Research Bureau

R919030 – UHPC (Phase-V) Thin-Bonded Overlay on Deteriorated Bridge Decks
Typical concrete overlay materials for existing bridge decks include latex-modified concrete, low slump dense concrete, and polyester polymer concrete. Polyester polymer concrete overlays are currently the most popular choice in New Mexico. However, the New Mexico Department of Transportation (NMDOT) has observed that polyester polymer concrete overlays are expensive and often need rehabilitation in just a few years.

Previous research has demonstrated that ultra high-performance concrete (UHPC) has the potential to increase service lives of bridge deck overlays and subsequently, the underlying concrete deck, because it has exceptional durability properties and contains silica fume that facilitates bond to substrate concretes. This research project will document, monitor, and assess the field implementation of a UHPC overlay produced with local materials on New Mexico Bridge #9706 in Socorro, NM. This will be the first non-proprietary UHPC overlay constructed in the United States.

R920040 – Study & Evaluation of Materials Response in HMA Based on Field Instrumentation Phase III
Significant changes in layer properties occur as a result of change in seasons, which dictates the stress-strain responses of pavement layers under variable field traffic loading. Collection and analysis of data from properly instrumented pavement test sections is crucial to know these strain levels to be used by the pavement designers and for understanding the actual behavior of NMDOT pavements, and hence to test the pavement materials, and model NMDOT pavement performance in the most appropriate way. Also, pavement instrumentation and in-situ testing can used to measure the impacts on overloaded truck traffic on pavement sections.
The main goal of this study is to understand the mechanisms that cause pavement failure under actual traffic loading and environmental conditions in New Mexico.  The main objective is to measure strains, stresses, deflections, moisture, and temperature to facilitate the validation of suitable response models for New Mexico pavements and thus enhancing the effectiveness or reliability of the pavement design methods.
Continued from previous phases, the main objective of Phase III research is to collect and analyze long-term field instrumentation data, including stress-strain, traffic, materials, weather, and performance, which can be used for calibration and validation of the AASHTOWare Pavement ME Design.

R920050 – Determining Effectiveness of Wildlife-Vehicle Collision Mitigation Projects Phase II
The research is aimed at estimating passage rates or relative use of crossing structures for large mammals and identify other wildlife species using crossings at constructed and planned wildlife-vehicle collision mitigation projects for a 2-3year period. In instances where fencing will be constructed during the study, we will compare use of crossing structures over time to evaluate the effectiveness of the fencing.
The specific objectives of this study are to:

• Compare wildlife passage rates or relative use of crossings with studies done in other western states.
• Identify infrastructure shortcomings or other factors that contribute to low passage rates or low relative use rates.
• Collate and review wildlife-vehicle collision and carcass collection data to determine the effectiveness of constructed projects in reducing wildlife-vehicle collisions, or at least document baseline wildlife-vehicle collision rates for planned projects.
• Create a guide for designing effective wildlife crossings and for improving existing drainage structures for mule deer (Odocoileus hemionus), elk (Cervus elaphus), black bear (Ursus americanus) and Mountain lion (Puma concolor).

R922030 – Solution to Interfacial Delamination of NMDOT’s Asphalt Pavements
To find a solution to delamination issues of New Mexico pavements, the project was initiated to identify and evaluate the following factors:

• Debonding of the tack coat from the top or bottom layer: due to poor interlayer bond caused by dissimilar material systems, improper choice of tack coat (type), lack of tack or application rate, inadequate or excessive breaking and curing of tack coat. It is worthwhile to mention here that the Department does not have acceptance or performance tests for tack coats.
• Failure within the layer: traffic- and pavement design related causes (e.g., slippage between layers due to heavy traffic, unstable or poor mix, excessive cyclic stresses at the interface of two layers)
• Damage and fracture within the interface or tack coat layer: caused by seepage of water through the surface layer, improper compaction, aging, and mismatch in thermal expansion and contraction between two layers and/or interface tack layer due to seasonal change in temperature.

R922040 – Develop a Balanced Asphalt Mixture Design Procedure
The NMDOT uses the Superpave method to design asphalt mixes which have shown poor cracking performance, although rutting performance is favorable. In a balanced mix design (BMD) approach, an asphalt mix will be designed to balance these two distresses; it will allow more rutting within a reasonable amount and reduce the long-term cracking.
The goal of this research is to develop a balanced mix design procedure, not only  considering traffic and weather conditions of a region, but also  performance driven rutting and cracking criteria.
The development of a step-by-step BMD procedure (mix volumetrics) will include multiple mix type (e.g., HMA and WMA), different performance grade (PG) binder content, aggregate gradation and type, and aging conditions.

R922050 – Conduct a Friction Testing Program, Data Analysis and Effectiveness of the NMDOT Open Grade Friction Course Program
The NMDOT conducts friction testing year-round on all state-owned roads and collected data are stored in database. There is a lack of guidance on what new roads should test at for open-graded friction course (OGFC), concrete, or chip seal, or any correlation with traffic safety, smoothness, or resurfacing criteria. Findings from this friction data focused research will be applied to pre- and post- OGFC, to determine if the friction courses are effective.

R922060 – Dust Mitigation Monitoring Project Phase II
NM DOT HSIP Dust Mitigation Projects. Since 2015, the New Mexico Department of Transportation has programmed $2.5 million in Highway Safety Improvement Program {HSIP) funds for dust mitigation activities at the Lordsburg Playa on both sides of I-10. In 2018, dust mitigation efforts in the Southern Playa {Road Forks) area were initiated including livestock exclusion, keyline plowing, printing, seeding, tackifier, and fencing. In 2020 and 2021, dust mitigation efforts in the Northern Playa area were initiated including livestock exclusion, channel/erosion control, keyline plowing, printing, seeding, tackifier and fencing. The objective of Phase II study is to determine the effectiveness of land use interventions on mitigating blowing dust and the frequency of dust-related traffic crashes

R922070 – Countermeasures to Improve Pedestrian Safety on Arterials
This project explores the most effective countermeasures to reduce pedestrian fatalities on arterial streets, using Central Avenue in Albuquerque – a pedestrian fatality hot spot – as a case study and extrapolate those results to other locations, allowing for results to not only improve traffic safety in Albuquerque, but in other municipalities across the state, region, and country. The research focuses on pedestrian safety but also addresses traffic safety outcomes for motor vehicle users and bicyclists. The treatments to be explored include a bus rapid transit (BRT) system, high intensity activated crosswalk (HAWK) beacons, turning restrictions, leading pedestrian intervals and road diets.