The US Transportation Collection consists of documents from across all transportation modes with specific focus on research reports from US DOT, state DOTs, and other transportation organizations.
Bookmark this collection: https://rosap.ntl.bts.gov/collection_ust or https://doi.org/10.21949/1530857.
Flaggers maintain traffic flow through a work zone area despite a shutdown of lanes by providing temporary traffic control. In terms of occupational safety, flaggers have one of the highest risk jobs in the country, with 41 out of every 100,000 workers killed on the job each year. This project developed and tested technology for automatically detec
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Tameh, E. K., Kyong, H., Jorgensen, H., Drahos, B. A., Morris, N., & Rajamani, R. (2026). User-Centered Smart Traffic Sign Development Implementation Study (Report No. 2026-10). Minnesota. Department of Transportation. Office of Research & Innovation. https://rosap.ntl.bts.gov/view/dot/92357
Tameh, Ehsan Kazemi, Hongjoon Kyong, Helenrose Jorgensen, Bradley A. Drahos, Nichole Morris, and Rajesh Rajamani. User-Centered Smart Traffic Sign Development Implementation Study. Report no. 2026-10. Minnesota. Department of Transportation. Office of Research & Innovation, 2026. https://rosap.ntl.bts.gov/view/dot/92357.
Tameh, Ehsan Kazemi, et al. User-Centered Smart Traffic Sign Development Implementation Study. Minnesota. Department of Transportation. Office of Research & Innovation, 2026, Report no. 2026-10, ROSA P. https://rosap.ntl.bts.gov/view/dot/92357.
New U.S. regulatory targets aim for an electric vehicle (EV) market share of at least 50% by 2030, a shift mirrored by manufacturers phasing out internal combustion engine (ICE) vehicles. While public organizations are increasingly eager to transition, the pathway is complicated by cold-climate range uncertainties, infrastructure gaps in rural area
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Tork, N., Baek, K., Khani, A., Bhandari, S., & Ryan, A. (2026). Transitioning to EV Fleets: Best Practices and a Decision Tool (Report No. MN 2026-15). Minnesota. Department of Transportation. Office of Research & Innovation. https://rosap.ntl.bts.gov/view/dot/92363
Tork, Nastaran, Kwangho Baek, Alireza Khani, Sushmita Bhandari, and Alyssa Ryan. Transitioning to EV Fleets: Best Practices and a Decision Tool. Report no. MN 2026-15. Minnesota. Department of Transportation. Office of Research & Innovation, 2026. https://rosap.ntl.bts.gov/view/dot/92363.
Tork, Nastaran, et al. Transitioning to EV Fleets: Best Practices and a Decision Tool. Minnesota. Department of Transportation. Office of Research & Innovation, 2026, Report no. MN 2026-15, ROSA P. https://rosap.ntl.bts.gov/view/dot/92363.
Open-graded granular backfill materials are widely used as retaining wall backfill due to their high shear strength, high permeability, ease to handle, and compaction characteristics. However, the current Tennessee Department of Transportation (TDOT) provisions assume a conservative angle of internal friction for backfill materials. The objective o
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Alshibli, K. A., & Elkenawi, M. (2026). Evaluation of Backfill Aggregate Properties (Report No. RES2024-05). Tennessee. Department of Transportation. https://rosap.ntl.bts.gov/view/dot/89742
Alshibli, Khalid A. and Mohamed Elkenawi. Evaluation of Backfill Aggregate Properties. Report no. RES2024-05. Tennessee. Department of Transportation, 2026. https://rosap.ntl.bts.gov/view/dot/89742.
Alshibli, Khalid A., and Mohamed Elkenawi Evaluation of Backfill Aggregate Properties. Tennessee. Department of Transportation, 2026, Report no. RES2024-05, ROSA P. https://rosap.ntl.bts.gov/view/dot/89742.
Successful transportation safety messages are only effective if travelers can comprehend the notices. However, one method of safety messaging, text-only messages, can be challenging for non-native English speakers and slow-reading populations, such as older adults. The addition of graphics can potentially improve message comprehension, but their ef
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Kondyli, A., Schrock, S. D., Mahajan, K., Masud, S. S. B., Karki, A. M., Shrestha, S., & Tabatabaei, M. (2026). Creating Effective Graphic Changeable Dynamic Message Sign (DMS) Messaging (Report No. K-TRAN: KU-24-3). Kansas. Department of Transportation. Bureau of Materials and Research. https://rosap.ntl.bts.gov/view/dot/89747
Kondyli, Alexandra, Steven D. Schrock, Kirti Mahajan, Saumik Sakib Bin Masud, Aayush Maan Karki, Saurav Shrestha, and Mahgam Tabatabaei. Creating Effective Graphic Changeable Dynamic Message Sign (DMS) Messaging. Report no. K-TRAN: KU-24-3. Kansas. Department of Transportation. Bureau of Materials and Research, 2026. https://rosap.ntl.bts.gov/view/dot/89747.
Kondyli, Alexandra, et al. Creating Effective Graphic Changeable Dynamic Message Sign (DMS) Messaging. Kansas. Department of Transportation. Bureau of Materials and Research, 2026, Report no. K-TRAN: KU-24-3, ROSA P. https://rosap.ntl.bts.gov/view/dot/89747.
The primary objective of this study was to investigate the feasibility of using lignin, an environmentally friendly biopolymer, for sustainable protection of Kansas roadsides against wind and rainfall erosion during the critical stage of construction that occurs prior to the emergence of a vegetative cover. Results from laboratory-scale experiments
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Perić, D., Olia, A. S. R., & Fry, J. (2026). Use of Vegetation Enhanced by Green Soil Stabilization To Protect Kansas Roadsides From Erosion (Report No. K-TRAN: KSU-20-2). Kansas. Department of Transportation. Bureau of Materials and Research. https://rosap.ntl.bts.gov/view/dot/89761
Perić, Dunja, Arash Saeidi Rashk Olia, and Jack Fry. Use of Vegetation Enhanced by Green Soil Stabilization To Protect Kansas Roadsides From Erosion. Report no. K-TRAN: KSU-20-2. Kansas. Department of Transportation. Bureau of Materials and Research, 2026. https://rosap.ntl.bts.gov/view/dot/89761.
Perić, Dunja, et al. Use of Vegetation Enhanced by Green Soil Stabilization To Protect Kansas Roadsides From Erosion. Kansas. Department of Transportation. Bureau of Materials and Research, 2026, Report no. K-TRAN: KSU-20-2, ROSA P. https://rosap.ntl.bts.gov/view/dot/89761.
The primary objective of this study was to investigate the feasibility of using lignin, an environmentally friendly biopolymer, for sustainable protection of Kansas roadsides against wind and rainfall erosion during the critical stage of construction that occurs prior to the emergence of a vegetative cover. Results from laboratory-scale experiments
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Perić, D., Olia, A. S. R., & Fry, J. (2026). Use of Vegetation Enhanced by Green Soil Stabilization To Protect Kansas Roadsides From Erosion [Technical Summary] (Report No. KSU-20-2). Kansas. Department of Transportation. Bureau of Materials and Research. https://rosap.ntl.bts.gov/view/dot/89762
Perić, Dunja, Arash Saeidi Rashk Olia, and Jack Fry. Use of Vegetation Enhanced by Green Soil Stabilization To Protect Kansas Roadsides From Erosion [Technical Summary]. Report no. KSU-20-2. Kansas. Department of Transportation. Bureau of Materials and Research, 2026. https://rosap.ntl.bts.gov/view/dot/89762.
Perić, Dunja, et al. Use of Vegetation Enhanced by Green Soil Stabilization To Protect Kansas Roadsides From Erosion [Technical Summary]. Kansas. Department of Transportation. Bureau of Materials and Research, 2026, Report no. KSU-20-2, ROSA P. https://rosap.ntl.bts.gov/view/dot/89762.
Successful transportation messages are only effective if travelers can read and comprehend the message. However, text-based messages can be challenging for non-native English speakers or slow-reading populations, such as the elderly. The addition of graphics messages as a potential aid to improve message comprehension is uncertain, as is their effe
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Kondyli, A., Schrock, S. D., Mahajan, K., Masud, S. S. B., Karki, A. M., Shrestha, S., & Tabatabaei, M. (2026). Creating Effective Graphic Changeable Dynamic Message Sign (DMS) Messaging [Technical Summary] (Report No. KU-24-3). Kansas. Department of Transportation. Bureau of Materials and Research. https://rosap.ntl.bts.gov/view/dot/89746
Kondyli, Alexandra, Steven D. Schrock, Kirti Mahajan, Saumik Sakib Bin Masud, Aayush Maan Karki, Saurav Shrestha, and Mahgam Tabatabaei. Creating Effective Graphic Changeable Dynamic Message Sign (DMS) Messaging [Technical Summary]. Report no. KU-24-3. Kansas. Department of Transportation. Bureau of Materials and Research, 2026. https://rosap.ntl.bts.gov/view/dot/89746.
Kondyli, Alexandra, et al. Creating Effective Graphic Changeable Dynamic Message Sign (DMS) Messaging [Technical Summary]. Kansas. Department of Transportation. Bureau of Materials and Research, 2026, Report no. KU-24-3, ROSA P. https://rosap.ntl.bts.gov/view/dot/89746.
In 2018, the Virginia Department of Transportation (VDOT) implemented the American Association of State Highway and Transportation Officials' (AASHTO) AASHTOWare-ME version 2.2.6 as the pavement design methodology for new, reconstruction, and lane-widening projects, including interstate, primary, and secondary routes with annual average daily traff
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Hossain, M. S., & Nair, H. (2026). Resilient Modulus of Coarse-Grained Subgrade Soils for Pavement Design (Report No. FHWA/VTRC 26-R35). Virginia Transportation Research Council (VTRC). https://rosap.ntl.bts.gov/view/dot/89731
Hossain, M. Shabbir and Harikrishnan Nair. Resilient Modulus of Coarse-Grained Subgrade Soils for Pavement Design. Report no. FHWA/VTRC 26-R35. Virginia Transportation Research Council (VTRC), 2026. https://rosap.ntl.bts.gov/view/dot/89731.
Hossain, M. Shabbir, and Harikrishnan Nair Resilient Modulus of Coarse-Grained Subgrade Soils for Pavement Design. Virginia Transportation Research Council (VTRC), 2026, Report no. FHWA/VTRC 26-R35, ROSA P. https://rosap.ntl.bts.gov/view/dot/89731.
The development of a national standard data format for two-dimensional/three-dimensional (2D/3D) pavement surface images and Artificial Intelligence (AI) Machine Learning (ML) in Computer Vision adopted by AASHTO and embraced by state DOTs has provided TxDOT the opportunity to develop new methods for automated pavement condition assessment. This re
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Wang, F., Gong, H., Bai, Y., Tesic, J., & Luo, X. (2026). Artificial Intelligence for Pavement Condition Assessment From 2D/3D Surface Images (Report No. FHWA/TX-26-0-7150-R1). Texas Department of Transportation. Research and Technology Implementation Office. https://rosap.ntl.bts.gov/view/dot/90511
Wang, Feng, Haitao Gong, Yongsheng Bai, Jelena Tesic, and Xiaohua Luo. Artificial Intelligence for Pavement Condition Assessment From 2D/3D Surface Images. Report no. FHWA/TX-26-0-7150-R1. Texas Department of Transportation. Research and Technology Implementation Office, 2026. https://rosap.ntl.bts.gov/view/dot/90511.
Wang, Feng, et al. Artificial Intelligence for Pavement Condition Assessment From 2D/3D Surface Images. Texas Department of Transportation. Research and Technology Implementation Office, 2026, Report no. FHWA/TX-26-0-7150-R1, ROSA P. https://rosap.ntl.bts.gov/view/dot/90511.
This research investigates applying high-resolution vehicle trajectory data, derived from vehicle telematics, to facilitate freeway and arterial performance analysis in Nevada. Leveraging vehicle trajectory datasets crowd sourced through original equipment manufacturer (OEM) telematics, the research team conducted a comprehensive synthesis of commo
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Tian, Z., Wang, A., Xu, J., Campos, E. M., An, S., Xu, H., & Park, S. (2026). Freeway and Arterial Performance Analysis With High-Resolution Vehicle Trajectory Data (Report No. 500-22-803). Nevada Department of Transportation. https://rosap.ntl.bts.gov/view/dot/89820
Tian, Zong, Aobo Wang, Jianyuan Xu, Ericka Mora Campos, Siying An, Hao Xu, and Seri Park. Freeway and Arterial Performance Analysis With High-Resolution Vehicle Trajectory Data. Report no. 500-22-803. Nevada Department of Transportation, 2026. https://rosap.ntl.bts.gov/view/dot/89820.
Tian, Zong, et al. Freeway and Arterial Performance Analysis With High-Resolution Vehicle Trajectory Data. Nevada Department of Transportation, 2026, Report no. 500-22-803, ROSA P. https://rosap.ntl.bts.gov/view/dot/89820.
This study evaluated data provided by the Texas Department of Motor Vehicles (TxDMV) contained in the Texas Permitting Routing and Optimization System (TxPROS). This database includes a total of 2,122,616 OW permits spanning the 2018-2023 calendar years. More than one thousand distinct axle configurations were identified. The next step was the deve
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Prozzi, J., Inoue, D., Weissmann, A., Weissmann, J., & Glover, B. (2026). Quantify Bridge and Pavement Consumption Due to Permitted Overweight Vehicles [Project Summary Report]. University of Texas at Austin. Center for Transportation Research. https://rosap.ntl.bts.gov/view/dot/92742
Prozzi, Jorge, Danilo Inoue, Angela Weissmann, Jose Weissmann, and Brianne Glover. Quantify Bridge and Pavement Consumption Due to Permitted Overweight Vehicles [Project Summary Report]. University of Texas at Austin. Center for Transportation Research, 2026. https://rosap.ntl.bts.gov/view/dot/92742.
Prozzi, Jorge, et al. Quantify Bridge and Pavement Consumption Due to Permitted Overweight Vehicles [Project Summary Report]. University of Texas at Austin. Center for Transportation Research, 2026, ROSA P. https://rosap.ntl.bts.gov/view/dot/92742.
Highway agencies and consultants capture thousands of images during biennial, scoping, and request for action (RFA) inspections. Most of these files are stored with limited descriptions or inconsistent naming formats. As a result, a rich data source is underutilized. Understanding the value of this rich data source for asset management, MDOT initia
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Attanayake, U., Battu, N., Chun, P. j., & Weerasinghe, R. (2026). Enhance Bridge Image Attribution Through Automated Post Image Processing (Report No. SPR-1771). Michigan Department of Transportation. Research Administration. https://rosap.ntl.bts.gov/view/dot/91813
Attanayake, Upul, Naveen Battu, Pang-jo Chun, and Rajith Weerasinghe. Enhance Bridge Image Attribution Through Automated Post Image Processing. Report no. SPR-1771. Michigan Department of Transportation. Research Administration, 2026. https://rosap.ntl.bts.gov/view/dot/91813.
Attanayake, Upul, et al. Enhance Bridge Image Attribution Through Automated Post Image Processing. Michigan Department of Transportation. Research Administration, 2026, Report no. SPR-1771, ROSA P. https://rosap.ntl.bts.gov/view/dot/91813.
Temperature-induced curling and moisture-driven warping continually reshape jointed concrete pavements (JCP), altering wheel-path profiles and affecting the International Roughness Index (IRI). This report presents an integrated framework combining finite element method (FEM) analyses, artificial neural networks (ANNs), and IRI modeling to isolate
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Haider, S. W., Ahmed, H., Khazanovich, L., Lajnef, N., Lee, H., Kutay, M. E., & Cetin, B. (2026). Finite Element Method (FEM) Matrix Study for Rapid Travel Profiler Curl/Warp Correlations (Report No. SPR-1765). Michigan Department of Transportation. Research Administration. https://rosap.ntl.bts.gov/view/dot/90822
Haider, Syed Waqar, Hanan Ahmed, Lev Khazanovich, Nizar Lajnef, Hyung Lee, M. Emin Kutay, and Bora Cetin. Finite Element Method (FEM) Matrix Study for Rapid Travel Profiler Curl/Warp Correlations. Report no. SPR-1765. Michigan Department of Transportation. Research Administration, 2026. https://rosap.ntl.bts.gov/view/dot/90822.
Haider, Syed Waqar, et al. Finite Element Method (FEM) Matrix Study for Rapid Travel Profiler Curl/Warp Correlations. Michigan Department of Transportation. Research Administration, 2026, Report no. SPR-1765, ROSA P. https://rosap.ntl.bts.gov/view/dot/90822.
The quality of workmanship and adherence to specifications during the bridge construction phase of concrete decks, slabs, and continuous T-beams, are key factors on which future structural performance and durability hinge. If construction practices do not meet the required standards of quality, they may trigger early onset of deterioration processe
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Salmeron, M., Forero, O., Faiz, T., Shrivastava, K., Dyke, S. J., & Ramirez, J. A. (2026). Physics-Based Modelling of Concrete Degradation Phenomena: Impact of Construction Defects on Long Term Cost and Material Properties (Report No. FHWA/IN/JTRP-2026/14). Purdue University. Joint Transportation Research Program. https://doi.org/10.5703/1288284318622
Salmeron, Manuel, Oscar Forero, Talha Faiz, Kabir Shrivastava, Shirley J. Dyke, and Julio A. Ramirez. Physics-Based Modelling of Concrete Degradation Phenomena: Impact of Construction Defects on Long Term Cost and Material Properties. Report no. FHWA/IN/JTRP-2026/14. Purdue University. Joint Transportation Research Program, 2026. https://doi.org/10.5703/1288284318622.
Salmeron, Manuel, et al. Physics-Based Modelling of Concrete Degradation Phenomena: Impact of Construction Defects on Long Term Cost and Material Properties. Purdue University. Joint Transportation Research Program, 2026, Report no. FHWA/IN/JTRP-2026/14, ROSA P. https://doi.org/10.5703/1288284318622.
This study investigated the feasibility of using colloidal nanosilica (nS) as microstructure modifier and polymeric microspheres (MS) as alternative air-entrainment systems for Indiana Department of Transportation (INDOT) bridge deck concrete. These admixtures have gained interest due to their potential to modify the air-void system, enhance freeze
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Castillo, A., Olek, J., & Velay-Lizancos, M. (2026). Influence of Nanomaterials-Based Admixtures and Polymeric Microspheres on Entrained Air Void System and Freeze-Thaw (F/T) Resistance of Concrete (Report No. FHWA/IN/JTRP-2026/13). Purdue University. Joint Transportation Research Program. https://doi.org/10.5703/1288284318621
Castillo, Alberto, Jan Olek, and Mirian Velay-Lizancos. Influence of Nanomaterials-Based Admixtures and Polymeric Microspheres on Entrained Air Void System and Freeze-Thaw (F/T) Resistance of Concrete. Report no. FHWA/IN/JTRP-2026/13. Purdue University. Joint Transportation Research Program, 2026. https://doi.org/10.5703/1288284318621.
Castillo, Alberto, et al. Influence of Nanomaterials-Based Admixtures and Polymeric Microspheres on Entrained Air Void System and Freeze-Thaw (F/T) Resistance of Concrete. Purdue University. Joint Transportation Research Program, 2026, Report no. FHWA/IN/JTRP-2026/13, ROSA P. https://doi.org/10.5703/1288284318621.
This project advances connected vehicle applications by developing and testing an enhanced RampCast system, a comprehensive traffic management system using C-V2X technology for Indiana highways. The system features a dual-mode architecture integrating both short-range (PC5) and long-range cellular (Uu) Cellular Vehicle-to-Everything (C-V2X) communi
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Mathew, A., Sundar, A. P., Peng, J., Zhou, J., Chen, Y., & Li, F. (2026). RampCast Phase II: Connected Vehicles Traffic Management Application on Indiana Highways (Report No. FHWA/IN/JTRP-2026/11). Purdue University. Joint Transportation Research Program. https://doi.org/10.5703/1288284318619
Annual vehicle miles driven in the United States doubled, from 1.6 trillion to 3.2 trillion in the 40 years between 1983 and 2023. Unfortunately, one side effect of the increase in vehicle miles driven has been the prevalence of Animal-Vehicle Collisions (AVCs). As early as 1975, efforts began in some Western states to create safe animal passages s
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Padfield, J., & Squillace, K. (2026). Identify Bridge Design Guidelines for Wildlife Crossings (Report No. FHWA/IN/JTRP-2026/10). Purdue University. Joint Transportation Research Program. https://doi.org/10.5703/1288284318618
Padfield, Jon and Kyle Squillace. Identify Bridge Design Guidelines for Wildlife Crossings. Report no. FHWA/IN/JTRP-2026/10. Purdue University. Joint Transportation Research Program, 2026. https://doi.org/10.5703/1288284318618.
Padfield, Jon, and Kyle Squillace Identify Bridge Design Guidelines for Wildlife Crossings. Purdue University. Joint Transportation Research Program, 2026, Report no. FHWA/IN/JTRP-2026/10, ROSA P. https://doi.org/10.5703/1288284318618.
Highway roads intersect with a railroad track, forming a multimodal transportation system. The intersection is called a highway railroad grade crossing (HRGC). Because of the multiple transportation operations, induced conflict at the grade crossing, crashes may happen between road users (e.g., automobiles, pedestrians, bicyclists, etc.) and trains
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Guan, S., Chen, S., Liu, S., Noureldin, S., Burgoa, B., Shaner, A., Mouser, E., Story, P., & Stippich, K. (2026). Pedestrian and Bicyclist Trespassing Impacts on Rail Grade Crossings Safety and Mobility (Report No. FHWA/IN/JTRP-2026/09). Purdue University. Joint Transportation Research Program. https://doi.org/10.5703/1288284318617
Guan, Shanyue, Siqi Chen, Shufan Liu, Samy Noureldin, Brandon Burgoa, Alison Shaner, Elizabeth Mouser, Paige Story, and Karen Stippich. Pedestrian and Bicyclist Trespassing Impacts on Rail Grade Crossings Safety and Mobility. Report no. FHWA/IN/JTRP-2026/09. Purdue University. Joint Transportation Research Program, 2026. https://doi.org/10.5703/1288284318617.
Guan, Shanyue, et al. Pedestrian and Bicyclist Trespassing Impacts on Rail Grade Crossings Safety and Mobility. Purdue University. Joint Transportation Research Program, 2026, Report no. FHWA/IN/JTRP-2026/09, ROSA P. https://doi.org/10.5703/1288284318617.
Existing INDOT bridge projects mainly use PDF plans for the official deliverables and records to be communicated, transferred, and stored among different stakeholders. With the Industry Foundation Classes (IFC) BIM standard (ISO 16739) adopted by AASHTO as the national standard for modeling bridge projects, there comes a great opportunity to upgrad
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Zhang, J., Li, H., Akanbi, T., Hegazy, H., Yang, F., Soy, M., Chen, Y., & Dib, H. N. (2026). Integration of BIM for Bridge Modeling (Report No. FHWA/IN/JTRP-2026/08). Purdue University. Joint Transportation Research Program. https://doi.org/10.5703/1288284318616
Zhang, Jiansong, Hang Li, Temitope Akanbi, Hosam Hegazy, Fan Yang, Meta Soy, Yunfeng Chen, and Hazar Nicholas Dib. Integration of BIM for Bridge Modeling. Report no. FHWA/IN/JTRP-2026/08. Purdue University. Joint Transportation Research Program, 2026. https://doi.org/10.5703/1288284318616.
Zhang, Jiansong, et al. Integration of BIM for Bridge Modeling. Purdue University. Joint Transportation Research Program, 2026, Report no. FHWA/IN/JTRP-2026/08, ROSA P. https://doi.org/10.5703/1288284318616.
Nebraska sand-bed rivers have long been used in the development of well-known empirical bedload equations. Some of these studies have shown how adjustments in available sediment led to changes in local stream morphology. The sand-bed rivers of Nebraska are highly susceptible to such changes due to their wide, shallow cross-sections and erodibility.
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Admiraal, D., Likins, M., Wood, R., Roy, T., Pokheral, S., Nasimi, M., & Laiwal, G. A. (2026). Impacts of Stream Bed Adjustments on Local Bridge Morphology at Highway 281 (Report No. FY23(021)). Nebraska. Department of Transportation. https://rosap.ntl.bts.gov/view/dot/92541
Admiraal, David, Molly Likins, Richard Wood, Tirthankar Roy, Sudan Pokheral, Mitra Nasimi, and Gul Ahmad Laiwal. Impacts of Stream Bed Adjustments on Local Bridge Morphology at Highway 281. Report no. FY23(021). Nebraska. Department of Transportation, 2026. https://rosap.ntl.bts.gov/view/dot/92541.
Admiraal, David, et al. Impacts of Stream Bed Adjustments on Local Bridge Morphology at Highway 281. Nebraska. Department of Transportation, 2026, Report no. FY23(021), ROSA P. https://rosap.ntl.bts.gov/view/dot/92541.
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