already realized between 2011 and 2018. Comparing TFHRC UHPC-C research program costs with the total realized and future net benefits of UHPC-C attributable to TFHRC suggests an NPV of $62.9 million to $226.3 million and a BCR of 21.2 to 73.8, meaning that for every dollar of TFHRC investments in UHPC-C research and dissemination, a minimum of $21.20 in national-level benefits will be realized between 2011 and 2028.

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Suggested Citation:"Section 6 - Quantification of Socioeconomic Impacts." National Academies of Sciences, Engineering, and Medicine. 2022. Evaluation of Ultra-High Performance Concrete Connections. Washington, DC: The National Academies Press. doi: 10.17226/26634.
×
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Suggested Citation:"Section 6 - Quantification of Socioeconomic Impacts." National Academies of Sciences, Engineering, and Medicine. 2022. Evaluation of Ultra-High Performance Concrete Connections. Washington, DC: The National Academies Press. doi: 10.17226/26634.
×
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Suggested Citation:"Section 6 - Quantification of Socioeconomic Impacts." National Academies of Sciences, Engineering, and Medicine. 2022. Evaluation of Ultra-High Performance Concrete Connections. Washington, DC: The National Academies Press. doi: 10.17226/26634.
×
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Suggested Citation:"Section 6 - Quantification of Socioeconomic Impacts." National Academies of Sciences, Engineering, and Medicine. 2022. Evaluation of Ultra-High Performance Concrete Connections. Washington, DC: The National Academies Press. doi: 10.17226/26634.
×
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Suggested Citation:"Section 6 - Quantification of Socioeconomic Impacts." National Academies of Sciences, Engineering, and Medicine. 2022. Evaluation of Ultra-High Performance Concrete Connections. Washington, DC: The National Academies Press. doi: 10.17226/26634.
×
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Suggested Citation:"Section 6 - Quantification of Socioeconomic Impacts." National Academies of Sciences, Engineering, and Medicine. 2022. Evaluation of Ultra-High Performance Concrete Connections. Washington, DC: The National Academies Press. doi: 10.17226/26634.
×
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Suggested Citation:"Section 6 - Quantification of Socioeconomic Impacts." National Academies of Sciences, Engineering, and Medicine. 2022. Evaluation of Ultra-High Performance Concrete Connections. Washington, DC: The National Academies Press. doi: 10.17226/26634.
×
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Suggested Citation:"Section 6 - Quantification of Socioeconomic Impacts." National Academies of Sciences, Engineering, and Medicine. 2022. Evaluation of Ultra-High Performance Concrete Connections. Washington, DC: The National Academies Press. doi: 10.17226/26634.
×
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Suggested Citation:"Section 6 - Quantification of Socioeconomic Impacts." National Academies of Sciences, Engineering, and Medicine. 2022. Evaluation of Ultra-High Performance Concrete Connections. Washington, DC: The National Academies Press. doi: 10.17226/26634.
×
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Suggested Citation:"Section 6 - Quantification of Socioeconomic Impacts." National Academies of Sciences, Engineering, and Medicine. 2022. Evaluation of Ultra-High Performance Concrete Connections. Washington, DC: The National Academies Press. doi: 10.17226/26634.
×
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Suggested Citation:"Section 6 - Quantification of Socioeconomic Impacts." National Academies of Sciences, Engineering, and Medicine. 2022. Evaluation of Ultra-High Performance Concrete Connections. Washington, DC: The National Academies Press. doi: 10.17226/26634.
×
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Suggested Citation:"Section 6 - Quantification of Socioeconomic Impacts." National Academies of Sciences, Engineering, and Medicine. 2022. Evaluation of Ultra-High Performance Concrete Connections. Washington, DC: The National Academies Press. doi: 10.17226/26634.
×
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Suggested Citation:"Section 6 - Quantification of Socioeconomic Impacts." National Academies of Sciences, Engineering, and Medicine. 2022. Evaluation of Ultra-High Performance Concrete Connections. Washington, DC: The National Academies Press. doi: 10.17226/26634.
×
Page 31
Next: Section 7 - Concluding Remarks »
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Beginning in 2019, the U.S. Federal Highway Administration (FHWA) requested that TRB be directly involved in managing evaluations of selected projects undertaken by the agency.

The TRB Cooperative Research Program's CRP Special Release 3: Evaluation of Ultra-High Performance Concrete Connections presents an evaluation of the UHPC Research and Development Program. UHPC is used in highway bridges, particularly for bridge-deck-level connections for prefabricated bridge elements.

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