SECTION 5

Evaluation of the Business Case and Barriers to Adoption

Interviews with SMEs suggest that the most promising use case for the ABQT is as a screening tool for quick tests on samples that either may not be tested currently or have to go through more time-consuming and labor-intensive testing. For owner agencies, the ABQT could be used as a quick screening test on the many samples they collect from contractors. The screening test could be conducted as samples are received, which could potentially allow identification of out-of-specification samples more quickly. For binder suppliers and terminals that receive shipments of binder from another supplier, the ABQT could be used as a quick screening test to get a general idea of the binder properties. Suppliers and terminals could also use the ABQT to quickly test the properties of binder mixes they produce. At mix plants, contractors could quickly test samples from shipments they receive to ensure that there were no issues during transport. Contractors could also quickly test binder before it is added to an asphalt mix to ensure that there are no major issues with the storage tanks.

Although the use of the ABQT as a quick screening tool seemed like a promising use case for stakeholders, the use of the ABQT as an additional certification test or as a replacement for any current certification test was a concern for many stakeholders (the ABQT was not considered a viable replacement option). Stakeholders raised concerns regarding the ruggedness of the device. To ensure stakeholder confidence that results would be consistent for samples of the same material at multiple locations, there would need to be a standard procedure for calibrating the ABQT. Stakeholders who used the device said that it took them a little time to learn how to calibrate the device properly before each use.

5.1 Market Readiness of the ABQT

To provide a framework for evaluating the ABQT’s market readiness and potential barriers, the evaluation team reviewed the five product characteristics defined under Rogers’ Diffusion of Innovation Theory, which explores why, how, and how rapidly innovations are adopted (Rogers, 2003). The five product characteristics are the following:

• Relative Advantage. Relative advantage is the degree to which the innovation is an improvement over alternative technologies. The ABQT’s main relative advantage is its ease and speed of use. The test takes minutes to run and requires only a 3-ounce tin of binder heated to 25°C. The device’s ease of use may allow owner agencies to conduct testing on many more samples, improving their quality control (QC) procedures. The ABQT’s closest alternative device, the Dynamic Shear Rheometer (DSR), is comparable in price (about 25% more expensive) but takes significantly more time to prepare the clean sample for each test. The daily throughput of ABQT sample testing is about three times that of a DSR. Additionally, the ABQT predicts the high and low temperature grades of the binder’s sample with a single test of unaged binder, whereas the DSR does not provide that information. These differences give the ABQT a clear advantage.

• Compatibility. Compatibility is how consistent the new technology is with the current needs of potential adopters. This aspect may be the most significant hurdle to the adoption of the ABQT. Current sampling and testing procedures are entrenched in the industry, and changes require input and buy-in from many stakeholders. Additionally, the cost of the equipment is an important consideration for stakeholders because any additional testing equipment needs to be cost-effective and approved by management. Although quality is important in the industry, additional quality measures need to demonstrate that they would improve the final asphalt product.
• Complexity. Complexity is the ease with which the innovation can be understood and used. This characteristic is a strength of the ABQT because it is a self-contained product. Minimal training is required to execute the ABQT’s main functions.
• Trialability. Trialability is the ability of potential adopters to experiment with the innovation. The portability and ease of use of the ABQT make it easy for different stakeholders to test the device. The device has already been loaned to five state DOTs for testing. Loaning or low-cost leasing of the device would be relatively simple and could provide the exposure needed for widespread adoption.
• Observability. Observability is the ability of the innovation to provide tangible results. The ABQT was designed to output a PG for a binder sample using its ANN model. The state DOTs that evaluated the ABQT stated that the device reported the correct PG of a binder sample 98% of the time.

From a technical perspective, the ABQT performs well in a market readiness analysis, although some areas need to be finalized, such as approval of a standard procedure by AASHTO on how best to update the ANN software source data. From an awareness, acceptance, and confidence perspective, additional outreach is needed before widespread adoption will take place.

5.2 General Barriers to Adoption

The evaluation revealed several potential barriers to adoption that were shared across stakeholder groups throughout the supply chain. The three most commonly cited were

• The price of the unit,
• The ABQT not being a replacement for current acceptance testing processes, and
• The ABQT’s lack of certification as an accepted testing method.

5.2.1 Price

One of the biggest hurdles for adopting the ABQT is the price. The current quoted price from its manufacturer, LTI, is $38,000 to $40,000. However, LTI indicated that the price could drop if the manufacturer scaled production. This price is comparable to the price of other devices currently used for binder testing, as shown in Table 5-1. To determine the full PG of the binder sample, the sample must be put through both the Bending Beam Rheometer and the DSR tests as virgin binder, then it must be age conditioned in the Rolling Thin Film Oven and the Pressure Aging Vessels, and then retested using the DSR. The benefit of the ABQT is that it is a single device that will give an accurate estimate of the PG of a binder sample, whereas all four of the other devices detailed in Table 5-1 need to be used to find the full PG of a binder sample. Nonetheless, many DOTs said that equipment purchases costing $15,000 to $25,000 require upper management approval, which is a disincentive for the adoption of additional equipment.

In addition to the purchase price of the ABQT device itself, adoption/operating costs were a concern for some stakeholder groups across the binder supply chain. For example, most asphalt mix plant operators do not conduct any on-site testing, so in addition to purchasing the ABQT,

Table 5-1. Test method costs.

^a Total 28 hours for full performance grading (first four test methods listed in Table 5-1) of 11 binders.

^b Total 8 hours for full performance grading of 30 binders.

plant operators would need to modify their processes to allow for testing (however brief it may be) and dedicate labor resources to managing the testing process.

For binder suppliers, the ABQT would also represent an additional cost because it is unlikely (at least in the short term) to replace the need for any other equipment they already maintain for testing. Furthermore, costs could be a barrier because the ABQT would add additional tests that would not replace existing testing. Even though the time commitment for use of the ABQT is minimal, many companies already have limited resources for testing and are reluctant to add any additional steps to their processes.

Like binder suppliers, owner agencies that choose to use the ABQT would not be able to reduce equipment costs elsewhere in the short term. The labor and process implications are small but not negligible for DOTs. However, on the positive side, ABQT use could incentivize DOTs to add additional requirements, such as testing more samples from asphalt mix plants, hence enhancing the quality assurance (QA) process. Although the additional labor may cost more, agencies may decide that reducing the likelihood of poor-quality binder affecting asphalt quality on a roadway is worth the cost.

5.2.2 The ABQT Would Not Replace Current Acceptance Tests

Another barrier identified is that the ABQT would likely not replace any current acceptance tests that are conducted because required acceptance testing procedures are very explicitly defined in the AASHTO standards. Although the ABQT may be an excellent screening or QC tool, traditional acceptance testing would be needed as a follow-on when certification under AASHTO standards is required. Additionally, although the ABQT does measure deformation and recovery, producing results similar to a DSR, the ABQT is conducted only on a sample that has not been conditioned by the Rolling Thin Film Oven or the Pressure Aging Vessel. Stakeholders would need to be confident that without the binder aging processes included in other tests the results of the ABQT would still be reliable.

5.2.3 Acceptance and Certification

For industrywide adoption of the ABQT, the technology would need exposure and corroboration by trusted, impartial stakeholders. Trade organizations such as AASHTO could have a major impact on the adoption of the ABQT device because they would give the device exposure to industry professionals and give them confidence that the results are accurate and reliable.

A concern for many stakeholders regarding the ABQT was the lack of a standard testing procedure approved by a trade organization, specifically AASHTO. Multiple stakeholders stated that they might not adopt the ABQT even as a screening tool if it did not have a standard procedure approved by AASHTO. The AASHTO standard specification provides a rigorous review of the testing methods, results, and limitations by a panel of industry experts, and that process would be useful in exposing industry professionals to the device. Stakeholders associated with AASHTO indicated that developing a presentation on the ABQT device for the liquid asphalt subcommittee would be a good first step in raising awareness of the device among AASHTO members. However, AASHTO standard specification approval is a rigorous process involving the interests of many different stakeholders, which could make it a hurdle for the ABQT.

Approval from AASHTO as a standard specification would be a key initial achievement. If the ABQT was an accepted testing procedure with an AASHTO specification, state DOTs might be more likely to include it in their standard specifications. Additional testing without regulatory pressure is generally unlikely in the construction industry because it cuts into project budgets and timelines. The widespread implementation of the ABQT device may require regulatory changes from state DOTs or national materials testing organizations.

In the construction industry, regulation is a major driver of the QC activities that are conducted. State agencies requiring the ABQT would provide a major push toward widespread adoption of the ABQT. Widespread adoption would likely not happen without an AASHTO standard specification and widespread familiarity and comfort with the device.

5.3 Individual Stakeholder Group Business Case and Adoption Analysis

5.3.1 Owner Agencies

The most likely early adopters of the ABQT are the state DOTs that would use it as a screening device for the samples they collect from contractors during projects. The DOTs interviewed did not think the ABQT could replace or alter the number of full tests they currently conduct. Thus, adoption of the device would not lead to labor or equipment cost savings.

However, as a screening tool, the ABQT offers several attractive features. Testing capacity is an issue for most owner agencies. Many are either not able to test every sample collected or there is a long lag between when the sample is collected and when the test is conducted, at which point the project may already be finished. The ABQT could allow every sample to be screened, and then samples that failed the screening could be prioritized for full testing.

Many owner agencies have regional offices where samples are initially sent. The samples are then shipped to a central state office that has the full suite of laboratory equipment for binder testing where the samples can be tested. Owner agencies expressed interest in using the ABQT at the regional offices to test samples quickly to detect any that were not within the correct specifications. For these samples, the contractor could be immediately notified and the cause of any issues quickly determined. States reported that they tested between 500 and 2,000 samples annually, and the turnaround time for results could be from 2 weeks to 2 months. Testing at regional labs could decrease by days or weeks the time it takes to notify contractors of problems with a binder.

All state DOTs interviewed said that if the ABQT were adopted, they did not think it would significantly change the number of employees owner agencies use for binder testing. Most agencies have only a couple of people who run the current binder tests, and some have only one person. However, the owner agencies did say that the ABQT would allow them to be smarter about testing. They could screen samples and then prioritize the testing of samples that have tested out of specification or shown something concerning with the ABQT. The number of full tests conducted would likely not change.

Although many owner agencies expressed concern about asphalt quality in their states, there are very few occurrences across the country of binder samples not meeting specifications in testing. Most estimates of tests not meeting specifications were approximately 1%, and many of the samples that failed were only slightly out of specification. Owner agencies often levy fines based on how out of specification a sample is and apply that fine to a volume of asphalt in which the out-of-specification binder was used, based on the sampling interval. In the last couple of years, asphalt has been removed and replaced in very few instances. In the quantitative analysis that follows, avoiding the need to remove and replace asphalt represents a very small fraction of the estimated benefits of the ABQT.

Owner agencies generally set testing standards for the states where they are located, so their adoption of the ABQT is important for other stakeholders to gain confidence. Owner agencies generally test the binder product from samples taken right before the binder is added to the asphalt mix, so owner agencies are supportive of any additional testing measures in the supply chain that can catch problems before the binder is even sampled at the mix plant.

Owner agencies such as county and city DOTs are not likely to be early adopters of the ABQT. Because of a lack of capacity and access to testing equipment, very little additional testing is conducted for jobs for these owner agencies. Furthermore, on the roads that they own, local agencies tend to use more basic binders (binders without additives and modifiers) and just a single binder. These agencies tend to trust certifications from suppliers and have not expressed interest in additional binder testing.

5.3.2 Asphalt Binder Suppliers

The asphalt binder supplier’s stakeholder group includes a range of potential users, from refiners to binder producers to terminals that store binder. Binder suppliers are the source of the binder used at mix plants, so the binders that suppliers produce and ship need to be of the correct grade and meet technical specifications.

Although the ABQT would not be used as a certification test, binder suppliers might have three potential use cases. Suppliers could use the ABQT as

1. A quick test to calibrate binder received from another supplier or refinery. This check could serve to ensure that the correct product was received or, in some cases, it could help to get a basic idea of the type of product received if the supplier was unfamiliar.
2. A quick check on the binder during the blending process to make sure polymer or other admixtures are being added correctly without having to run any of the more complicated tests that are run when the mix is complete.
3. A quick test before a load of binder is sent out to make sure the correct binder has been loaded into the shipping container. Container errors were cited as one of the major reasons for binder contamination.

Binder suppliers generally conduct their QC testing and submit a QC testing plan to the state agency overseeing their work. To verify the QC processes, the state agencies may collect samples

quarterly or annually to test and compare to the results from the suppliers’ testing. Many binder suppliers’ QC plans require them to run the full suite of either the AASHTO M-320 tests or the M-332 tests on each batch produced. Suppliers indicated that this testing regime would not change if the ABQT were to be adopted; therefore, suppliers would see no significant change in their testing costs.

The suppliers interviewed did not think the use of the ABQT would generate significant delivery delays. However, if screening using the ABQT did result in time delays, this could be a barrier to adoption.

One of the most frequently mentioned benefits was reducing “reputation” risk by avoiding lower-probability catastrophic events associated with binder issues. One incident can do significant damage to a company’s reputation and hurt future/repeat business opportunities.

5.3.3 Asphalt Mix Plants

Asphalt mix plants are the group that would be most reluctant to adopt the ABQT at their sites. Currently, mix plants and asphalt contractors generally do not add additional testing and sampling to their processes unless a regulatory agency requires it. The mix plants tend to look at binder quality as the responsibility of the binder supplier and accept the certification the supplier provides for its product.

Although mix plants would be reluctant adopters, there could be value in mix plants using the ABQT. Even though mix plants tend to rely on binder suppliers’ certification of the quality of their binders, a mix plant could still face reputational risk if it uses an incorrect binder. Using the ABQT to sample loads of binder as they come into the mix plant would be of value to society as a whole in the rare case where a binder issue could be mitigated.

Additionally, many mix plants store binder in tanks on site. Binder problems can occur in binder storage if the tanks are not completely emptied of other, previously stored products or if the tank has a leak that allows binder contamination. Testing binders quickly could eliminate concerns related to binder storage.

Recently, some mix plants have started to use additives in binders that are mixed in line as the binder is added to the asphalt mix. Mix plants could use the ABQT to test binders they adjust quickly before adding the binder to the asphalt mix. This would allow mix plants to detect problems before the owner agency does.

5.3.4 Private-Sector Labs

Private labs are a small stakeholder group in the industry and are unlikely to adopt the ABQT. Most states have their own testing labs, and many binder suppliers manage their own testing labs. One responsibility private testing labs have in the industry is as “referee testers” that compare owner agency and supplier test results of samples. Private labs can also be used as overflow testing facilities when other stakeholders exceed their testing capacity. The services of private testing labs depend on the needs of states and other stakeholders in the industry, so private labs would probably not adopt the ABQT unless other industry stakeholders adopted it widely. Private labs generally do full certification tests on all of their samples or very specific tests that clients request; therefore, it does not seem likely that private labs will adopt the ABQT in the near term.

5.4 Additional Opportunities for the ANN

Another topic discussed during interviews was the advantages of the ANN used in the ABQT and its potential additional applications. One of the main advantages of the ABQT is its ability to take data from a testing procedure that is nearly as simple as the standard penetration test and use the ANN that the ABQT is equipped with to identify the PG of the binder sample. Stakeholders with experience using the device touted the benefits of the ANN but also mentioned a couple of pain points. First, stakeholders did not know how the ANN functioned to identify binder grades, so if stakeholders had issues, they needed to reach out directly to the ANN developer (Raj Dongre). Furthermore, to train the ANN, users had to send samples to the developer/manufacturer to load into the software and have the developer/manufacturer send back an update. ABQT users said that they would prefer to have an ANN that they could update themselves or have it be connected to a network so the database could be easily updated and they could share data with other users.

Some users also mentioned that the ANN could be a useful stand-alone piece of technology. Users asked whether the ANN could be applied to the data from an existing testing device that many stakeholders already use, such as a DSR. Training the ANN to process data from an existing testing device that many labs already have could make it more accessible to more users and eliminate some issues related to maintaining new equipment.

5.5 Summary of the Benefits of ABQT Adoption

The main benefit of ABQT adoption is assisting owner agencies with testing their backlog of binder samples and providing more timely results to project managers in the field. The ABQT would allow DOTs to test more samples, which would help identify more failed samples and identify them much sooner, reducing the amount of out-of-specification binder going into asphalt road pavement. In this way, the quick screening test could reduce the amount of subpar binder in asphalt pavement as corrections are made in the field before the project is complete and equipment is moved to the next site.

Although adoption of the ABQT by owner agencies would not change the number of full tests that are conducted using current testing methods, the ABQT would augment the current testing process so that owner agencies could better target binder samples that may have problems.

There are relatively few instances of failed asphalt binder tests and even fewer instances of asphalt being removed and replaced because of using an out-of-specification binder. Nonetheless, binder quality is a prevalent concern in the industry. Because many states are not able to test every binder sample they collect and notifications of failed, out-of-specification binders are often delayed, a small amount of subpar binder asphalt is used in road pavement each year. The ABQT could help reduce that amount, and this scenario is modeled in Section 6.3 of this report.

The use of the ABQT device as a screening test would enable owner agencies to prioritize which binder samples should undergo the full suite of acceptance tests first. This prioritization would improve the QA process by allowing all samples to be screened quickly. Samples that failed the ABQT test could then be expedited for full testing, and the results could be delivered to the field more quickly for samples of concern.

In addition to the maintenance cost benefits of better-performing asphalt, other potential benefits of ABQT use include safety and environmental benefits. For safety, decreased maintenance reduces the site time for road workers and decreases the chances of workplace accidents. Additionally, having fewer work zones improves overall safety for motorists. With respect to

environmental benefits, improved binder quality can enable better-performing roadways, which can improve fuel efficiency for motorists. Even though most SMEs agreed that these additional benefits were likely to exist with improved testing, all thought the potential beneficial impact attributable to the ABQT device would be small and not possible to measure with any accuracy.

Finally, one limiting factor in making the business case for ABQT adoption is that attributing benefits to improved binder quality alone is difficult. All SMEs said that teasing out the impact of the binder on the overall quality of the asphalt used on a road is very hard. Many different factors can affect the quality and performance of asphalt pavement. Some of these factors have to do with construction methods, such as inadequate compaction during construction and construction occurring in extreme weather conditions. Other factors relate to the mix itself, such as using incorrect or low-quality aggregates or mixing the asphalt at improper temperatures. Hence, determining the benefits of ABQT use will always include an element of uncertainty. However, all SMEs agreed that enhanced testing would lead to improved asphalt, which has economic and social benefits.