Engineering Commons^™

The Game Of Traffic Lights (Tgotl), Faith Chapman

Posters - 2024

“Computer Science can be applied to nearly ANY field.” In college, and high school especially, the phrase is just that—early comp. sci (CS) students don’t have realworld examples of how/where else they can use CS knowledge outside of CS focused jobs. For high school students, this a missed opportunity to plan for a career outside the obvious. One such career is in traffic lights.

U.S. traffic can be better. Engineering has a subfield dedicated to improving traffic, and part of that entails studying ways to improve traffic lights’ efficacy. Someone with CS knowledge can program a traffic simulator for data …

Advancing Data-Driven Decision Making For Transportation Safety: Emerging Trends, Statistical Modeling, And Causal Inference, Guocong Zhai

Civil & Environmental Engineering Theses & Dissertations

Despite recent advances in data-driven decision-making for transportation safety, there remain potential biases in the decision-making for emerging trends (i.e., shared mobility, safe systems, vehicle electrification, and equity) in transportation. In that case, this dissertation aims to facilitate robust and equitable data-driven decision-making in transportation safety, addressing the potential biases: 1) spatial and inherent correlations across different types of crashes, 2) measurement error biases of exposures, 3) confounding biases, and 4) disparity biases in transportation safety.

To be more specific, four research objectives are demonstrated below. Chapter 3 assessed the safety performance of taxi and ride-hailing services by a multivariate …

Modeling The Impact Of Connected And Automated Vehicles On Driving Behaviors And Safety: A Driving Simulator Study, Abdalziz Alruwaili

Civil & Environmental Engineering Theses & Dissertations

Connected vehicles (CVs), equipped with advanced sensors, can communicate safety messages to drivers. Automated vehicles (AVs), designed with the ability to automate safety critical control functions, will redefine the traditional role of drivers. This dissertation aims to investigate the impact of connected and automated vehicles (CAVs) on driving behaviors and safety outcomes using data from driving simulator experiments. More specifically, the research objectives include:

1. Modeling the impacts of CVs on driving aggressiveness and situational awareness in highway crash scenarios.

2. Modeling the impacts of CV technologies on driving behaviors and safety outcomes in highway crash scenarios under diverse weather …

Safety Evaluation Of Hawaii Dot Modified Type A-1 Flared Buried In Backslope Guardrail End Terminal, Sina Changizian

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

The Hawaii Department of Transportation (HDOT) desired to evaluate the crashworthiness of a guardrail end terminal design in which the upstream guardrail anchorage was connected to a block partially buried in a cut slope, known as a “Buried in Backslope” or BIB design. The HDOT BIB system used an upper W-beam with 8-in. deep blockouts attached to W6x9 steel posts and a lower W-beam rubrail located 3 in. below the upper rail. The system used two horizontal flares: 7.4:1 near the upstream anchor block and a 13:1 flare through the ditch.

Critical impact points (CIPs) were identified and recommended for …

Modelling Techniques For Slab Track Systems, Mohamed Hafez Fahmy Aly, Islam Mahmoud Abou El-Naga, Ahmed Abdul Hay Soliman, Muhammad Ahmad Diab

Journal of Engineering Research

The railway slab track has replaced the ballast material in the classical ballasted track with reinforced concrete slab or asphalt layer to cope up with the increasing axle loads, train high-speeds, and to reduce overall maintenance cost. This paper aims to investigate the linear and nonlinear behavior of the most common slab track systems (BÖGL, Shinkansen, and RHEDA 2000) using American (AREMA) loads for different soil types to recommend the most suitable analysis type for each component of the slab track systems. Slab track Finite Element models have been built using Midas GTS NX software. The geometric model for each …

Use Of Waste Plastics In Asphalt Mixes: Addressing The Variability Of Source, Venkatsushanth Revelli, Anil Kumar Baditha

Graduate Student and Postdoctoral Fellow Symposium

Use of waste plastics in asphalt mixtures suffers from a serious problem of significant variability with global sources; preventing proper guidelines for field applications. The aim of this study is to address the variability in source of waste plastic and its impact on asphalt mixture design. The study was designed to provide a selection criterion to evaluate the suitability of waste polyethylene (PE) for asphalt pavements. PE obtained from five sources was used as a replacement for asphalt binder. Dry mixing of plastics with asphalt and aggregate was performed at the dosage levels of 3%, 6%, and 9%. The changes …

Performance Assessment Of Microencapsulated Phase Change Materials With Low To High Thermoregulation Range In Asphalt Binder, Anil Kumar Baditha, Ayyaz Fareed

Graduate Student and Postdoctoral Fellow Symposium

Asphalt pavements face significant challenges due to low temperature cracking and rutting caused by extreme temperature fluctuations and traffic loading. These issues result in higher maintenance costs and reduced service life of the pavements. To address this, researchers explored the use of Microencapsulated Phase Change Materials (MPCMs) to induce thermoregulation in asphalt pavements. However, the existing research focused on high-temperature performance of binders, highlighting the need of research on evaluating the low-temperature performance. Therefore, the study aims to evaluate the impact of incorporating MPCMs on low to high temperature performance of binders. Three types of MPCMs were incorporated into asphalt …

Safety Investigation Of Crash Rates During Hurricane Evacuations, Amelia K. Lawson

Doctoral Dissertations and Master's Theses

This study aimed to investigate crash rates across four distinct periods—evacuation, re-entry, emergency, and non-emergency—during Hurricanes Matthew (2016), Irma (2017), and Michael (2018). A notable gap in existing research pertains to understanding crash rates during these critical phases of hurricane events. By addressing this gap, this research contributes to a deeper comprehension of evacuation transportation safety. The methodology employed ArcMap to construct an interactive map for data collection, encompassing key variables such as the number of crashes, traffic volumes, duration of each period under analysis, and roadway segment lengths for each hurricane. Evaluating the crash rate per million vehicular miles …

Key Construction Techniques For Incremental Launching And High Falling Beam Of Long‑Span Simply Supported Steel Box Girder, Wu Yanbin, Lyu Maofeng, Yin Qijia, Yu Guanqiu

Journal of China & Foreign Highway

Based on the overpass project over Beijing-Hong Kong-Macao Expressway on Changsha Pan-Pan Road，this paper proposed a construction method of large-slope walking-type incremental launching and high falling beam of steel box girder given the difficulties in busy traffic under the bridge，large pushing slope，and great total height of falling beam.After the steel box girder assembly was completed，some bridge deck ancillary facilities were constructed in advance in the preassembly yard and the weight was allocated.The steel box girder was pushed synchronously，thereby reducing the aerial work on the bridge in the later stage.During the incremental launching construction of the steel box girder above the …

Different Forms Of Nano‑Sio2 In Emulsified Asphalt And Their Effects On Emulsion Storage Stability, Ji Chao, Cao Yuanhao, Li Zhigang

Journal of China & Foreign Highway

The insufficient storage performance of emulsified asphalt has always been a problem affecting its application，and there have been studies in China on nano-SiO2 particles as additives to improve the stability of emulsified asphalt，but the effect is not obvious.Based on the principle of Pickering emulsion，nano-SiO2 with surface modification was used as an emulsifier to directly emulsify matrix asphalt，and whether its stability improvement effect on emulsified asphalt is better than nano-SiO2 as a modified additive was explored.Firstly，three emulsified asphalt were prepared，namely ordinary modified emulsified asphalt A，emulsified asphalt B with nano-SiO2 as a modified additive，and emulsified asphalt C based on the new nano-SiO2 …

Study On Test Methods Of Wheel Sticking‑Free Emulsified Asphalt, Wang Peng, Qin Yongchun, Wang Jie, Xiong Weiming, Chang Rong, Fu Chongfeng, Feng Guoli

Journal of China & Foreign Highway

The wheel sticking-free emulsified asphalt is a key material to solve the wheel sticking problem in the process of asphalt pavement construction，with the wheel sticking-free effect as the core index.The accurate evaluation of the wheel sticking-free effect is important for the popularization and application of wheel sticking-free emulsified asphalt.Based on the research results in China and abroad，two test methods for wheel sticking-free effects （counterweight method and indenter method ） were innovatively proposed，and the wheel sticking-free effects of various emulsified asphalt were evaluated.The test results show that the two test methods can accurately evaluate the wheel sticking-free performance of emulsified asphalt，and …

Study On Mobilization Rate Of Rap Aged Asphalt Based On Ftir, Zou Xiaoyong, Li Ning, Wu Wenxiu, Wang Xin, Xu Xiaohe

Journal of China & Foreign Highway

During the preparation of the recycled asphalt mixture，part of the aged asphalt is first transferred from the surface of the recycled material to the new aggregate and then diffused and fused with the new asphalt，in which the percentage of transferred aged asphalt plays a key role in the final regeneration effect.In order to study the degree of transfer of aged asphalt in reclaimed asphalt pavement （RAP ），the mobilization rate （RMR） was calculated and analyzed based on the Fourier transform infrared spectroscopy （FTIR ）.The AC-13 graded recycled asphalt mixture was mixed and sieved to separate the new aggregate and RAP.The recycled …

Deflection Variation Rule Of Main Girder For A Concrete Cable‑Stayed Bridge Based On Combined Static And Dynamic Modification, Li Qi, Qi D Ongchun, Yang Hu, Zhao Zhiguo

Journal of China & Foreign Highway

In order to solve the problem of continuous downward deflection of the main girder for a concrete cable-stayed bridge during its service life，the deflection variation of the main girder for a long-span concrete cable-stayed bridge during its service was analyzed based on the modified model.A dual-objective optimization problem was constructed by using the combined static and dynamic finite element model modification method and was solved by the non-dominated sorting genetic algorithm （NSGA- Ⅱ）.The Pareto optimal solution set was obtained，and the coordinated optimal solution was found in the Pareto optimal solution set，so as to modify the finite element model.The calculated values …

Construction Technology Of Reactive Powder Concrete Prestressed Box Girder, Wang Xiaojie

Journal of China & Foreign Highway

At present，high-strength and high-performance concrete has some disadvantages，such as low flexural strength，large brittleness，and poor volume stability.Reactive powder concrete （RPC ） is a new type of material，which has good mechanical properties and high impermeability.It can reduce the amount of concrete to a greater extent and reduce the weight of the structure，achieving the purpose of safety，reliability，and cost saving.This paper applied RPC to highway prestressed box girder.Through the innovation and optimization of mix ratio，the change in traditional transportation technology，and curing technology research of steam curing shed，it effectively shortens the pouring time of RPC，ensuring the pouring quality and strength.

Fragilit Y Analysis Of Continuous Rigid Frame Bridge With High Piers And Long Span Subjected To Near‑Field Earthquakes, Sun Yongjiang

Journal of China & Foreign Highway

Near-field earthquakes are more destructive to the continuous rigid frame bridge with high piers and long span.Based on a new-built continuous rigid frame bridge with high piers and long span，considering the seismic demand probability of bridges under near-field earthquakes，this paper utilized OpenSees to analyze the time history of the bridge.The structure response of the bridge under near-field earthquakes was obtained by the nephogram method，and the vulnerability of the bridge under earthquake was analyzed based on the curvature demand probability model of the structure.The results show that the probability response of curvature demand of a continuous rigid frame bridge with high …

Lightweight Replacement Technology For Existing Soft Subgrade Based On Over‑Consolidated State, Huang Baotao, Zhang Mudan, Huang Xiangshuo, Fang Mingshan, Feng Jianxue, Huang Lizhen

Journal of China & Foreign Highway

In order to solve the differential settlement of soft subgrade in coastal areas，based on the elastic deformation theory of overconsolidation stress ratio，the calculation and analysis of artificial overconsolidation stress ratio and the new technology of lightweight replacement were carried out to reduce the additional stress of vehicle load and structure weigh.The results show that the replacement thickness of the lightweight material with suitable density can make the additional stress at the bottom of the subgrade less than the deadweight stress of the original soft soil，and the additional stress is less than the initial flow stress of the soft soil.The resulting …

Analysis Of Stress And Drainage Characteristics Of Water Film Between Tire And Road Surface And Influence Of Groove Parameters, Sun Zhenhao, Chen Jun

Journal of China & Foreign Highway

In order to study the stress characterist ics of water film on cement concrete road surface under the action of the tire and the influence of grooves，the finite element model of tire-water film-road surface was constructed using SolidWorks and Ansys Workbench.Based on computational fluid dynamics （CFD ） control equation and fluid-structure coupling theory，the flow law of water film on road surface under the action of the tire and the influence of water film thickness，driving speed，groove width，groove spacing，and groove direction on the hydrodynamic lift of tire were analyzed.The results show that the hydrodynamic lift of the tire increases with the increasing …

Influence Of Rap Content On Mechanical Properties And Pavement Performance Of Warm Recycled Asphalt Mixture, Ren Ruibo, Yin Liyang, Xu Qiang, Zhao Pinhui, Ma Shidong

Journal of China & Foreign Highway

Warm recycling technology is an effective new technology for recycling recycled asphalt pavement （RAP ）.In order to improve the pavement performance of warm recycled asphalt and effectively enhance the recycling rate of RAP，the influence of RAP content on the performance of warm recycled asphalt mixture was investigated through mechanical properties and pavement performance analysis，and the correlation between dynamic stability and mechanical parameters of creep tests under repeated loading was discussed.The results show that with the increase in RAP content，the high-temperature stability，shear resistance，and elastic deformation resistance of warm recycled asphalt mixture are improved，but the low-temperature crack resistance and water stability are …

Expressway Traffic Flow Prediction Based On Data From Multiple Related Toll Stations, Zhang Yang, Yao Fangyu, Yang Shumin

Journal of China & Foreign Highway

The strong inter-economic connection makes a spatial correlation between traffic data from multiple related toll stations between urban cluster regions，and an accurate description of this connection can improve the accuracy of expressway traffic flow prediction.However，due to many uncertainties，the correlation is difficult to be captured and quantified.To solve this problem，an ATGCN-ResGRU deep learning-based expressway traffic flow prediction method was proposed.By combining attention mechanisms，three graph convolutional networks （GCN ） topological networks with high，medium，and low attention levels were constructed，and spatial learning data was obtained according to the weighted attention level of each network.The connection of multiple related toll stations was quantified and graded.At …

Carbon Emission Calculation And Scheme Selection For Roadbed Drainage Ditches By Mechanized Construction, Xing Hao, Wu Jiarun, Li Han, Lin Yuliang, Guo Dongdong

Journal of China & Foreign Highway

Aligned with the peak carbon and neutrality goals，the mechanized construction of roadbed drainage ditches should consider not only construction efficiency and economic factors but also carbon emissions.This study，centered on the Meng-LYU highway，devised approaches to calculate roadbed drainage ditches' carbon emissions and investment costs across three stages：building material production，transportation，and construction.By introducing the concept of carbon trading to align carbon emissions and investment costs，a comprehensive comparison was conducted between the conventional supporting formwork method and the hydraulically powered sliding formwork method regarding equivalent carbon emissions.An orthogonal experiment was conducted involving the upper length of the roadbed drainage ditch，pouring thickness，haul distance，and construction length …

Study On Treatment Method Of Expansive Soil Embankment In Expressway Reconstruction And Extension, Wang Yuwei, Hu Yanli, Zhang Rui

Journal of China & Foreign Highway

In order to fully utilize expansive soil as filler in highway reconstruction and expansion projects，this paper draws on the successful experience of using expansive soil directly in road construction.It proposes an embankment treatment scheme that involves the use of geogrid-reinforced expansive soil with edge wrapping，based on the reconstruction and expansion project of the Hefei to Dagudian section of the G 40 Shanghai-Shaanxi Expressway.Through laboratory tests，the road performance and swelling characteristics of the expansive soil filler were investigated to determine the applicable scope and compaction control indices of the filler.Then，the feasibility of the embankment treatment scheme was demonstrated through the prediction …

Prediction Method Of Surrounding Rock Deformation Of Highway Tunnels Based On Bayes‑Lstm, Liu Zhi, Li Xinyu, Li Zhen, Kong Xianguang, Chang Jiantao

Journal of China & Foreign Highway

In the process of highway tunnel construction，the stability of surrounding rock has a great impact on tunnel construction.Therefore，the monitoring measurement and accurate prediction of surrounding rock deformation of highway tunnels are the keys to ensuring the safety of tunnel construction.In view of the low prediction accuracy and poor generalization ability of tunnel surrounding rock deformation，this paper proposed a Bayesian （Bayes ）-based method to optimize the long-term and short-term memory （LSTM ） network.The method first preprocessed the original monitoring data of crown settlement and peripheral convergence，then constructed the initial LSTM model of crown settlement and peripheral convergence of highway tunnels，and used …

Comparative Analysis Of Test Results Of Different Nano‑Clay Improved Loess, Zhao Danni, Cao Baohua, Xu Jiangbo, Nan Yalin, Chen Nengyuan, Zhang Peng, Wang Heping

Journal of China & Foreign Highway

The orthogonal design t est was used to quantitatively analyze the influencing factors and influence degree of compressive strength，shear strength index，and permeability coefficient of improved loess，and the optimal content of improved loess was obtained.In addition，the improvement mechanism of nano-clay materials on loess was explored by scanning electron microscopy.The results show that：① The factors affecting the compressive strength of improved loess are the content of nano-clay，water content，and curing age，and the factors affecting cohesion，internal friction angle，and permeability coefficient are the content，dry density，and confining pressure.② Under different influencing factors，nano-montmorillonite can effectively improve the compressive strength of loess than attapulgite.③ When the material content …

Technical Essentials Of Road Geometric Design In Serbia, Xu Da, Yang Xueyong, Yuan Yingshuang, Chen Dongsheng

Journal of China & Foreign Highway

With the continuous advancement of China's Belt and Road Initiative，more and more Chinese enterprises are participating in the construction of engineering projects in Central and Eastern Europe，which brings some challenges for designers to master and use local codes for engineering design and consultation.According to the concrete practice of road reconstruction design of Hungary-Serbia Railway （Serbia section ），the application of horizontal and vertical indexes in road geometric design in Serbian was summarized.It is found that road design in Serbian has perfect design standards and systems.The Serbian code and the Chinese code are relatively close in terms of road geometric design standards，and …

Effect Evaluation Method Of Foamed Asphalt Based On Digital Image Processing Technology, Chang Xiaoyu

Journal of China & Foreign Highway

In view of the shortage of deter mining the optimal foaming parameters of foamed asphalt only by experience，this paper adopted digital image processing technology to collect images of the mixture of foamed asphalt and milled material RAI obtained under different foaming conditions and carried out grayscale image conversion，morphological processing，binary image conversion，and image segmentation，so as to calculate the asphalt wrapping rate in different areas.With the uniform dispersion of asphalt in the mixture as the indicator，the foaming effect of foamed asphalt was evaluated，and the optimal foaming parameters were determined.The results show that the digital image processing technology can quickly and effectively evaluate …

Research On Construction Risk Of Desert Highway Subgrade Engineering Based On Sem, Wang Shouxu, Han Lingyun

Journal of China & Foreign Highway

Highway construction in desert areas is of great significance to improving the nodes of transportation networks and developing the economy of remote areas.In order to effectively explore the construction risks of desert highway subgrade engineering，the five aspects of personnel risk，technical risk，material risk，mechanical risk，and environmental risk were analyzed，and 23 indicators affecting the construction risk of desert highway subgrade engineering were screened out by literature research method.Based on the effective data collected by questionnaire survey，a structural equation model （SEM ） of the construction risk of desert highway subgrade engineering was constructed，and the key influencing factors of the construction risk were analyzed.The results …

Rut Development Law And Correction Factor Of Axle Load Conversion Of Asphalt Pavement In Long And Large Longitudinal Slope, Guo Chenchen, Ding Tingting, Lyu Xin, Sun Jianxiu, Zhang Jizhe, Yao Zhanyong

Journal of China & Foreign Highway

The existing design specifications do not make special design provisions for pavements in long and large longitudinal slopes，and the directly applied design specifications ignore the stress characteristics of these pavements，which fail to guarantee pavement performance and life.In order to realize the differential design of the pavement structure of special road sections，based on the measured dynamic modulus of asphalt mixture，annual traffic volume，and temperature data，this paper used the self-developed temperature-axle load analysis software to convert the real traffic volume into standard axle load.Abaqus software was used to establish a rut model under the coupling effect of measured axle load and temperature，and the …

Mechanical Behavior Of Composite Structures Of Wearing Course And Underlying Layer For Asphalt Pavements, Yang Xiaohua, Yuan Zhanwen, Wen Yongbing, Zhou Chao, Wu Hao

Journal of China & Foreign Highway

The interlayer bonding state of pavement structures changes due to the influence of various factors under service conditions，and this change exhibits a significant influence on the mechanical behavior of pavement structures.Through the composite structure test and numerical analysis，the mechanical behavior of the composite structure of different wearing courses and underlying layers under different stresses and bonding states was studied.The test used three commonly used wearing course （surface layer ） materials of asphalt pavements，namely AC- 13，OGFC- 13，and SMA- 13 for comparative analysis.The test results show that different composite structures exhibit different interlayer bonding properties and fatigue characteristics due to the difference …

Shear Strength Test Of Hefei Expansive Soil Under Low Stress Conditions With Controlled Suction, Hou Chaoqun, Zhang Rongjian, Li Yongxin

Journal of China & Foreign Highway

Topsoil slide and instability of expansive soil slopes may occur under variable saturation conditions.In order to study the strength characteristics of unsaturated expansive soil under low stress conditions，several different matrix suction and stress conditions were set by unsaturated triaxial apparatus.The triaxial shear test of Hefei expansive soil was carried out，and the test data were analyzed.The test results show that when the net confining stress on the expansive soil continues to weaken，the stress-strain curve transitions from strain hardening to strain softening.The strength of unsaturated expansive soil increases with increasing matrix suction.The shear strength of shallow expansive soil shows a significant reduction …

Influence Of Aerodynamic Shape Change On Wind Resistance Performance Of Large Span Truss Bridge, Jing Dade, Su Yi

Journal of China & Foreign Highway

The development of the transportation an d tourism industry has led to bridges fulfilling additional roles，such as tourism，alongside their transportation functions，resulting in significant changes in structural aerodynamic shape and ventilation rate.This paper analyzed a double-tower single-span steel truss suspension bridge with a main span of 1 088 m，re-evaluated its wind resistance performance through the full-bridge aeroelastic model wind tunnel test，and evaluated the pedestrian comfort problem while studying the wind-resistant stability of the structure.The results indicate that the structural dynamic characteristics of the bridge remain almost unchanged before and after altering the aerodynamic shape of the bridge for its scenic spot …