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Full-Text Articles in Transportation Engineering

Industrial Design And Economic Analysis Of Steel Box Girder Bridge With Conventional Span, Cui Bing, Chen Kun Feb 2025

Industrial Design And Economic Analysis Of Steel Box Girder Bridge With Conventional Span, Cui Bing, Chen Kun

Journal of China & Foreign Highway

To improve the industrial construction level of steel bridges,a prefabricated continuous steel box girder bridge was designed in this study,which is suitable for bidirectional four lanes and six lanes with spans ranging from 40 m to 80 m.The overall dimensions and local structures of the steel box girder bridge were determined according to the specifications and engineering experience,and the load-bearing capacity was checked.Modular industrial products were designed by defining the vertical and horizontal modular divisions for the steel box girders,resulting in 21 standardized modular components.Based on the concept of life cycle,an economic analysis of the prefabricated steel box girder bridge …


Mechanism Of Mud Pumping On Plateau Highway Under Traffic Loads And Its Treatment Strategy, Zhang Junhui, Chen Zhide, Gao Feng, Na Qicai, Ma Pengfei, Xiao Lin Feb 2025

Mechanism Of Mud Pumping On Plateau Highway Under Traffic Loads And Its Treatment Strategy, Zhang Junhui, Chen Zhide, Gao Feng, Na Qicai, Ma Pengfei, Xiao Lin

Journal of China & Foreign Highway

The dynamic hydraulic response and particle migration of subgrade structures under traffic loads are fundamental to reveal the formation and development mechanisms of mud pumping.The driving mechanism of fine particle migration in the mud pumping state was explored by conducting laboratory tests on layered gravel-sandy silt columns under dynamic loads.The results show that the slurry sloshing causes alternating positive and negative pressure gradients within the gravel layer.This oscillating pressure gradient enhances the pore permeability in the underlying sandy silt layer,providing the necessary hydrodynamic conditions for fine particle migration.Fine particle migration increases the slurry turbidity to a stable value.Upon the removal …


Risk Zoning Of Hazards Along Highways To Xizang Based On Information Model, Liu Weimin, Guo Guanmiao, Cai Qing ’E, Yu Xueyong, Dong Xiaobo, Chen Peicong Feb 2025

Risk Zoning Of Hazards Along Highways To Xizang Based On Information Model, Liu Weimin, Guo Guanmiao, Cai Qing ’E, Yu Xueyong, Dong Xiaobo, Chen Peicong

Journal of China & Foreign Highway

The frequent occurrence of hazards along the highways in the Qinghai ‒ Xizang Plateau seriously affects road traffic and threatens the security of lives and property of the people.Conducting a risk zoning assessment of hazards along the highways to Xizang is crucial to enhancing hazard prevention and mitigation.This paper summarized the regional geological environment and development patterns of hazards along the highways to Xizang and analyzed the overall performance of highway traffic operations.On this basis,the Xinjiang‒Xizang Highway was taken as the research object,and the evaluation factors were selected based on the regional geological environment and the main controlling factors of …


Influence Of Urease-Induced Calcium Carbonate Precipitation On Frost Heave Characteristics Of Saline Soil, Li Jue, Wen Zili, Liu Zhengnan Feb 2025

Influence Of Urease-Induced Calcium Carbonate Precipitation On Frost Heave Characteristics Of Saline Soil, Li Jue, Wen Zili, Liu Zhengnan

Journal of China & Foreign Highway

This study investigated the impact of the soybean urease-induced calcium carbonate precipitation (SICP ) technique on frost heave characteristics of saline soil,specifically addressing the frost heave in saline soil used as a subgrade.The relationships between compaction degree,moisture content,volume ratio of the reaction liquid,and curing temperature with the frost heave rate of treated soil were explored.The results show that SICP significantly reduces the frost heave rate of soil samples by over 28%,with the most noticeable improvement occurring under conditions of higher compaction degree and lower moisture content.Additionally,the increased volume ratio of reaction liquid enhances reaction efficiency,while lower curing temperatures are crucial …


Prediction And Evaluation Of Road Service Performance In Cold Regions Based On Uncertainty Quantification Theory, Liu Yuanyuan, Si Junling, Zheng Hao, Ren Daoju, Fan Shaobing, Quan Lei Feb 2025

Prediction And Evaluation Of Road Service Performance In Cold Regions Based On Uncertainty Quantification Theory, Liu Yuanyuan, Si Junling, Zheng Hao, Ren Daoju, Fan Shaobing, Quan Lei

Journal of China & Foreign Highway

In cold regions,road service performance is influenced by various nonlinear dynamic factors under complex hydrothermal environments and freeze-thaw cycles.Traditional empirical and mechanical models exhibit significant limitations in comprehensively considering the impacts of complex environments and conducting quantitative analyses.This study proposed a method to predict and assess the service performance of constructed roads in cold regions.The method integrated deep neural networks with uncertainty quantification theory,addressing the inadequacies of existing models in adapting to complex environments and analyzing multiple influencing factors.By utilizing data from Montana road sections in the LTPP database,the study employed deep neural networks to predict the international roughness index …


Permanent Deformation Prediction Model Of Subgrade Soil Under Freeze-Thaw Cycles Based On Lstm And Transformer, Zhang Anshun Feb 2025

Permanent Deformation Prediction Model Of Subgrade Soil Under Freeze-Thaw Cycles Based On Lstm And Transformer, Zhang Anshun

Journal of China & Foreign Highway

To accurately predict the permanent deformation of subgrade soil under the coupling effect of freeze-thaw cycles and traffic loads,a hybrid neural network model based on long short-term memory (LSTM ) and Transformer was proposed,building upon the results of dynamic triaxial tests.This model effectively captured the temporal dependencies and complex interactive effects among input variables,thereby significantly enhancing the accuracy and generalization ability of permanent deformation prediction of subgrade soil.The results indicate that higher confining pressure improves the resistance of subgrade soil to deformation,but its permanent deformation behavior is still significantly influenced by the magnitude of cyclic loading and the number of …


Analysis Of Joint Load Transfer Performanc E Of Prefabricated Steel‑Concrete Hollow Pavement Slab, Zhu Guangshan, Dong Zihao, Yang Ye, Wang Jinshan Feb 2025

Analysis Of Joint Load Transfer Performanc E Of Prefabricated Steel‑Concrete Hollow Pavement Slab, Zhu Guangshan, Dong Zihao, Yang Ye, Wang Jinshan

Journal of China & Foreign Highway

In order to study the joint load transfer capacity of a prefabricated steel-concrete hollow pavement slab,a finite element model was established with ABAQUS to carry out numerical analysis.The variation laws of the maximum deflection value and joint load transfer coefficient of the pavement slab with and without cavitation were compared to analyze the load transfer capacity.The results show that when cavitation occurs in the slab,the load transfer coefficient of the slab decreases with the increase in the cavitation area,but the load transfer coefficient of the slab does not change significantly when the cavitation depth reaches a certain level.When there is …


A Review Of Performance Of Cement- Stabilized Base Materials Containing Recycled Conc Rete Aggregate, Song Chengzhe, Li Jiaquan, Kong Jingxun, Zhou Changjun, An Xing Feb 2025

A Review Of Performance Of Cement- Stabilized Base Materials Containing Recycled Conc Rete Aggregate, Song Chengzhe, Li Jiaquan, Kong Jingxun, Zhou Changjun, An Xing

Journal of China & Foreign Highway

Semi-rigid base offers excellent performan ce and is widely used as a high-grade highway subgrade in China.Currently,with a large stockpile of waste concrete in the country,using it as aggregate in pavement base materials is of great significance for environmental protection,energy conservation,and emission reduction.In this paper,the basic performance indicators of recycled concrete aggregate (RCA ) and the performance of cement-stabilized base materials containing RCA,including strength,shrinkage,fatigue,and erosion resistance were reviewed.It finds that the basic performance indicators of RCA are lower than those of natural aggregate.Therefore,the proportion of RCA in base materials may be limited to 20% ‒ 50%.The shrinkage and erosion resistance …


Research Progress Of Modified Asphalt With Graphene Materials, Zhang Zongwei, He Kai Feb 2025

Research Progress Of Modified Asphalt With Graphene Materials, Zhang Zongwei, He Kai

Journal of China & Foreign Highway

To clarify the research status of mo dified asphalt properties with graphene materials,relevant research literature in China and abroad was consulted to compare the effects of various graphene materials and preparation parameters on asphalt.The results show that graphene,nano graphite sheets,and oxidized graphene can improve the microstructure and road performance of asphalt,increase the service life of asphalt,and reduce the maintenance cost of asphalt.Continuously optimizing the preparation parameters of modified asphalt and exploring the mechanism of modified asphalt with new material not only help the promotion and application of new road asphalt technologies but also reduce energy consumption,pollutants,and carbon emissions,providing new ideas …


Mechanical Performance Of Nuts In Tie Rod Assembly Of Anchorage System Of Suspension Bridge, Liu Zheng, Li Zhao, Qin Guifang, Xie Qinjian, Jiang Yuangen, Zhang Jiyong, Wang Lei, Ma Yafei Feb 2025

Mechanical Performance Of Nuts In Tie Rod Assembly Of Anchorage System Of Suspension Bridge, Liu Zheng, Li Zhao, Qin Guifang, Xie Qinjian, Jiang Yuangen, Zhang Jiyong, Wang Lei, Ma Yafei

Journal of China & Foreign Highway

In order to investigate the stress and fatigue performance of nuts in the tie rod assembly of the anchorage system of a long-span suspension bridge,the finite element software Ansys and Abaqus were used to establish the full bridge model and the local finite element models of the tie rod and the hexagonal nut,respectively.Secondly,the whole process variation law of the synergistic force of the tie rod and the nut under the axial tensile load was revealed.The difference in mechanical performance between slotted nuts and unslotted nuts was compared,and the detailed structural parameters of slotted nuts were optimized.Finally,the static tensile and fatigue …


Installation Direction Design And Construction Control Of Sliding Bearing Of Continuous Girder Bridge, Guan Changlu, Sun Xiudong, Dong Hao, Wang Xingzhou Feb 2025

Installation Direction Design And Construction Control Of Sliding Bearing Of Continuous Girder Bridge, Guan Changlu, Sun Xiudong, Dong Hao, Wang Xingzhou

Journal of China & Foreign Highway

Continuous girder bridges can improve the structural stress,increase the structural bearing capacity,and promote ride comfort.However,some continuous girder bridges suffer from issues such as bearing dislocation,upper torsion,and damage to seismic arrestors.To identify deficiencies in current design and construction control,an in-depth analysis of these issues was conducted.The findings reveal the main reason is that the bidirectional sliding bearings (nearly half of the total ) fail to provide horizontal force,and the main sliding direction of the unidirectional sliding bearings is inconsistent with the deformation of the bridge superstructure.In this paper,factors including temperature-induced deformation,material shrinkage,elastic compression,creep,and construction process control of the bridge superstructure were …


Crack Propagation Of Vehicle‑Steel Bridge Deck Slabs Based On Pavement Damage, Tang Sheng, Yin Xinfeng, Zhang Ming, Yan Wanli Feb 2025

Crack Propagation Of Vehicle‑Steel Bridge Deck Slabs Based On Pavement Damage, Tang Sheng, Yin Xinfeng, Zhang Ming, Yan Wanli

Journal of China & Foreign Highway

In order to study the influence of vehicles under different pavement damage conditions on crack propagation of welded toe at the roof of steel bridge deck slabs,finite element models of suspension bridges,fine vehicles,and local steel bridge deck slabs were established,and multiple groups of obstacle heights were set to simulate pavement damage.The explicit dynamic analysis program was used to simulate vehicle-bridge coupling vibration and extract the forces of vehicles on the steel bridge deck slabs at different lanes,speeds,and obstacle heights.The crack propagation life of the welded toe at the roof was obtained by applying them to a local steel bridge deck …


Calculation Of Socket Depth For Circular Pipe Pier-Bearing Platform Socket Connection, Chen Jingli, Xiao Feng, Wang Zhigang, Wang Zhihai, Xu Yan Feb 2025

Calculation Of Socket Depth For Circular Pipe Pier-Bearing Platform Socket Connection, Chen Jingli, Xiao Feng, Wang Zhigang, Wang Zhihai, Xu Yan

Journal of China & Foreign Highway

The minimum socket depth for circular pipe pier-bearing platform socket connection can be calculated according to Article C.0.3 in the Specifications for Design of Highway Precast Concrete Bridges (JTG/T 3365 -05—2022 ).In order to enable engineering designers to fully understand and correctly apply the calculation formula in this article,this paper first introduced the main technical features of the typical connection scheme,as well as the structural failure principles and objectives formulated in the specification of the typical connection scheme.Then,it briefly introduced the experimental research content and results of the typical connection scheme and explained the key construction measures and their functions …


Reliability Analysis Of Long‑Span Concrete Box Arch Bridge Under Temperature Effect Combinations, Zheng Junlin, Jiang Youbao, Zheng Xinhao, Lu Naiwei Feb 2025

Reliability Analysis Of Long‑Span Concrete Box Arch Bridge Under Temperature Effect Combinations, Zheng Junlin, Jiang Youbao, Zheng Xinhao, Lu Naiwei

Journal of China & Foreign Highway

The existing design methods for concrete arch bridge structures do not consider the random characteristics of the eccentricity generated by load effects and overlook the influence of stochastic eccentricity on structural reliability.To address this deficiency,a calculation model for eccentricity under temperature effect combinations was derived.The random characteristics of eccentricity for different sections of the main arch of concrete arch bridges and their sectional bearing capacities were analyzed under different load parameter combinations.By utilizing the Monte Carlo method,reliability indices were computed for different sections of the main arch and different load parameter combinations after considering the random characteristics of eccentricity.The results …


Preparation And Performance Of Emulsified Asphalt With High-Temperature Resistant And Wheel Sticking-Free Effects, Yan Han, Zha Xudong, Kang Xiaogang, Gong Yan, Zhang Zhengji, Zhang Wenshuai Feb 2025

Preparation And Performance Of Emulsified Asphalt With High-Temperature Resistant And Wheel Sticking-Free Effects, Yan Han, Zha Xudong, Kang Xiaogang, Gong Yan, Zhang Zhengji, Zhang Wenshuai

Journal of China & Foreign Highway

To address the problem of wheel sticking at high temperatures in the construction process of existing wheel sticking-free emulsified asphalt of tack coat,this paper adopted the composite modification method of 70# and 15# matrix asphalt and waterborne polyurethane resin (WPR ) to prepare hard asphalt-WPR (HA-WPR )-modified emulsified asphalt in accordance with the high-temperature resistant and wheel sticking-free requirements.Through a series of laboratory tests,the technical performance,wheel sticking-free performance,and interlayer bonding performance of the emulsified asphalt were researched and compared with ordinary wheel sticking-free emulsified asphalt and ordinary emulsified asphalt tack coat oil.The results show that the technical performance of the …


Model Analysis Of Axial Compressive Mechanical Properties Of Concrete Column Constrained By Textile-Reinforced Engineered Cementitious Composites, Ma Gao, Wang Zhaoyang Feb 2025

Model Analysis Of Axial Compressive Mechanical Properties Of Concrete Column Constrained By Textile-Reinforced Engineered Cementitious Composites, Ma Gao, Wang Zhaoyang

Journal of China & Foreign Highway

In order to avoid the problem of matrix cracking in textile-reinforced concrete (TRC ),a reinforcement method of textile-reinforced engineered cementitious composites (ECC ),namely TRECC composed of textile and high-performance ECC was proposed.However,the research on the axial compressive mechanical properties of TRECC-constrained concrete in China and abroad is still insufficient,and there is a lack of reliable strength and ultimate strain analysis models.A total of 116 axial compression test results of TRC-constrained concrete columns and 125 axial compression test results of TRECC-constrained concrete columns were collected.The confinement mechanisms and failure modes of TRECC and TRC-constrained concrete were compared.Then,the strength models and ultimate …


Key Techniques For Constructing Flexible Geosynthetic Reinforced Soil Abutments, Yu Xiaoxiao, Xu Chao, Li Haoyu, Zuo Binli Feb 2025

Key Techniques For Constructing Flexible Geosynthetic Reinforced Soil Abutments, Yu Xiaoxiao, Xu Chao, Li Haoyu, Zuo Binli

Journal of China & Foreign Highway

The flexible geosynthetic reinforced soil (GRS ) abutments offer several advantages,including cost saving,reduced bridgehead misalignment,and good seismic performance,showing great potential for application in transportation engineering both in China and abroad.The flexible GRS abutment is essentially composed of a composite structure formed by closely spaced layers of geosynthetic reinforcement material,and the construction quality and load-bearing capacity are crucial to the success of the project.To ensure construction quality and study the construction process of flexible GRS abutments,a construction site monitoring method was adopted.Based on the experience from the construction of a vehicular overpass on the Wuwei ‒ Yuexi Expressway,the quality control measures …


Research On Mechanical Entry Excavation And Reinforcement Measures For Large Cross-Section Tunnel, Liang Xiao, Li Ke, Guo Hongyan, Hu Xuebing, Yao Chengrui Feb 2025

Research On Mechanical Entry Excavation And Reinforcement Measures For Large Cross-Section Tunnel, Liang Xiao, Li Ke, Guo Hongyan, Hu Xuebing, Yao Chengrui

Journal of China & Foreign Highway

With the innovation of tunnel construction techniques and mechanical equipment,mechanical drilling and blasting for mountain tunnels have gradually developed.However,several challenges exist during the mechanical entry excavation for mountain tunnels,including the significant influence of geological factors,limited equipment adaptability,and constrained working space.This research,based on a specific tunnel project,utilized FLAC3D finite difference software to study the mechanical excavation method and auxiliary reinforcement measures for shallow-buried segments at the large cross-section tunnel portal.A comparative analysis was conducted on the displacement of surrounding rock,the stress of supporting structures,and the variation of plastic zones before and after tunnel face reinforcement for different advances per cycle and …


Application Research Of Bim Technology In Highway Prefabricated Bridge Scheme Design, Li Jinlong, Wang Xinnan, Liu Dongsheng, Chen Zhongzhi Feb 2025

Application Research Of Bim Technology In Highway Prefabricated Bridge Scheme Design, Li Jinlong, Wang Xinnan, Liu Dongsheng, Chen Zhongzhi

Journal of China & Foreign Highway

At present,the highway bridge scheme requires continuous adjustments and upgrading due to iterative updates of design data and refined investigation of the surrounding environment of the bridge site.This paper upgraded the traditional route design software,developed a GIS-integrated platform,built a three-dimensional environment with design data as the core,and created a bridge scheme model through parametric intelligent design.It also evaluated and optimized the bridge scheme based on the integration of the bridge model and the surrounding environment.The results show that by using BIM technology,the forward design of a bridge scheme based on a three-dimensional environment is realized.This approach automates the scale statistics …


Estimating Depth Of Roadway Flooding Using Data From Lidar And Surveillance Cameras, Mahta Zamanizadeh, Mecit Cetin Feb 2025

Estimating Depth Of Roadway Flooding Using Data From Lidar And Surveillance Cameras, Mahta Zamanizadeh, Mecit Cetin

Graduate Student Government Association Research Conference

In this study, we fuse data from a 3D LIDAR mounted on a vehicle and images from an external traffic surveillance camera to create a 3D representation of a segment of a roadway that experiences frequent flooding. The point cloud data from the LiDAR in this study is collected from a road segment of W 49th Street in Norfolk, near the ODU campus. The traffic surveillance camera is mounted on a public parking building in the same area. The LiDAR collects continuous point cloud frames as the vehicle traverses the section. Multiple LIDAR frames related to the respective segment …


Application Of Cementitious Materials And Fiber Reinforcement To Enhance Lime Stabilization For Nebraska Shale Soils, Jongwan Eun, Seunghee Kim, Chung R. Song, Laith Ibdah, Kenaz Owusu Feb 2025

Application Of Cementitious Materials And Fiber Reinforcement To Enhance Lime Stabilization For Nebraska Shale Soils, Jongwan Eun, Seunghee Kim, Chung R. Song, Laith Ibdah, Kenaz Owusu

Nebraska Department of Transportation: Research Reports

Lime stabilization is a widely used technique to improve weak subgrades; however, its effectiveness under freeze-thaw cycles remains a critical challenge. This study investigates the incorporation of cementitious materials and fiber to enhance the mechanical properties and environmental resistance of lime-stabilized soils under such conditions. Two types of soil, gray shale (plasticity index of 37.8) and clay soil (plasticity index of 19.0) from Nebraska, were used. Stabilization mixtures included lime dosages of 0%, 3%, and 6% by weight, combined with either 10% fly ash or 3% and 6% cement by weight, and 0% and 1% fiber. The experimental program comprised …


Current Practices In Rock Scaling, Daryl J. Greer, Kean H. Ashurst Jr Feb 2025

Current Practices In Rock Scaling, Daryl J. Greer, Kean H. Ashurst Jr

Kentucky Transportation Center Research Report

Rockfalls, which result from the chemical and physical weathering of aging exposed rock cuts, occur frequently along many Kentucky roadways and can endanger travelers. Mitigating rockfalls often requires substantial excavation, procuring additional right of way, and/or hiring specialty contractors. An alternative to these expensive processes is rock scaling, which can be a cost-effective tool for mitigating rockfalls. Rock scaling entails removing loose and unstable rocks from rock cut slopes within the right of way to reduce rockfall risk and is being used with increased frequency by state transportation agencies around the country. The Kentucky Transportation Cabinet (KYTC) has completed several …


Bridge Load Posting Based On Load Testing, Cody Hutchinson, Abheetha Peiris, Issam Harik Feb 2025

Bridge Load Posting Based On Load Testing, Cody Hutchinson, Abheetha Peiris, Issam Harik

Kentucky Transportation Center Research Report

AASHTO’s Manual for Bridge Evaluation (MBE) provides guidance for analytically evaluating bridge capacity based on available design information and the results of field inspections. This analysis results in a rating factor (RF), which quantifies a bridge’s safe load carrying capacity. RF accuracy, however, depends on the availability of information about structural details and material properties. As such, load rating bridges without design plans is difficult as field inspections alone often cannot provide enough information to perform detailed analysis. In many instances this means that a bridge would possess a substandard rating factor (RF < 1.0) simply due to the conservative assumptions required to perform traditional analysis. The most effective method for safely modifying such conservative theoretical rating factors is through load testing. Load testing measures actual bridge behavior and, for most bridges in good health, finds an increase in load rating is justified. This project utilized load testing to load rate 14 bridges in Kentucky that lack structural plans. Researchers first determined theoretical ratings using MBE-prescribed methods. For information typically taken from design plans, but which could not be measured directly, data-backed methods for making conservative assumptions were developed. For most bridges included in the study, theoretical rating factors alone suggested load postings were necessary. Load testing was then carried out utilizing tandem rear-axle dump trucks with measured axle weights. Multiple single-lane load cases were selected to maximize the effects being rated. Strain data were collected in real time using a wireless reusable strain gage system. Using these data, researchers computed a field test adjustment factor using MBE methods which directly modified the calculated theoretical RFs. Ultimately, load testing provided sufficient evidence to safely recommend that load postings were not necessary for any bridges in this study.


Effect Of Shrinkage-Mitigating Materials, Fiber Type, And Repair Thickness On Flexural Behavior Of Beams Repaired With Fiber-Reinforced Self-Consolidating Concrete, Jingjie Wei, Kamal H. Khayat Feb 2025

Effect Of Shrinkage-Mitigating Materials, Fiber Type, And Repair Thickness On Flexural Behavior Of Beams Repaired With Fiber-Reinforced Self-Consolidating Concrete, Jingjie Wei, Kamal H. Khayat

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

While self-consolidating concrete (SCC) has emerged as a highly effective approach for the repair of concrete structures, there have been few investigations regarding the effect of the combination of different fiber and shrinkage-mitigating material types (shrinkage-reducing admixture, SRA; superabsorbent polymer, SAP; and expansive agent, EA) on the flexural behavior of repaired structures. This study aims to explore the influence of three different shrinkage-mitigating materials (1.25%–2.5 % SRA, 4%–8% EA, and 0.2%–0.4 % SAP), four fiber types (two macro synthetic fibers, MSFA and MSFB; 5D hooked steel fibers, 5D; a combination of 80 % 3D hooked steel +20 % short steel …


Application Of Cementitious Materials And Fiber Reinforcement To Enhance Lime Stabilization For Nebraska Shale Soils, Jongwan Eun, Seunghee Kim, Chung R. Song, Laith Ibdah, Kenaz Owusu Feb 2025

Application Of Cementitious Materials And Fiber Reinforcement To Enhance Lime Stabilization For Nebraska Shale Soils, Jongwan Eun, Seunghee Kim, Chung R. Song, Laith Ibdah, Kenaz Owusu

Nebraska Department of Transportation: Research Reports

Lime stabilization is a widely used technique to improve weak subgrades; however, its effectiveness under freeze-thaw cycles remains a critical challenge. This study investigates the incorporation of cementitious materials and fiber to enhance the mechanical properties and environmental resistance of lime-stabilized soils under such conditions. Two types of soil, gray shale (plasticity index of 37.8) and clay soil (plasticity index of 19.0) from Nebraska, were used. Stabilization mixtures included lime dosages of 0%, 3%, and 6% by weight, combined with either 10% fly ash or 3% and 6% cement by weight, and 0% and 1% fiber. The experimental program comprised …


Draft Active Travel & Public Realm Evaluation Framework (Summary), Sarah Rock Dr, Sinead Flavin Jan 2025

Draft Active Travel & Public Realm Evaluation Framework (Summary), Sarah Rock Dr, Sinead Flavin

Other Resources

This aim of this Draft Summary Framework is to assist Local Authorities & other similar authorities in the monitoring and evaluation of their active travel & public realm interventions. It is intended to allow for flexibility depending on the project objectives and context, and is not intended to be a definitive list of indicators and metrics. The indicators and metrics included seek to strike the balance between what's reasonable, practical and feasible for a Local Authority and associated resources in terms of monitoring & evaluation. Not all projects can be reasonably expected to be fully monitored and evaluated, thus a …


Hydrogen-Enriched Lng As A Mid-Term Solution To Mitigate Greenhouse Gas Emissions From Shipping, Kang-Ki Lee Jan 2025

Hydrogen-Enriched Lng As A Mid-Term Solution To Mitigate Greenhouse Gas Emissions From Shipping, Kang-Ki Lee

World Maritime University Ph.D. Dissertations

In light of the International Maritime Organization’s (IMO) ambitious Initial GHG Strategy, the rise in international shipping’s carbon dioxide emissions by 2 percent in 2022 compared to 2019 poses a formidable challenge. This increase underscores the pressing need to address the limited availability of green hydrogen, prompting the exploration of mid-term solutions to bridge this critical gap. The IMO’s 2023 Strategy on Reduction of GHG Emissions from Ships attempted to tackle this challenge head-on, recognizing the urgency of reducing the industry’s substantial carbon footprint. While hydrogen offers a simple solution as a zero-carbon fuel, LNG remains the most widespread alternative …


Flexural Post-Cracking Performance Of Macro Synthetic Fiber Reinforced Super Workable Concrete Influenced By Shrinkage-Reducing Admixture, Jingjie Wei, Nima Farzadnia, Kamal H. Khayat Jan 2025

Flexural Post-Cracking Performance Of Macro Synthetic Fiber Reinforced Super Workable Concrete Influenced By Shrinkage-Reducing Admixture, Jingjie Wei, Nima Farzadnia, Kamal H. Khayat

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Most literature has focused on the effect of shrinkage-reducing admixture (SRA) in shrinkage mitigation resistance of concrete. This study aims to examine the impact of SRA on the efficiency of macro synthetic fibers (MSF) in enhancing the flexural post-cracking behavior of fiber-reinforced super workable concrete (FR-SWC). A comparative analysis of the influence of fiber combinations on the flexural post-cracking behavior of beams is also included. Results showed that a higher dosage of SRA, particularly at 5 % by mass of binder, had a noticeable negative impact on flexural post-cracking performance of beams while exhibiting positive effect on workability and shrinkage …


Proactive Distributed Emergency Response With Heterogeneous Tasks Allocation, Justice Darko, Hyoshin Park Jan 2025

Proactive Distributed Emergency Response With Heterogeneous Tasks Allocation, Justice Darko, Hyoshin Park

Engineering Management & Systems Engineering Faculty Publications

Traditionally, traffic incident management (TIM) programs coordinate the deployment of emergency resources to immediate incident requests without accommodating the interdependencies on incident evolutions in the environment. However, ignoring these inherent interdependencies while making current deployment decisions is shortsighted, and the resulting naive deployment strategy can significantly worsen the overall incident delay impact on the network. The interdependencies on incident evolution in the environment, including those between incident occurrences and those between resource availability in near-future requests and the anticipated duration of the immediate incident request, should be considered through a look-ahead model when making current-stage deployment decisions. This study develops …


Accelerated Test Method (Atm) For The Evaluation Of External Sulfate And Chloride Attack On Concrete Using Artificial Climate Environment (Ace): An Assessment Of Methodology, Eli Walker Jan 2025

Accelerated Test Method (Atm) For The Evaluation Of External Sulfate And Chloride Attack On Concrete Using Artificial Climate Environment (Ace): An Assessment Of Methodology, Eli Walker

College of Graduate Studies: Theses & Dissertations

This study seeks to investigate a testing methodology that utilizes accelerated testing methods (ATM) in conjunction with nondestructive testing methods (NDT) to assess destructive ion attacks on concrete. Through the testing of concrete samples, the impacts of chloride and sulfate ions on concrete will be tested by subjecting concrete to cyclic testing in an artificial climate environment. Electrical resistivity (ER) and ultrasonic pulse velocity (UPV) testing will evaluate the impact of the accelerated testing on the migration of destructive ions within the pore structure of the tested concrete. Based on this investigation, comparisons between accelerated, non-accelerated, and control samples will …