- 13.2-FH1: Development of Innovative Welding for High Performance Bridge Steel
Steel bridge fabrication has changed little since the 1950s when welding steel began to dominate over riveting. The recent 20 years has seen two innovations in steel bridge fabrication. One has been the advent of high performance steels (HPS) in the mid-1990s that provided higher yield strengths, higher fracture toughness, and most importantly, an increased weldability over conventional grades of bridge steel. Two, was the official adoption of electroslag welding into the American Welding Society (AWS) D1.5 Bridge Welding Code in 2010. Elecroslag welding is one of five welding processes recognized by AWS for steel bridge fabrication, but the majority of steel bridge fabrication still uses the submerged arc welding (SAW) process.
One of the most time consuming welds to make in bridge fabrication are butt splices between standard mill plates to create plates longer than the steel mill can deliver. Typical practice would be to use multi-pass SAW to make these joints and this becomes quite costly when the plate thickness is greater than 1 inch due to the extensive preparation, number of passes, and volume of weld metal. For instance, to butt weld a typical 3 inch thick by 30 inch wide girder flange would take 15 hours with SAW. Electroslag welding is specifically tailored for welding thick plates together in a single pass, and the same flange could be welded in 30 minutes. Additionally, electroslag welds have a much lower propensity for developing internal weld defects which can plague SAW leading to costly repairs and time delays.
Currently AWS D1.5 precludes electroslag welding of HPS grades of steel and for all fracture-critical members, because the process was never demonstrated for these applications. The specific concern with elecroslag welding HPS is the very high heat input having deleterious effects on the heat treatment of the HPS steels. The previously developed electroslag process consumables and welding conditions may have to be modified for joining HPS to ensure that welded joints have no rejectable discontinuities and will have adequate strength and toughness in both the weld metal and heat-affected zones of the welded joints.
The productivity of electroslag welding has the potential to speed up steel bridge fabrication and using HPS material can increase the reliability of new bridges. However, there has yet to be a synthesis of these two innovations to work together, and further electroslag weld process development must be performed so the process can be proven viable for joining of HPS to HPS, as well as hybrid welding of HPS to conventional bridge steel.
While electroslag is one of the methods that can be used to achieve this result, other innovative welding methods will also be considered. However, other methods should consider that standard mill widths of steel plate are 72, 96, and 120 inches wide and hence, the longest welds for the process will be this range. The lengths of plate being fused could be as long as 85 feet too, so other innovative processes should consider feasibility of handling plates of these sizes during welding. In addition, technologies beyond electroslag shall be more efficient, in regards to the total time to create a weld, than SAW at plate thicknesses over 1 inch. The finished weld should also have no rejectable discontinuities and will have adequate strength and toughness in both the weld metal (if used) and heat-affected zones of the welded joints.
The developed process will meet the FHWA National Leadership goal of advancing innovation by bringing together two existing technologies to help expand steel bridge fabrication possibilities, along with reducing fabrication costs and lead time. Once the process innovation is complete, it is expected that welding equipment manufacturers will be able to sell more machines to steel bridge fabricators, and steel bridge fabricators will become more competitive with the efficiency gains from electroslag or other innovative welding processes.
Expected Phase I Outcomes:
The objective of this phase is to conduct a feasibility study to explore and identify innovative welding process variables and/or consumables for application to HPS. The two areas of concentration will be (1) research consumable chemistry requirements, if required, and the resulting weld metal chemistry to achieve (a) the correct strength level per grade and (b) a weld metal microstructure with the maximum level (at least that of meeting Zone 2 requirements) of impact toughness, and (2) identifying processes that will reduce the heat input to a minimum level that can be used consistently and practically to achieve quality welds in a production environment. This phase may include production of trial welds.
Expected Phase II Outcomes:
Phase II will include the production of trial welds (if not already performed as part of the Phase I). The Phase II outcomes build upon the lessons learned in Phase I and will result in full optimization development of innovative welds between HPS and HPS, and HPS to conventional steel through a rational testing matrix of trial welds looking at the critical variables identified in Phase I.
- 13.2-FH2: Game-based technology and Database to Train Pre-Drivers, Young Drivers, and Older Drivers to Detect Traffic Hazards and Respond Appropriately
Motor vehicle crashes killed an average of 40,398 people in the U.S. each year from 2000 through 2010, despite declines to 37,423 in 2008, 33,808 in 2009, and 32,885 in 2010 during harsh economic conditions from which the country is slowly recovering (National Highway Traffic Safety Administration, 2012). As a cause of death in the U.S. in 2009, traffic crashes ranked first among both 5-14 and 15-24 year olds, third among 1-4 year olds, and fifth among 25-44 year olds (Kochanek et al., 2011). This human tragedy is unacceptable and creative new approaches are needed. As researchers recently reported in the journal Accident Analysis and Prevention:
Hazard perception in driving refers to a driver’s ability to anticipate potentially dangerous situations on the road ahead ... This particular ability has generated interest among the road safety community because, to our knowledge, it is the only driving-specific skill found to be associated with crash risk…
We examined the proposal that hazard perception ability is suboptimal even in highly experienced mid-age drivers. First, we replicated previous findings in which police drivers significantly outperformed highly experienced drivers on a validated video-based hazard perception test, indicating that the ability of the experienced participants had not reached ceiling despite decades of driving. Second, we found that the highly experienced drivers’ hazard perception test performance could be improved with a mere 20 min of video-based training, and this improvement remained evident after a delay of at least a week. One possible explanation as to why hazard perception skill may be suboptimal even in experienced drivers is a dearth of self-insight, potentially resulting in a lack of motivation to improve this ability. Consistent with this proposal, we found no significant relationships between self-ratings and objective measures of hazard perception ability in this group. We also found significant self-enhancement biases in the self-ratings and that participants who received training did not rate their performance (either in real driving or in the test) as having improved, contrary to what was indicated by their objective performance data.
Thus, current scientific findings suggest the potentially substantial safety benefits of using technology, such as PC/TV-based videogames and/or driving simulator technology, combined with a comprehensive traffic hazard-response database, to train pre-drivers, young drivers, and older drivers to detect and appropriately respond to traffic hazards.
Expected Phase I Outcomes:
Outcomes expected from Phase 1 include a feasibility study, design, and outline of a game-based technology (software, hardware, or other), such as but not limited to a PC/TV-based videogame or driving simulator, and a traffic hazard-response database, to educate and train pre-drivers, young drivers, and older drivers to detect and appropriately respond to a variety of traffic hazards. The feasibility study will identify and summarize the main safety hazards for different subject groups and propose corrective measures. The study will also identify potential customers for this product, which may include insurance companies, driving schools, public school systems, safety advocacy organizations and groups, etc.
Expected Phase II Outcomes:
Outcomes expected from Phase II include the production and demonstration of a working prototype of the technology studied during Phase I, and testing, field evaluation, and substantial refinement of the prototype developed, to maximize traffic hazard detection and appropriate response rates, as well as the long-term duration of enhanced traffic hazard detection and appropriate response rates, among pre-driver, young driver, and older driver populations as demonstrated by rigorous experimental methodology, data reduction, statistical analysis, and exposition in a form suitable for refereed journal publication.References:
National Highway Traffic Safety Administration, 2012. Fatality Analysis Reporting System (FARS). Downloaded on 24 July 2012 at http://www.nhtsa.gov/FARS.
- 13.2-FM1: Affiliation Strength/Risk Model Development for Motor Carrier Succession
The Federal Motor Carrier Safety Administration (FMCSA) is responsible for regulating the safety of interstate truck and bus travel in the United States. The primary mission of FMCSA is to reduce crashes, injuries and fatalities involving large trucks and buses.FMCSA’s strategic framework is built upon three core principles:
- Raise the bar to enter the industry;
- Require operators to maintain high safety standards to remain in the industry; and
- Remove high-risk operators from our roads and highways.
The vetting process implemented within the FMCSA’s Office of Registration and Safety Information supports all of these initiatives by assuring that new applicants meet FMCSA’s standards for fitness, willingness, and ability to comply with all applicable federal statutes and regulations by checking for signs that a new applicant is not a reincarnated version of an existing high-risk operator. These initiatives set a high bar to obtain operating authority and close loopholes for those high risk operators to reincarnate themselves with a clean slate and, hence, keep them off public highways.
FMCSA already employs a proprietary risk-based screening process which uses a sophisticated matching algorithm to screen and assign risk to an applicant using primarily federal sources of data. This solicitation is seeking innovative approaches, alternate methods and public/private data sources to confirm or further expand robust automation methods that are part of its screening process.
The primary purpose of this topic is for the Offeror to use operating authority application information specified on the application form (See References 1 and 2) and compare it to the similar information on file for a list of motor carriers and identify the probability of potential affiliation between the applicant and each of the carriers of interest (i.e. development of a robust affiliation strength model with use of publicly available data sources).
FMCSA is primarily interested in
- Surveying of publicly available data sources (such as States’ data) that can be automatically cross-checked against that can validate submitted information or hint for potential affiliations;
- Surveying of affiliation strength/risk models that may be used in other business models or by other Federal or State Agencies;
- Identification of private data that could provide incremental benefits;
- Development and use of complex matching algorithms that may take into account typos, different abbreviations, use of short names, text order differences;
- Confirmation of application data validity to the extent possible such as business address;
- Use of web-search algorithms that can be automatically assimilated into useful measures;
- Development and use of probability measures for assessing affiliation strength; and
- Development of a self-learning framework and adaptive methods to automatically update the model parameters based on application disposition decisions.
The Contractor will be required to sign a non-disclosure agreement to receive sample data which can be used to develop and test out proposed methods. There are about 50,000 applications per year, each of which would need to be automatically processed for affiliation strength assessment with respect to a list of other motor carriers of interest which may be a subset of the ~725,000 motor carriers to be specified by FMCSA. Each application would not need to be checked against all motor carriers of interest and the Offeror would have latitude to further scope down the screening methodologies intelligently based on the research conducted within this project.
The entire solution would need to be fully automated. It would need to input a set of text fields from an applicant and a set of text fields from an existing company and use the underlying company information and the identified public sources of information to output a probability measure of affiliation strength between the two companies. The algorithm must run reasonably fast such that one application can be batch processed against a large number of potential other companies and the entire automatic assessment process can be completed in reasonable time (reasonable level to be defined jointly between the Contractor and FMCSA during Phase I).
Expected Phase I Outcomes:
Outcomes expected from the Phase 1 include surveying and documentation of all available public and private data sources and uses of other affiliation strength/risk models. In addition, a detailed concept that demonstrates the viability of developing complex affiliation risk model that would work within the context of FMCSA’s needs is expected to be delivered. Computational needs and processing time assessments will have to be quantified. Expected ranges of effectiveness measures would need to be developed.
Expected Phase II Outcomes:
Phase 2 efforts would prototype the Contractor’s approach to validate the affiliation risk model. Furthermore, a detailed experimental plan for assessing the efficacy of the solution would be formulated along with updated cost-benefit projections based on development activities.
- 13.2-PH1: Pipeline Integrity Assessment Using In-Line Inspection
There is a current need better pipeline inspection technology to enable improved inspection of both oil and gas pipelines for internal corrosion, external corrosion, mechanical damage, and longitudinal and transverse cracks. A new and evolving interest across the industry is for an inspection technology that can measure longitudinal strain. This Small Business Innovation Research (SBIR) topic seeks an alternative means for enhanced in-line inspection (ILI) tools that can be easily deployed, ideally at a lower cost and with fewer personnel and infrastructure compared to existing tools. The tool must:
- Keep up with production flow rates and resolve defects with similar or improved reliability and resolution compared to existing, commercially available technologies;
- Address a substantial percentage of pipelines that are currently inspected;
- Relatively lightweight and limited in axial length to enable easy transport, launching, and retrieval;
- Low initial and operating costs to enable frequent deployment;
- Enable difference imaging to determine whether defects are growing and to eliminate dormant responses that are inconsequential and;
- Finally, include software support tools so that only minimal post inspection analysis is required to enable operators to deploy these tools at will, without incurring the high costs and burdens associated with some ILI implementations.
One goal is to enable this ILI tool can be used anywhere that cleaning tools are used, even in previously unpiggable lines. The goal is to encourage more repetitive ILI runs and wider use while ensuring safety of the hazardous liquid pipeline infrastructure.
Sub-topic challenge– Proposals are being sought to develop a prototype integrated cleaning tool/ILI tool that is easily deployable, is low-cost, and requires minimal post-inspection data analysis. The solution should not include heavy magnets, coupling, or other complexities that will increase cost. The solution should support hazardous liquid pipelines while providing sufficient resolution for all defects that can be detected with current technologies.
An ideal integrated ILI-cleaning tool would have the following attributes:
- Safely transportable by two operators, and can be easily installed for inspection of small diameter linepipe;
- The capability to detect internal and external defects with at least the same resolution as state-of-the-art magnetic flux leakage (MFL) ILI tools.
Focus Area 1 - Expected Phase I Outcomes:
A successful Phase I will demonstrate, in a laboratory environment, the ability of a proposed prototype in-line inspection tool to meet the following design objectives:
- Low initial and operating costs;
- Similar or improved detection capabilities compared to existing methods;
- Ease of handling (transport, launching, and receiving) similar to a cleaning tool;
- Ease of data interpretation;
- Incorporation of required features (odometers, pig trackers, etc.); and
- ILI capability for hazardous liquid pipelines.
Future Work for Focus Area 1 - Expected Phase II Outcomes –:
Phase II will include the fabrication and testing of a working prototype, including an ILI pull-test on representative samples with representative defects under representative conditions.
- 13.2-PH2: Modeling cathodic protection penetration on new construction pipelines incorporating all types of "foam" sack breakers and supports
When a pipeline is constructed a ditch is dug to applicable depths based on federal regulation and is prepared for the pipeline that will be laid within the construction ditch. When the pipeline is placed in the ditch it requires support and padding to protect the coating and align it to the topography of the ditch in preparation for back fill. There are many types of material that can be used to provide support within the construction ditch. These supports are typically constructed with sand bags, hay bales, oak cribbing, or spayed urethane foam. Likewise, in the event that water enters the construction ditch water breakers are used to prevent and sectionalized any flowing water. This prevents flooding, washout, soil erosion, and potential ditch collapse from happening. These water breakers are typically constructed with sand bags or sprayed urethane foam. Construction practices for ditch pipeline supports and water breaks favor products that will satisfy the design requirements at the lowest total cost over the life of the project.
With the rising cost of labor, materials, and transportation of sandbags for padding and breakers during pipeline construction, urethane foam breakers and padding have become an economical solution for many service owners and general contractors. Additionally, due to the fast pace of today's construction processes and the time constraints placed on the completion of projects by pipeline owners due to service demands, the time saved by using sprayed foam breakers and padding has made it a popular alternative to the traditional sandbag method. Time and money savings also appear in the general contractor's bottom line, since backfill crews and machinery will reduce down time due to the waiting period involved with installing sandbag breakers, padding, or pipe support.
The advantages of urethane foam over the use of sand bags include the following:
- Foam barriers do not deteriorate or degrade over time like sandbags;
- Urethane foam conforms to any shape or configuration of ditch and offers the advantage of immediate backfill;
- Urethane foam pillow pads will compress and conform to the pipe with a weight load whereas sandbags (especially frozen ones) may dent the pipe;
- Urethane foam greatly reduced transportation cost to the job site;
- Additional savings will come in the future as the cost of pipeline upkeep and maintenance will be reduced; and
- Since foam breakers are sprayed around the pipe in-place, they adhere to the pipe itself and only move if the pipe moves.
Along with the design considerations (such as length, width, the depth of foam needed to support a pipeline filled with water without denting the pipe, and the minimum clearance above rock) pipeline operators must ensure their pipelines meet Federal regulations for natural gas and hazardous liquid pipeline safety regulations on corrosion prevention as related to cathodic protection (CP). Since urethane foams are highly dielectric the possibility of shielding CP is high. Other concerns in the use of urethane foams are structural integrity, water infiltration of the foam, and potential buoyant forces in saturated ground or rising water tables. The foam should be reviewed for durability to support the pipeline weight over the operational life of the pipeline. For reference, applicable Federal pipeline safety regulations are listed below:
§192.461 External corrosion control: Protective coating.
§192.463 External corrosion control: Cathodic protection.
§195.557 Which pipelines must have coating for external corrosion control.
§195.559 What coating material may I use for external corrosion control.
§195.563 Which pipelines must have cathodic protection.
Special note: The National Association of Corrosion Engineers (NACE) has published an industry accepted practice—NACE SP 0169 (which is also incorporated by reference see § 195.3) — to quantify the adequacy of cathodic protection with the following statement:
“Cathodic protection required by this Subpart must comply with one or more of the applicable criteria and other considerations for cathodic protection contained in paragraphs 6.2 and 6.3 of NACE SP 0169.”
Sub-topic challenge– Proposals are being sought to develop a model that analyses and quantifies the CP penetration, as related to the Pipeline Safety CP requirements, through all types and sizes of “foam” sack breakers and supports. The model must take into consideration foam type and the length and thickness of breakers and/or supports. The model must also take into consideration the exposure to a variety of soil types and conditions, including but not limited to moisture content, temperature, and depth of cover. An ideal model would have the following attributes:
- Dielectric leakage considerations for the foam sack breakers and supports in addition to the soil and surrounding conditions.
- Predetermined look up tables for known resistance values of given materials.
- A visual display of diagramed configuration with various paths of CP values.
- Durability of the foam material to support the pipe over the operational life of the pipeline.
- The effects of buoyancy force from the foam padding or water break structure when in saturated soil or within rising water table on the pipeline and the pipelines coating. Distinction of the buoyancy force should be made on open versus closed cell urethane foam.
Expected Phase I Outcomes:
A successful Phase I will demonstrate, in a portable computer configuration, the model’s capability to quantify various CP paths and estimated values based on limited data input while meeting the following design objectives:
- Low initial and operating costs;
- Similar detection capabilities compared to existing methods;
- The ability of the model to configure and display various CP paths and values;
- Ease of data interpretation;
- Durability of the foam to support the pipe over the operational life of the pipeline;
- The amount of Buoyant force that could be applied due to saturated ground or rising water tables; and
- An operational instruction manual for the model.
Expected Phase II Outcomes:
Phase II will include:
- Data collection from in-field demonstrations of CP penetration readings of foam sack breakers and supports;
- Expansion of data in look-up tables for known resistance values of given materials.
- Recalibration/validation of the model based data findings from in-field testing. Refine update and display of viable commercial model at a public pipeline forum.
- 13.2-PH3: Develop and demonstrate new non-destructive evaluation methods to quantify remaining strength of line pipe steel and or pipeline fittings
The U.S. Code of Federal Regulations (CFR) Title 49, Parts 192 and 195 stipulates that ASME B31G or RSTRENG be used to assess the remaining strength of corroded pipe. A review of existing burst test data raised some concerns that use of these methods can, in some instances, result in predicted failure pressures that are greater than the recorded burst pressures from actual tests. No burst testing data exist on steel pipeline fittings.
Industry has also researched methods for assessing the remaining strength of corroded pipelines. This has led to the development of new criteria and has extended the range of assessment methods to include numerical analysis. While there has been substantial progress, there are areas where the existing criteria require improvements, including steel pipeline fittings. Issues identified include limitations on the interaction of closely spaced defects, the effects of external loading, and cyclic pressure loading. Furthermore, as operators start to use higher strength materials, there will be an increasing need to assess the integrity of high strength steel pipeline fittings that have been corroded while further validating the application of existing criteria and models for these materials.
Past work by industry and the U.S. Department of Transportation’s Pipeline and Hazardous Safety Administration (PHMSA) has funded research to address these issues in recent years on pipeline steels. The work has included a program of materials testing, finite element (FE) analyses, and full scale burst testing to develop methods for assessing corrosion damage in pipelines of strength grade up to X100. Reports from this work are available at: http://primis.phmsa.dot.gov/matrix/PrjHome.rdm?prj=171
Corrosion metal loss is one of the major damage mechanisms to transmission pipelines worldwide. A corrosion metal-loss defect further reduces the strength of the damaged pipeline sections while introducing localized stress and strain concentrations. Several methods have been developed for assessing the remaining strength of corroded pipelines, such as the ASME B31G and RSTRENG models. These models were derived from experimental tests and theoretical/numerical studies of the failure behavior of corroded pipelines. The test pipes contained either corrosion metal-loss defects or simulated metal-loss defects and featured materials with relatively high toughness properties for X65 and above and lower toughness properties for X60 and below. The early burst tests used vintage pipe with low toughness properties. Plastic deformation and collapse of the ligament or surrounding material determines the failure behavior of the corroded pipe. In principle, the existing assessment methods are only applicable to pipelines with toughness levels that are sufficient to prevent a toughness-dependent failure.
The research completed did not include analysis of burst test data on steel line pipe with real corrosion defects in strength grades above X65, as the data were not available. To address this gap, a focused program of full-scale tests is recommended on higher strength line pipe of strength grades above X65 with electro-chemically induced, simulated corrosion defects. These defects can be produced using electrochemical means to approximate real corrosion in the field, as opposed to flat-bottomed rectangular machined patches. Failure pressure predictions using ASME B31G, Modified ASME B31G, and RSTRENG should then be compared to the recorded burst test pressures to confirm that these methods are applicable for higher strength pipelines.
Mechanical properties of pipe metal help define the principal characteristics of its technical state. These properties can change (degrade) during long-term operation not as a result of an aging process but rather from exposure to cyclic pressures, extreme temperatures, excessive forces or detrimental environmental conditions. Heat input during the coating process may change these properties on the pipe surface but not necessarily throughout the thickness of the pipe wall. Developing new methods for pipeline technical diagnosis and evaluating a line pipe’s actual technical state will help ensure the pipe's safe lifetime operation.
Sub-topic challenge– Proposals are being sought for the development of future guidance and consideration of the background factors described above. The descriptive physical model of impact strength change effect on the pipeline’s actual technical state needs to be investigated. The objective of this sub-topic is to determine the next steps after an operator determines the mechanical properties of the steel line pipe and or pipeline fittings are insufficient. Issues to specifically be considered when developing and demonstrating new non-destructive evaluation methods can/should include:
- Is hardness (other method) a good indicator for remaining strength of steel line pipe and or pipeline fittings?
- How are variable steel properties in thickness of material and at different surface locations taken into account in determining strength?
- Are some example cut-out calibration material samples required for determining uncertainties and if so at what frequency?
- What are the recommended procedures to be used and uncertainties?
- Will hardness testing be an iterative process to be conducted at various time or distance intervals?
- How does the intended methodology assess and evaluate the threat?
Proposals may consider the following attributes:
1. The variation of mechanical properties resulting from changes in the operational parameters. Long-term operating conditions in corroded pipe may lead to the degradation of stress and strain resistance capacity of the material and an increasing sensitivity to stress concentrators and defects.
2. The material steel rolling/manufacturing processes, chemical composition, any heat treatment for fittings, and strength.
3. The magnitude of critical brittle temperature, which is the temperature where the nature of a material’s fracture changes from ductile to brittle. This temperature is determined by fracture energy. It is determined by the energy used for fracture. Impact strength value is the figure of this energy. The reduction of impact strength could cause an increase of cold shortness temperature to the range of operation temperature of pipeline steels.
Expected Phase I Outcomes:
A successful Phase I will demonstrate, through mathematical models and scientific analysis, a determination as to whether hardness is a valid indicator of remaining strength for pipe and or pipeline fittings.
Expected Phase II Outcomes:
Phase II will include the validation and testing of potential models that predict the remaining strength of pipe and or pipeline fittings based on hardness or other properties.