Research in Progress (RIP)

Aggregate Alkali-Silica-Reactivity and Mitigative Measures

Tue, 05 Aug 2025 13:32:55 GMT

Alkali-Silica-Reactivity (ASR) is a well-documented issue with aggregate used in concrete throughout New Mexico. Historically, inexpensive coal fly ash (FA), a waste byproduct of power generation with pozzolanic properties, has been relied on as an effective means of mitigating ASR. As more and more coal-fired power plants are retired and replaced by natural gas power plants and renewable energy sources, FA is no longer a reliable and readily available source of material for mitigating ASR. Natural pozzolans currently used for ASR mitigation, such as pumicite and metakaolin, are available but are costly. New Mexico has many undeveloped sources of alternative natural pozzolans which could be utilized with proper characterization and become a significant economic contribute to the state’s economy. Establishing a statewide alkali-aggregate reaction (AAR) database based on detailed ASR testing is required to provide high quality concrete with excellent long-term performance necessary for the construction of highly safe and durable concrete transportation structures. It is expected future changes to concrete specifications will reduce supply burdens and costs for quality concrete, while at the establishing local sources for alternative pozzolans, benefiting local economies, as well as concrete suppliers and customers.

Build America Buy America Requirements in Utility Relocations: A Guide for Transportation Agencies

Tue, 21 May 2024 16:07:30 GMT

The Buy America (BA) law was enacted in 1981 and modified in the Moving Ahead for Progress in the 21st Century Act (MAP-21). In 2022, the Infrastructure Investment and Jobs Act (IIJA) added the Build America Buy America Act (BABA), which expanded the list of materials required to be domestically sourced on federally funded projects. These legislative changes added requirements that impacted utility relocations on projects administered through the Federal Highway Administration. Utility companies, often operating without federal funding in their regular business practices, are not consistently familiar with the terms of BA/BABA, and procurement contracts may not expressly require BA/BABA compliance. In some cases, their interactions with state departments of transportation (DOTs) requiring BA/BABA compliance result in refusals to participate, contract, or relocate, impacting project costs and schedules. Differences in interpretation of federal BA/BABA requirements along with differences in regional laws, policies, and procedures reflect the need for additional guidance on ensuring BA/BABA compliance when working with utility companies. OBJECTIVE: The objective of this research is to develop a guide for transportation agencies to implement practices for consistently ensuring compliance with BA/BABA requirements in utility relocations.

Legal Aspects of Transit and Intermodal Transportation Programs. Topic 22-04. Update of Buy America

Mon, 04 Sep 2023 21:13:54 GMT

The Transportation Research Board (TRB) has published a series of legal guides about the federal Buy America requirements that attach to federal financial assistance provided through the U.S. Department of Transportation (U.S. DOT). TCRP LRD 17: Guide to Federal Buy America Requirements (2001) covers all the Buy America requirements, emphasizing the requirements that apply to manufactured products and rolling stock. TCRP LRD 31: Guide to Federal Buy America Requirements—2009 Supplement updates the information presented in TCRP LRD 17. TCRP LRD 49: Updated Guide to Buy America Requirements—2015 Supplement explores the varying requirements attached to funding from multiple department of transportation (DOT) modal administrations, including the Federal Transit Administration (FTA), Federal Highway Administration (FHWA), Federal Railroad Administration (FRA), Federal Aviation Administration (FAA), and the Department of Homeland Security (DHS). This digest focuses on public-private partnerships, joint development, and multimodal projects with a public transportation nexus and that receive funding from one or more federal agencies. TCRP LRD 49 also discusses the evolving Buy America rules that apply to utility relocation. Buy America practices in the U.S. DOT have evolved since the publication of TCRP LRD 49, notably with the passage and implementation of the 2021 Build America, Buy America Act (BABA), which requires iron, steel, manufactured products, and construction materials used in federally funded infrastructure projects to be produced in the United States. With cross-cutting applicability, the BABA construction materials provisions could significantly impact all federal programs. The objective of this research is to review and assess current laws, regulations, and guidance to: (1) Produce a consolidated digest that updates and supersedes TCRP LRDs 17, 31, and 49, emphasizing evolving issues, including: Reinforcement of concepts embodied in FTA’s Bob Hope Airport Intermodal Center decision concerning multiple end products within a typical construction project; Application of the construction materials requirements flowing from BABA and the Office of Management and Budget’s (OMB) August 23, 2023, guidance to federal agencies; Discussion of FTA/U.S. DOT decisions, concluding earlier FTA practices complied with BABA, except the treatment of construction materials; Implications and practices of FTA’s September 16, 2016, Dear Colleague letter allowing contractors to exercise the small purchase waiver on behalf of project sponsors; Impact of U.S. DOT’s Buy America and BABA waivers published on August 16, 2023; and The practical implications of compliance for project sponsors and contractors. (2) Produce, as an appendix to the report, a practical guide for project participants (e.g., project managers and inspectors) that captures the salient aspects of compliance and project oversight. (3) At the option of TCRP, should significant additional implementing regulations or guidance emerge during the pendency of the project or within 9 months of contract execution, provide an update incorporating the additional materials.

Reducing Greenhouse Gas Emissions from Construction of Washington Transportation Infrastructure

Thu, 27 Jan 2022 14:47:59 GMT

This research project aims to (1) benchmark greenhouse gas emissions from the construction of WSDOT’s projects based on existing specifications and sourcing practices; (2) identify needs for additional testing and research by WSDOT’s HQ Materials Laboratory based on current gaps related to decarbonization; and (3) provide recommendations on easily-implementable, cost-effective strategies for reducing WSDOT’s carbon footprint where strategies and testing already exist. The research scope will include concrete, asphalt, and steel products on the pre-approved products and vetting process for WSDOT’s qualified product list (QPL). This research will provide a first step in identifying opportunities for WSDOT to reduce greenhouse gas emissions related to construction by focusing on opportunities related to standard specifications and practices that can be implemented across WSDOT projects.

Studying the Impact of Accelerated Construction Methods in Work Zones using Micro-simulation, on Vehicle Emissions and the Environment

Thu, 30 Jul 2015 01:01:02 GMT

Pavement maintenance, repair and rehabilitation (MRR) processes may have considerable environmental impacts due to traffic disruptions associated with work zones. Several studies have been conducted to determine the lifecycle impacts of construction materials used in arterial improvement projects. But most of these studies have overlooked the mobility impact due to work zones MRR activities. According to the Texas A & M Transportation Institute Urban Mobility Report (2012) user costs due to traffic delays and additional fuel consumption have increased dramatically from $24 billion to $121 billion (in constant 2011 dollars), over the last 30 years, as a result of congestion in 498 urban areas across the country. In 2011, 56 billion pounds of additional greenhouse gases (GHG) were released just because of congestion, posing serious threats to the environment. The purpose of this study is to address the impact of work-zones on traffic and come up with a comprehensive framework to model the total emissions and its effect on storm-water runoff by simulating traffic flow around work zones. Each MRR activity requires certain traffic management plans (TMP) for example lane closure, narrowed lanes, phasing/ staging, reduced speed, detours, and ramp closure, all of which impacts the traffic flow. In previous studies, simulation models used to predict the emission of work zones were mostly static emission factor models (SEFD). SEFD calculates emissions based on average operation conditions e.g. average speed and type of vehicles. Although these models produce accurate results for large scale planning studies, they are not suitable for analyzing driving conditions at the micro level such as acceleration, deceleration, idling, cruising and queuing in a work zone. There is a need of micro-simulation analysis that can capture the effects of instantaneous changes in vehicle operation and can provide an accurate prediction of traffic and emissions for a given work zone. Increased traffic emissions not only affect air quality but also have indirect effect on water quality in the form of storm-water runoff. There are two ways in which atmospheric pollutants can enter the runoff. First, the pollutants can deposit in absence of rain under the effect of gravity, wind and turbulence and secondly, by dissolving with the water droplets during the rain. The pollutants washed away from pavements are mostly suspended solids, polycyclic aromatic hydrocarbons, and heavy metals such as Pb, Zn, Cd and Cu. The transportation of these contaminants in water can be modelled using various hydrological models. Some of popular models for storm water runoff are SWMM, HSPF, TREX, and MOUSE. These models can be integrated with traffic simulation and emission models to predict the effects of congestion, associated with work-zones, on storm-water runoff. This will provide the decision makers with a work-zone environmental assessment (WEA) framework to select suitable TMPs not only economically but also from an environmental perspective. TMPs are greatly dependent on the construction process. Accelerated construction strategies are known to have minimized construction duration and traffic disruption. Micro-simulation models can be used to calculate the change, if any, in emissions for work zones involving accelerated construction. That way the feasibility of using accelerated construction in reducing the environmental impacts of MRR activities can be determined.

Sustainable Crack-Free, Environmental-Friendly Concrete "Crack Free Eco-Crete

Wed, 20 Aug 2014 01:00:39 GMT

Since concrete is the most used construction material in the world, it accounts for a considerable part of CO2 emissions. This means that besides to its appreciable roles, it may be considered as a significant source of emission of greenhouse gases. The solution of this problem is to reduce the environmental impact of concrete and cement through the idea of Eco-Concrete. Besides to its environmental benefits, Eco-Crete is also important from the economical perspective. Because, incorporating high volumes of industrial by-products as replacements for Portland cement makes the Eco-Crete more energy efficient and cheap to produce.

Use of Adsorption Mechanism to Decrease Heavy Metal Mobility in Soil

Fri, 07 Mar 2014 01:01:41 GMT

The U.S. Food and Drug Administration has been involved in the recent food safety and beverage discussion about elevated levels of arsenic and other heavy metals in foods such as apple juice, honey and rice. Some forms of arsenic have been determined a human carcinogen by the U.S. Environmental Protection Agency (EPA), making it imperative that food quality and the associated threat to human health be studied further. Some highway construction materials such coal fly ash could be a source of these toxic elements. The environmental engineering approach to this topic is not limited to, but focuses on heavy metal (i.e. arsenic, selenium) mobility and transport in the environment, exposure and corresponding human health impacts. Missouri Science and Technology (S&T) is part of a small number of engineering institutions that are currently researching these topics. If current research trends indicate impending roles of environmental engineering, one forthcoming role will be food quality assurance. The assurance methods explored in this research includes the modification of soil chemistry and competitive adsorption states. This chemistry is based on testing the ability adsorption material (i.e. iron oxide) to fixate arsenic and other heavy metals to effectively decrease mobility and transport into the environment. This application will be tested under varying adsorbent applications to optimize adsorbent added per decreased heavy metal mobility and improve the role of environmental engineering in food quality assurance. This research is related to the Northwest University Transportation Center (NUTC) Theme #1: Advanced materials. Fly ash and other recycled construction materials could be used as novel construction materials for highway, to reduce cost, improve structure stability, and reduce carbon emission. However, heavy metals could be leached from these materials. Ultimately these heavy metals will be accumulated by crops and impact human health. While this proposed research does not directly address the strength of the construction material, it does evaluate the resulted environmental and health impact related to the application of these materials, which is part of the NUTC theme #1.

Innovative Freight Logistics Partnering in the Material Reuse Sector

Thu, 03 Jan 2013 15:41:55 GMT

New York City's Office of Long Term Planning and Sustainability issued an updated version of PlaNYC, the city's comprehensive long range plan to improve the environment and quality of life for future New Yorkers, in April 2011. Among many goals stated in the plan, the city aims to divert 75 percent of solid waste from landfills by 2030. A primary initiative identified to achieve this goal is to increase material reuse in the city. Materials that are no longer needed by individuals and businesses can be redistributed to others in need rather than placed in a landfill. Having recognized the potential for material reuse in the city, the Department of Sanitation established the New York City (NYC) WasteMatch service in 1997. WasteMatch, which is operated by the NYC Materials Exchange Development Program (MEDP) at the City College of New York, provides a web-based matching service to find potential users for donated materials. Currently, the MEDP includes 53 non-profit and for-profit partner agencies, and since its inception, WasteMatch has diverted more than 25,000 tons of material from landfills. A broad range of diverted materials include books, computers, bicycles, office furniture, and building materials. The potential for continued growth in the volume of diverted material is severely constrained by logistical challenges in transporting donated goods. Materials can only be donated for reuse if: (1) a secondary user can be identified, (2) that secondary user has available transportation resources to move a load, and (3) the secondary user can meet the sometimes strict time constraints of the donating agency to make an exchange. The transportation options available to reuse agencies vary considerably. While a few agencies have their own fleet of trucks available for goods exchange, many others with limited staff and monetary resources are required to hire commercial carriers, to rent vehicles, or even to rely on volunteer drivers to pick up donated goods. Smaller agencies, whose pick-up needs are infrequent or irregular, are often required to hire a carrier or vehicle for an individual movement at the last minute, usually at a high cost. If vehicles or drivers are not available at the necessary time, the opportunity for reuse is lost. At the same time that material reuse agencies are in need of freight capacity, there are a large number of commercial trucks operating in the city with excess capacity. According to the NYC Department of Transportation, more than 100,000 freight deliveries are made every day in Manhattan alone. Many of the trucks delivering goods to city destinations return to their origin empty, leading to inefficient operations for the carrier as well as for the city's highway network. This empty backhaul capacity could potentially be utilized to meet the needs of the material reuse sector without increasing the total volume of freight traffic on New York City's streets. The goal of this research is to explore the opportunity for innovative partnering between material reuse agencies and commercial carriers to leverage available freight capacity to enable material exchange. This project will examine potential individual or joint contracting structures to allow for more reliable freight availability to reuse agencies, as well as potential incentives to encourage commercial carriers to offer low cost or even no-cost freight transportation services to these agencies. A survey of the reuse agencies currently participating in WasteMatch will be performed to characterize the transportation needs of the reuse sector. A second survey of commercial carriers will also be performed to explore the availability of freight capacity, to identify appropriate incentives, and to examine any operational or regulatory barriers that might inhibit potential partnering structures. The transportation needs of the material reuse sector have been relatively unexplored in academic literature. This study will provide a synthesis of the state of the practice for transportation logistics in the material reuse sector and will provide an analysis of feasible alternatives for partnering between commercial carriers and material reuse agencies. Ultimately, the results of this study will serve as a source of information for cities looking to increase material reuse and as a basis for development of a pilot partnership program here in New York City.

Accelerating the Construction Process of Highway Bridges

Thu, 03 Jan 2013 15:40:35 GMT

Functional obsolescence and structural deficiencies of highway bridges are posing significant threats to commuters and transportation agencies throughout the United States. Recently, New York State Department of Transportation (NYSDOT) classified approximately one quarter of its bridges as functionally obsolete and one-eighth as structurally deficient. Highway bridges located in urban areas are especially at high risk of functional obsolescence, as the aging highway systems in these areas face significant increases in traffic volumes. As a result of increasing needs associated with upgrades and repairs, the decision makers are urged to determine the best use of limited resources. In addition to mitigating risks that emerge from ordinary operating conditions, agencies also need to determine appropriate methods to reduce the impact of natural disasters and accidents as part of an emergency response system. Employing traditional construction methods for repair or upgrade activities may cause lengthy traffic disruptions, which result in high user costs and environmental impacts, raising the issues of safety and congestion. Accelerated construction refers to project delivery methods that combine innovative construction techniques and contracting methods in order to reduce the environmental and socio-economic impacts of construction activity and to reduce the downtime of highway bridges. The objective of this study is to investigate opportunities to reduce the negative impacts of bridge closures due to repair and upgrade activities by: 1) Exploring various alternative construction materials and methods such as use of prefabricated/precast systems, and innovative contracting methods such as A+B bidding, incentive/disincentive contract, and lane rental that can be used to accelerate construction activities of bridges; 2) Identifying important factors - both qualitative and quantitative - which affect the decision-making procedures for selecting the most appropriate upgrade or repair strategy; 3). Providing a decision support framework that will allow evaluation of alternatives. In order to fulfill these objectives, a comprehensive review of the available literature will be performed with a focus on accelerated construction methods and contracts, emergency response procedures, and factors affecting decision-making procedures for selection of appropriate bridge upgrade and repair methods and contracting approaches. In addition, a national survey of state departments of transportation (DOTs) will be conducted, in order to determine the current state of practice throughout the United States. The decision support framework that will be developed in this study will provide a systematic procedure for comparing various upgrade and repair strategies; thus, decisions regarding selection of appropriate upgrade/repair methods and contracting approaches will be more objective and justifiable.

Quick Test for Percent of Deleterious Material

Thu, 03 Jan 2013 14:08:05 GMT

The Missouri Department of Transportation (MoDOT) has expressed interest in replacing its deleterious materials test method (TM 071) with something more objective. In response to a request for proposal (RFP) issued by MoDOT, it is proposed to develop a system of standard tests which would replace the deleterious test. The system would be comprised of one or more aggregate tests, depending on the outcome of the testing.

DIsmantling and RECycling Techniques for Road MATerials (DIRECT-MAT)

Thu, 03 Jan 2013 13:48:37 GMT

The greening of surface transport calls for a well-defined European strategy covering the full life cycle of road pavements. This should address issues of construction and maintenance and extend through to the end of the life cycle, via total or partial recycling and/or safe disposal. At present, many European countries have acquired experience in dismantling and recycling road materials back into roads. However, research results are not widely implemented and national documents are not often available to specialists from other countries. The DIRECT-MAT project aims to facilitate the sharing of national experiences on dismantling and recycling or safe disposal of road materials through the building of a European Web database and the drafting of Best Practice guides. Several materials are addressed - Unbound, Hydraulically bound and Asphalt road materials, but also Other materials related to road use but not commonly recycled in road construction. These include tire shreds, sediment from ditches, industrial by-products and reinforcement materials. The work program will be organized into seven work packages where four packages focus on the various construction materials (unbound, hydraulically bound, asphalt and other), one is devoted to the database and the remaining two work packages to management & coordination and dissemination. The DIRECT-MAT Web database will provide on-line access to: validated guidelines, national document references, harmonized literature reviews and practical application case studies based on jobsite data sets. Special care will be taken to reach end users at the national level and generate closer cooperation between research and practice. This is to be achieved through: cooperation with a stakeholders' panel consisting of potential end users in several countries; articles in national journals; presentations at national seminars and arrangement of a European workshop for end users in 2011.