Transportation Engineering Commons^™

Modeling And Generating Crash Avoidance Behaviors In Safety-Critical Vehicle–Pedestrian Interactions Using Deep Reinforcement Learning, Qingwen Pu

Civil & Environmental Engineering Theses & Dissertations

Traffic crashes between vehicles and pedestrians arise from complex, split-second interactions in which both parties make rapid evasive decisions. Four fundamental gaps persist in existing research. Surrogate safety measures assume linear trajectories, failing to capture the curved movements of turning vehicles and crossing pedestrians at intersections. Single-agent modeling treats one party as a fixed obstacle, ignoring the joint decision-making that governs near-miss outcomes. The effect of vehicle type on pedestrian avoidance behavior—whether pedestrians respond differently to automated vehicles (AVs) than to human-driven vehicles (HDVs)—remains poorly understood. Finally, automated driving system development is hampered by a severe scarcity of large-scale, behaviorally …

0905: American Car And Foundry (Acf) Collection, 1916-2019, Marshall University Special Collections

Guides to Manuscript Collections

The collection includes only documents that were found in the plant in 2021. These primarily consist of files on capital projects from the 1970s through the 1990s. Also included are notebooks with job descriptions and classifications; ledger books containing maintenance purchase orders; quality assurance manuals; visitors register books from 1973-2019; drawings of plant machinery and operations; slides and photographs; and miscellaneous materials.

The forerunner to ACF was Ensign Manufacturing Company, founded in 1871 at Huntington, West Virginia, by William H. Barnum and Ely Ensign, both from prominent families of Lime Rock, Connecticut. It was chartered (incorporated) on November 1, 1872, …

Impact Of Asphalt Binder Chemical Composition On The Performance Of Asphalt Mixture., Sagar Parajuli

LSU Master's Theses

Asphalt binder is composed of four chemical fractions, namely, saturates, aromatics, resins, and asphaltenes (SARA). Binders with the same performance grade (PG) can exhibit different chemical compositions due to variability in crude oil sources and refining processes. The objective of this study was to evaluate how such chemical variations influence the mechanical performance of asphalt mixtures at high, intermediate and low temperatures.

Eighteen 12.5-mm nominal Maximum Aggregate Size mixtures were designed using two aggregate types (limestone and gravel), and three binder grades (PG 67-22, PG 70-22m and PG 76-22m), each from three different sources with varying chemical fractions. A suite …

Feasibility Of Using Untreated And Treated Rice Straw Fibers As A Modifier For Hot Mix Asphalt, Aditya Chowdhury

Civil Engineering Theses

Flexible pavements are subject to progressive deterioration driven by repeated traffic loading, environmental exposure, and material degradation, which causes distress. This study presents an integrated research framework that combines laboratory performance evaluation of rice straw fiber (RSF)-modified hot mix asphalt with machine learning-based pavement distress prediction to advance sustainable pavements. Three plant-produced HMA mixtures were modified with untreated and alkali-treated RSF at dosage levels of 0.2%, 0.4%, and 0.6% by total mixture weight. FTIR spectroscopic analysis confirmed that alkali treatment induced significant chemical modifications to the fiber surface, increasing hydroxyl group availability and enhancing fiber–binder adhesion. Alkali-treated RSF consistently outperformed …

How Does Competitive Adsorption Between Vma And Pce Influence Yield Stress Of Cement Paste? A Novel Insight From Interparticle Forces And Percolation Threshold, Huamin Sun, Le Teng, Xiaohan Yu, Xin Shu, Zhangli Hu, Jiaping Liu, Kamal H. Khayat

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Viscosity modifying admixture (VMA) and polycarboxylate superplasticizer (PCE) are often combined to optimize rheological properties of cement-based materials. However, the competitive adsorption of these complex admixtures can greatly influence rheological properties. Many studies have investigated the variation of yield stress due to competitive adsorption between VMA and PCE; but the mechanisms are not fully understood. This study aims to shed a new light on this question in cement paste systems prepared with low water-to-binder ratios of 0.16–0.30. The competitive adsorption of VMA and PCE was quantitatively assessed using the Total Organic Carbon and Ultraviolet-Visible Spectroscopy measurements. The effect of competitive …

On The Use Of Lorawan For Smart Fishing Applications In The Blue Economy Sector, Eva Shayo

Tanzania Journal of Engineering and Technology (TJET)

The growth of digital technology is expected to transform small-scale fishery sectors, where a need for robust, low-cost, long-range communication networks becomes critical. There exist several technologies that are used in the fishery sector but they are never affordable to small scale fisheries. This study evaluates the feasibility of using low cost Long Range Wide Area Network (LoRaWAN) technology specifically tailored for smart fishing environments to small scale fishery sector. Using simulation, we assess the performance of the key performance metrics including probability of success and energy efficiency under varying device densities and time. During evaluation, we considered end devices …

Study On Deformation Characteristics Of Kaolin Under Dry-Wet And Freeze-Thaw Cycles, Yang Shang, Xiao Dingyuan

Journal of China & Foreign Highway

In seasonally frozen areas, surface soil is subjected to prolonged and drastic fluctuations in temperature and humidity, causing excessive deformation and resulting in engineering issues such as subgrade settlement and building deformation. The deformation characteristics of kaolin in seasonally frozen areas under the combined influence of freeze-thaw and dry-wet cycles were studied. Through a self-designed experimental setup, experiments with interleaved dry-wet and freeze-thaw cycles were conducted on compacted specimens, and wetting-freezing-thawing-drying cycle experiments were performed to explore the swelling-shrinkage deformation characteristics of kaolin under the combined action of different freeze-thaw and dry-wet cycles. The results indicate that intermittent freeze-thaw cycles …

Influence Of Geocell Technical Parameters On Bearing Characteristics Of Highway Subgrades In Oasis Areas, Zhu Chunsheng, Shu Xingyu, Lu Huiyu, Yang Xiaohua

Journal of China & Foreign Highway

To study the effects of technical parameters, such as geocell specifications and laying types, on the bearing capacity and deformation of highway subgrades in oasis flood irrigation areas, the shear properties of plain soil and geocell-reinforced layers with different specifications were studied through large-scale direct shear tests. Based on indoor compression tests and field load tests, numerical simulation parameters, such as the deformation modulus of different foundation soil layers, were calibrated. A numerical model of the geocell-reinforced highway subgrade was established using, and the effects of geocell specifications and laying types on the vertical settlement of the subgrade, the displacement …

Study On Effects Of Phase Change Materials On Thermal Erosion Resistance Of Airport Pavement, Li Ping, Li Yunlong, Zheng Zhipeng, Wang Zhijian, Yi Chengxi

Journal of China & Foreign Highway

To investigate the effect of phase change materials (PCMs ) on improving the thermal erosion resistance of airport pavements and to provide recommendations for selecting optimal PCMs to obtain airport pavements with longer service lives, three PCMs, PCM-G- 98 (A), LB- 2 (B), and TH-HC- 120 (C), were purchased based on literature summaries and market research. Based on microscopic test results and the actual preparation conditions of modified asphalt, PCMs A and B were selected. Subsequently, based on a self-made high-content SBS modified asphalt (S), four groups of composite modified asphalts (S-A- 5, S-A- 10, S-B- 5, and S-B- 10) …

Study On Influence Of Elastic Modulus Of Fiber On Compaction Characteristics Of Asphalt Mixtures, Zou Zexi, Luo Kaiyan, Lin Zhiming, Qiu Xiang, Lu Xudong, Yao Xiaoyang, Wang Yaolong

Journal of China & Foreign Highway

To investigate the influence mechanism of fiber incorporation on the compaction characteristics of asphalt mixtures, six types of typical road fibers (polyester fiber, polyacrylonitrile fiber, aramid fiber, basalt fiber, polypropylene fiber, and polyvinyl alcohol fiber) were selected in this paper, and gyratory compaction tests were conducted based on AC- 20 graded mixtures. The compaction coefficient (a larger compaction coefficient indicates easier compaction) was used as the core evaluation index. The results indicate that the elastic modulus of the fiber is the key influencing factor. When the fiber modulus is 50% lower than the aggregate modulus (such as polyester fiber and …

Angularity Evaluation Of Coarse Aggregates Based On Local Feature Extraction Of Point Clouds, Ma Quanzhuo, Feng Ponan, Feng Zezhong, Lei Mingyu, Wang Zhenfeng, Li Jiange

Journal of China & Foreign Highway

The morphological characteristics of coarse aggregates significantly affect the mechanical properties of asphalt mixtures and thus directly influence their road performance and durability. This paper aims to innovatively propose an evaluation method for the angularity of coarse aggregates. A three-dimensional (3D) scanner was used to acquire the surface profile information of coarse aggregates, and local angularity features were extracted through point cloud data analysis. Subsequently, a comprehensive 3D angularity evaluation index for coarse aggregates (A3D) was proposed by combining local normal vectors and curvature characteristics. The results indicate that A3D can be more accurately and independently used for angularity evaluation. …

Optimization Design And Experimental Study On Strength Of Ternary Industrial Solid Waste Mixtures, Yang Shu, Ai Yi, Sheng Shanwang, Li Chuangmin

Journal of China & Foreign Highway

This paper aims to explore whether fly ash, lithium slag, and slag powder (ternary industrial solid wastes) can effectively replace cement as cementitious materials for interlocking large-particle crushed stone bases. A uniform design table U9(94) was used to design the test scheme for the mixing ratios of ternary industrial solid waste mixtures; the correlation between the mortar strength and the ternary industrial solid waste mixtures was analyzed by Pearson correlation; with the help of the mathematical statistical software SPSS 26.0, mathematical models for the flexural strength and compressive strength of the ternary industrial solid waste mixture mortar specimens were established. …

Calculation Of Tensile Force For Cable-Stayed Buckling Bracket Combined With Temporary Tie Rod Structure Of V-Shaped Pier, Zhao Xiaolu, Yang Guang, Liu Junle, Qiu Zhiwei, Meng Lingxin, Peng Weibing

Journal of China & Foreign Highway

To solve the problem of excessive tensile stress of the cross-section during the cantilever casting process of high piers with inclined legs, a determination method of tensile force based on the linear programming theory and unstressed state control was proposed. Based on the internal force equilibrium method and the principle of influence matrix, the method optimized the tensile force with “stress control as the primary and alignment control as the auxiliary”. The unstressed state control method was adopted for forward iteration, and the effect of tangential displacement between segments was considered to verify the alignment of the inclined legs. Finally, …

Analysis Of Influence Of Cable Clamp Slippage On Internal Force And Alignment Of Main Cable, Zhu Kun, Liao Dinghui, Hu Chengze, Shen Heshun, Cao Hongyou

Journal of China & Foreign Highway

To investigate the influence of cable clamp slippage on alignment and internal force of the main cable, a theoretical analysis method based on node coordinates of the main cable after cable clamp slippage was proposed in this paper. Based on segmented catenary theory, the influence of hanger inclination caused by hanger slippage on the horizontal force of the main cable was considered. The segmental cable element of the main cable was equivalently expressed as expressions of hanger tension and unstressed length. With total unstressed length kept constant as a control condition, the horizontal force of the main cable was iteratively …

Study On Structural Design And Load Transfer Performance Of 6-Hole Flat Anchor Plate, Liao Yuanyuan, Ling Lihua, Wu Qibin, Cheng Bin, Dai Dongming

Journal of China & Foreign Highway

For negative bending moment prestressed tendons in simply supported-to-structurally-continuous bridges, the flat anchorage method of flange plate is more reasonable, but its widespread application is limited due to the anchoring capacity restrictions of flat anchor plates. To improve the anchoring capacity of a single anchorage zone, reduce the number of prestressed ducts, save concrete, and improve construction efficiency, a novel 6-hole flat anchor plate was developed, designed, and manufactured in this paper. By combining finite element analysis and experimental methods, a finite element analysis model of the concrete load transfer specimen beneath the novel 6-hole flat anchor plate was established, …

Analysis Of Shear Bearing Mechanism And Influencing Factors Of Mcl-Shaped Composite Dowel Connector, Zeng Zhuo, Zhou Baicheng, Cheng Xianjie, Cao Zhengxing, Gao Rongxiong, Wang Zichao

Journal of China & Foreign Highway

To investigate the bearing mechanism of modified clothoid (MCL)-shaped composite dowel shear connectors and the influence laws of various factors on their shear bearing capacity, the stress states and failure modes of the steel dowel, concrete dowel, and transverse through-reinforcement that constitute the MCL-shaped shear connector were deeply analyzed in this paper based on an experimentally validated finite element model. Furthermore, the influence laws of transverse through-reinforcement, steel dowel thickness, and concrete strength on the shear bearing capacity of the MCL-shaped composite dowel were explored. The research results indicate that the bearing process of the MCL-shaped composite dowel exhibits elastic, …

Research On Improving Bearing Capacity Of Full-Scale Prestressed Concrete Small Box Girders, Huang Jianyun, Gao Linli, Liu Zufeng, Ma Jinku, Ma Ming, Wang Xiaoguang

Journal of China & Foreign Highway

To solve the problems of lacking comparative research on the improvement effects of different reinforcement methods when formulating reinforcement schemes for prestressed concrete small box girders and that existing bearing capacity improvement tests mostly focus on scale models with insufficient reliability of results, full-scale model tests and numerical simulation analysis of five 30 m span prestressed concrete small box girders with different joint reinforcement measures were conducted in this paper. Finite element models for two single reinforcement measures were established, and the improvement effects of different reinforcement methods on the bearing capacity of prestressed concrete small box girders were studied. …

Key Construction Technologies For Single-Tower Rotating-Cable Suspension Bridges With Steel Truss Girders In Mountainous Regions, Gao Shuangjian, Zhang Weichao, Fu Lihong, Zhu Shuo

Journal of China & Foreign Highway

Given the problems of narrow construction sites, difficult construction organization, and high safety and quality risks faced in the construction of bridges in steep canyon regions of mountainous areas, this paper carried out research on key technologies for bridge construction in mountainous areas based on the Yellow River Three Gorges Bridge of the Jiyuan‒Xin’an Expressway. For the excavation of deep and large anchorage foundation pits in mountainous areas, a technical scheme of “loosening controlled blasting combined mainly with mechanical excavation and supplemented by manual excavation” was adopted. As this project is a single-tower single-span ground-anchored rotating-cable suspension bridge, the technologies …

Mix Proportion Design Of Tunnel Shotcrete Based On Diorite Manufactured Sand, Song Funing, Wang Zegang, Liu Naifei, Song Zhanping

Journal of China & Foreign Highway

Tunnel construction produces a large amount of waste slag, which cannot be effectively utilized due to various factors. By using tunnel slag to prepare manufactured sand to replace natural sand, resources can be saved; costs can be reduced, and the environment can be protected. Based on the Xi’an‒Shiyan high-speed railway project, the physical and mechanical properties of diorite along the tunnel were tested; the physical properties and concrete performance of manufactured sand and natural sand were comparatively studied, and the effects of water-binder ratio and sand ratio on the performance of shotcrete were analyzed by designing multiple sets of mix …

Surface Deep Well Dewatering Methods For Tertiary Water-Rich Semi-Diagenetic Section Of Wangjiazhai Tunnel, Liu Chengwen, Liu Gang, Xu Hua, Wei Meng

Journal of China & Foreign Highway

The tertiary semi-diagenetic sandstone of the Wangjiazhai Tunnel on the Yunnan Linqing Expressway is characterized by loose structure, low diagenetic strength, and poor cementation. The geological disasters such as collapse, water gushing, and mud bursting are very easy to happen when the tunnel passes through the water-rich section. With the surface deep well dewatering of the tertiary water-rich semi-diagenetic section of Wangjiazhai Tunnel as an example, the surface deep well dewatering methods and key parameters for tunnel crossing the tertiary water-rich semi-diagenetic section were discussed. Based on the single well surface dewatering test, the groundwater level and strata permeability of …