Materials Science and Engineering Commons^™

Curing Law And Road Performance Of Polyurethane Mixture, Sun Shengkai, Zheng Mao, Tang Xiong, Liu Li, Zhong Shengran, Si Te

Journal of China & Foreign Highway

Polyurethane mixture is composed of polyurethane binder，rubber particles，and stones.Compared with ordinary asphalt mixture，it has the characteristics of a higher content of rubber particles and large void ratios.This article first tested the viscosity-time curve and viscosity-temperature curve of one-component polyurethane and determined the compaction temperature of the polyurethane mixture.Based on the rutting test，three-point bending test，water immersion Marshall test，freeze-thaw splitting test，and pendulum friction test，the road performance of the polyurethane mixture under different replacement amounts of rubber particles was tested.The research results show that the mixing temperature of PU- 1 polyurethane mixture can be basically controlled between 73 ℃ and 81 ℃，and it …

Elimination Method Of Temperature Lag Effect In Deformation Monitoring Data Of Cable‑Stayed Bridge Structures, Liu Hongshuang, Zhai Wenqiang, Zeng Guoliang

Journal of China & Foreign Highway

There is a temperature lag effect in the deformation monitoring data of the bridge structure.Eliminating the temperature lag effect is of great significance in the health monitoring of the bridge structure.Based on the linear correlation between the deformation of the bridge structure and the temperature，this paper applied the goodness of fit test and proposed a time-domain translation elimination method.On this basis，by taking the long-term synchronous monitoring of the tower inclination，beam end displacement，main girder deflection，and temperature data of a cable-stayed bridge as an example，this method was used to eliminate the temperature lag effect in the deformation monitoring data and compared with …

Dynamic Response Analysis Of Bridge Under Combined Action Of Random Traffic Flow And Wind Based On Simpack Platform, Xiong Tao, Han Yan, Ma Xingchuan, Li Qianming, Yan Naijie, Zhang Fei, Hu Peng

Journal of China & Foreign Highway

To deal with the time-consuming problem of calculating the dynamic responses of the bridge under the combined action of random traffic flow and wind，a steel box continuous girder bridge was taken as the engineering background，and the finite element model of the bridge and the vehicle model were established in the commercial software Ansys and SIMPACK，respectively.Then，the dynamic responses of the bridge subjected to the single vehicle load，wind loads，and multiple vehicle loads were calculated to verify the superposability of the dynamic responses of the bridge.On this basis，the Monte Carlo method was used to generate the random traffic flow samples.By using the verified …

Sensitivity Analysis Of Parameters Of Cable‑Stayed Bridges With Full Floating Spatial Frame, Liu Anqing, Yan Tengfei, Zheng Pengju, Gu Yanlin, Li Jie, Wang Qiang

Journal of China & Foreign Highway

In order to clarify the influence of design parameters on the mechanical behavior of a cable-stayed bridge of a floating system，a finite element model of the bridge was established by using the finite element analysis software MIDAS/Civil based on a single-tower double-cable plane steel-concrete composite beam cable-stayed bridge with full floating spatial frame.The sensitivity of parameters such as temperature effect，secondary dead load，and support system in the completed bridge state was analyzed and compared with the semi-floating system of the bridge.The results show that temperature and secondary dead load have a significant impact on the deflection and stress of the main …

Experimental Study On Shear Behavior Between Nrc‑Uhpc Interface, Chen Zhenkan, Li Junsheng, Shi Quan, Fang Haozhen, Mo Fan, Jiang Haibo

Journal of China & Foreign Highway

In order to investigate the effect of the screw diameter of planted bars and ultra-high performance concrete （UHPC） pouring method on the shear behavior of normal reinforced concrete （NRC） and UHPC， two groups of six push-out specimens were designed for shear behavior tests.The results show that after the failure of the concrete bonding force in the NRC-UHPC interface，the screw can maintain shear behavior so that the failure process of the specimen after the load reaches the peak shows ductile characteristics.For specimens with screw diameters of 12 mm and 16 mm，greater screw diameter indicates higher shear capacity of the specimens and …

Design And Construction Process Of Cross‑Beam Supports For Main Tower Of Changtai Changjiang River Bridge, Zeng Jian, Hu Pei, Wang Chao

Journal of China & Foreign Highway

The construction of the lower cross-beam structure of the main tower of Changtai Changjiang River Bridge has the characteristics of high construction height，large amount of concrete earth volume，and difficult control of down-warping deformation.In order to implement the pouring of the lower cross-beam of the main tower，floor-type steel pipe supports were set at the lower cross-beam，which were used to support the lower cross-beam formwork and bear the load during the concrete pouring.Through the finite element software analysis and calculation，it was found that the asymmetric deformation of the main structure of the lower cross-beam could be effectively controlled，and the overall force of …

Segment Connection Mod E For Stiffening Girder Hoisting Construction Of Long‑Span Steel Truss Girder Suspension Bridge, Shao Guangmiao, Pan Q Uan, Yan Donghuang, Xu Hongsheng

Journal of China & Foreign Highway

In the process of stiffening girder construct ion of a long-span steel truss girder suspension bridge，different connection modes of stiffening girder segments will directly affect the internal force，alignment，and bridge state of the structure during construction.By taking the construction of the stiffening girder of a bridge as the research background，the finite element model of the whole process of the bridge was established.The advantages and disadvantages of the segmented hinge method and the segmented rigid connection method were compared，and the two-two segmented rigid connection scheme was proposed.On this basis，according to the changing law of steel truss section alignment and lower chord opening …

Research On T‑Beam System With Diaphragm Based On Intelligent Construction, Liu Lang, Tao Qiyu, Xu Qigang

Journal of China & Foreign Highway

The traditional precast T-beam faces issues such as excessive diaphragms，difficult formwork installation and removal，and low levels of intelligence in intelligent bridge construction.To address these issues，this paper focused on the optimization of the number of diaphragms and the application of prefabricated diaphragms.By analyzing different diaphragm configuration schemes and comparing the contributions of prefabricated diaphragms and precast diaphragms to the lateral stiffness of the bridge，this paper deeply explored the impact of diaphragms on bridge performance.The research results indicate that the T-beam system with fewer diaphragms is feasible in intelligent construction，but the system without diaphragms places higher demands on the performance of bridge …

Determination Of Manufacturing Parameters Of Large Section Of Continuous Steel Box Beam With Variable Section In Shenzhen‑Zhongshan Passage, Dong Chuangwen, Chen Long, Li Chuanxi

Journal of China & Foreign Highway

Accurate calculation of manufacturing parameters is the key to the efficient，high-precision，and rapid installation of large sections of continuous steel box beam bridges.Taking the steel box beam with the variable section in Shenzhen-Zhongshan Passage as the background，this paper first established a finite element model of the beam element in the whole construction process to obtain the pre-camper.Secondly，the average neutral axis position was calculated based on the height of the neutral axis of each beam section.Then，according to the deformation characteristic that the beam length remained unchanged at the mean neutral axis，the pre-camber was superimposed at the mean neutral axis to get the …

Key Technology For Construction Of New Single‑Wall Steel Suspended Box Cofferdam With High Pile Tied Beams In Deep Water, Yang Jinlong, Zhao Lin, Jiang Qunlong

Journal of China & Foreign Highway

In order to ensure the safe，efficient，and economical completion of the construction of the high pile tied beam of Muping Xiangjiang River Bridge in deep water，a new type of single-wall steel suspended box cofferdam was designed to act as the water retaining and enclosure structure during high pile tied beam construction according to the characteristics of deep water level and shallow stratum cover layer at the high pile tied beam location.Through the innovative design of steel casing on the bottom of the steel suspended box cofferdam，the design height of the wall panel and the amount of steel input were reduced.On the …

3d Reconstruction Method Of Tunnel Surrounding Rock Fracture Based On Vtk, Liu Houxiang, Su Heng

Journal of China & Foreign Highway

Fracture parameters are important reference factors for surrounding rock stability analysis.To realize the visualization analysis of surrounding rock fractures，this paper proposed a three-dimensional （3D） reconstruction method of surrounding rock fractures based on the visualization toolkit （VTK）.Firstly，the collected tunnel surrounding rock images were preprocessed by OpenCV for image grayscale and noise reduction.Secondly，the Otsu method and the open operation in morphology were used to segment the image，and the complete surrounding rock fracture map was obtained.Then，the median method was used to replace the linear interpolation method with the traditional Marching Cubes algorithm in VTK to calculate the equivalent point，and the improved Marching Cubes …

Surface Grouting Reinforcement Technology For Shallowly Buried Tunnel In Coastal Zone, Xiang Ze, Deng Shiping, Sheng Zhang, Zhou Ye, Wang Wei, Pei Yabing

Journal of China & Foreign Highway

The Ⅵ level surrounding rock section of a project water intake tunnel is located in the coastal zone，with thick overlying sand layers，broken surrounding rock，and other characteristics.To address these issues，laboratory tests were conducted to explore the effect of water glass volume dosing on the final setting time and strength of cement-sodium silicate （CS） liquid slurry，and field tests were carried out for a comprehensive analysis of grouting methods.The constraint-dispersion mode was finally determined to divide the grouting area into several small grouting units.Advance plastic pipe grouting reinforcement was performed according to the grouting sequence of the outermost circle hole interval first，followed by …

Key Technology For Incremental Launching Construction Of Double Guide Beam Of Steel Box Girder, Sun Xiaoqiang, Yue Xinxing

Journal of China & Foreign Highway

By taking the incremental launching construction of the steel box girder at the 6th hole of the approach bridge of Baoji Taigu Bridge as the engineering background，the original plan adopted single-guide beam multi-point walking incremental launching technology for assembly and incremental launching on the prestressed reinforced concrete beam of the adjacent hole.Since the middle span of the concrete beam cannot withstand the concentrated force at the incremental launching points，the multi-guide beam multi-point walking incremental launching technology was finally used to arrange the incremental launching points at the transverse diaphragm plate of the end of the concrete beam.By increasing the incremental …

Influence Factors Of Carbonization Of Tunnel Segment Structure And Life Prediction Analysis, Li Dongbiao, Miao Miao, Shen Caihua, Chen Wei

Journal of China & Foreign Highway

There are many factors that affect the carbonization life of concrete segments in underwater tunnels，and the prediction methods are not uniform.In this paper，combined with actual engineering，the influencing factors and laws of carbonization of concrete segments in underwater tunnels were analyzed，and three methods for predicting the life of concrete segments were established with the crack limit as the control target.The prediction results of the three methods were compared.The results show that the influence of the temperature and CO2 concentration in the tunnel predicted by the three methods on the life of the tunnel lining structure is basically consistent with the existing …

Emergency Vehicle Dispatching Model Considering Demand Urgency And Delivery Fairness, Long Kejun, Liu Jia, Gao Zhibo, Chen Suqian, Zhang Zhonggen

Journal of China & Foreign Highway

In emergency vehicle dispatching after unexpected events，it is crucial to prioritize critical nodes with high demand urgency while minimizing excessive delivery delays at other nodes to prevent secondary impacts.On this basis，this study developed an emergency vehicle dispatching model that considered demand urgency and delivery delay fairness.Firstly，the entropy weight-TOPSIS method was used to calculate the demand urgency for each node，and a delivery delay balance index was introduced to minimize disparities in delivery delays between nodes.Secondly，a multi-objective optimization model was established with total delivery time，overall cost，and delivery delay balance as objectives，while considering constraints such as inventory levels at distribution centers and route …

Research And Practice On Demolition Of Lane Separator In Same Direction Along Zhengzhou‒Luoyang Section Of Lianyungang‒Khorgos Expressway, Zhang Nan, Ji Xiang, Ma Gang

Journal of China & Foreign Highway

In order to solve the problem arising after the demolition and closure of the lane separator in the same direction along the expressway，this paper systematically introduced the reconstruction method of the lane separator in the same direction by studying the overhaul project along Zhengzhou-Luoyang section of Lianyungang‒Khorgos Expressway.The paper explored the main diseases and potential safety hazards existing in the lane separator in the same direction by checking the compliance of specifications，analyzing the traffic operation status，exploring the characteristics of traffic accidents，and investigating the traffic safety facilities.On this basis，it demonstrated the feasibility of demolishing the lane separator in the same direction.According …

Linkage Control Method For Expressway Toll Stations And Plane Intersections, Lei Qing, Wang Zhaoyong, Wu Yurong, Jiang Weiwei, Luo Zhongbin

Journal of China & Foreign Highway

In order to solve the problem of vehicle queuing overflow caused by the mismatch between the expressway toll stations and the capacity of plane intersections，the formula for calculating the maximum queue length was given by analyzing the traffic operation characteristics between toll stations and plane intersections and considering vehicles ’ lane-changing behavior.Due to the strong coupling of the traffic operation between toll stations and plane intersections caused by a short distance between them，a unified linkage control optimization model was established.The research shows that if the queue length in the connecting direction of the plane intersections exceeds the allowable maximum queue …

Working Properties Of Steel Tube Batter Piles With Concrete Infill Based On Abaqus, Yang Meiliang, Li Liemin, Sun Kunjiang, Han Rui, Zhong Yang

Journal of China & Foreign Highway

In order to explore the respons e characteristics of steel tube batter piles with concrete infill under vertical load，the steel tube batter pile with concrete infill used in Saribas Bridge in Malaysia was taken as the research object.Based on the numerical simulation method，the frictional resistance of the inner and outer walls of the steel tube，the frictional resistance around the pile at the section，and the bending moment bearing ratio between the steel tube and the concrete core of this type of batter pile under vertical load were studied.The results show that the passive-side frictional resistance of the 0–15 m pile section …

Ge/Sige Quantum Wells: Material For The Post-Moore Era, Troy Alexander Hutchins-Delgado

Optical Science and Engineering ETDs

This dissertation demonstrates high-quality germanium quantum wells on a 200 mm silicon wafer platform, enabling novel device possibilities. Partnering with a commercial silicon-germanium epitaxy supplier, we obtained shallow, undoped germanium quantum wells with high-crystalline quality, confirmed through x-ray diffraction, secondary ion mass spectroscopy, high-resolution scanning transmission electron microscopy, and energy dispersive x-ray spectroscopy. Hall bar devices fabricated on single quantum wells revealed that surface preparation can tune transport properties while maintaining peak mobilities around 10⁵ cm²V⁻¹s⁻¹. Manganese-germanide spintronic contacts were integrated via solid-state reaction, with contact quality assessed through Schottky diodes, transfer length …

Magnetic Nano And Micro Rods As Tools For Characterizing Materials Mechanical Properties: Fundamentals And Applications, Artis Brasovs

All Dissertations

The focus of this dissertation is insect blood (Hemolymph). Hemolymph is analyzed by taking a materials science approach. Rheological characterization of hemolymph has been performed for the first time. Owing to a minute amount of available material, a new protocol was established where Magnetic Rotational Spectroscopy (MRS) with ferromagnetic nanorods was employed. The challenge was examining the microliter droplets' viscosity in less than a few minutes. This challenge was successfully resolved.

Blood is critical for the insect's survival: after wounding, the insect has to seal the wound quickly, in a few minutes. As the mechanism of fast clotting has never …

Influence Of Glycopolymer Structure On Amphiphilic, Hybrid, Linear Branched Block Copolymer Properties For Use In Biomedical Applications, Kevin Green

Dissertations

The focus of this dissertation is evaluating and adding fundamental knowledge regarding the structure-property relations of glycopolymers used in the design of hybrid block copolymers (HBC) that are cable of self-assembling into delivery vehicles for biomedical applications. A shift to the utilization of natural materials in the design and fabrication of drug-delivery vehicles has garnered significant attention. Understanding the effects of linear glycopolymers content and composition on the resulting HBCs properties can provide valuable insight into how these materials may be tailored for use in targeted biological applications.

The first chapter introduces current literature on the need for improvement in …

Development Of Uranium Fluoride Microstructures, Harry Jang

UNLV Theses, Dissertations, Professional Papers, and Capstones

Uranium microstructured materials with controlled size and shape have found applications in several branches of the nuclear industry including as targets for medical isotopes production, fuels for nuclear reactors, standards for analytical measurements, and energy sources for space exploration. Morphological studies of actinide materials are also highly relevant to nuclear forensics-related work. Other potential applications include information storage, catalysis, sensors, and luminescent devices. Most studies on uranium microstructured materials have focused on binary oxides, nitrides, carbides, and fluorides, with the spherical shape being the dominant morphology. Prior to the work reported in this dissertation, aside from UF4 microspheres (ms) and …

Thermal Conductivity Characterization Of High Oleic Vegetable Oils Based Hybrid Nanofluids Formulated Using Gnp, Tio2, Mos2, Al2o3 Nanoparticles For Mql Machining, Anthony Chukwujekwu Okafor, Tobechukwu Kingsley Abor, Saidanvar Esanjonovich Valiev, Ignatius Echezona Ekengwu, Abiodun Saka, Monday Uchenna Okoronkwo

Mechanical and Aerospace Engineering Faculty Research & Creative Works

This paper presents the results of thermal conductivity characterization of six high oleic soybean oil (HOSO) and four high oleic canola oil (HOCO)-based hybrid nanofluids formulated with four types of nanoparticles (Graphene nanoplatelet (xGnP), TiO2, MoS2, and Al2O3) at nanoparticles wt.% concentration from 1 % to 7 % in 1 % increment using the two-step method for use in MQL machining of difficult-to-cut metals. Thermal conductivity of the formulated hybrid nanofluids were measured using Thermtest Transient Hot Wire Liquid Thermal Conductivity Meter at temperatures from 25 °C to 75 °C in increment of 10 °C. Obtained results showed that thermal …

Striking A Balance: Market Shock & Responses In Automotive Components Manufacturing, Emma Lane Mcgahey

All Theses

This thesis examines the effects of extreme market shocks on supply chain dynamics within the automotive industry. Through an analysis of demand data from an automotive manufacturer to its component suppliers (January 2018 to May 2024), the study investigates the relationship between market shocks and supply chain responses, providing insights into how auto components inventory management handles downstream responses to market shocks. With supporting public data—from FRED, BLS, and the U.S. Census Bureau resources—we explore two primary relationships: the impact of market shocks on the Average Standard Deviation of Demand (SDO) and the effect of demand variability on expedited pricing …

Experimental Evaluation Of A Recrosslinkable Co2-Resistant Micro-Sized Preformed Particle Gel For Co2 Sweep Efficiency Improvement In Reservoirs With Super-K Channels, Adel Alotibi, Tao Song, Ali Al Brahim, Baojun Bai, Thomas P. Schuman

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

A recross linkable CO₂-resistant branched preformed particle gel (CO₂-BRPPG) was developed for controlling CO₂ injection conformance, particularly in reservoirs with super-permeable channels. Previous work focused on a millimeter-sized CO₂-BRPPG in open fractures, but its performance in high-permeability channels with pore throat networks remained unexplored. This study used a sand pack model to evaluate a micro-sized CO₂-BRPPG under varying conditions of salinity, gel concentration, and pH. at ambient conditions, the equilibrium swelling ratio (ESR) of the gel reached 76 times its original size. This ratio decreased with increasing salinity but remained stable …

Density-Driven Investigations Of Ruthenium Binary Compounds Rux2 (X = O, S, N), Melanie White

UNLV Theses, Dissertations, Professional Papers, and Capstones

Exploration and fine-tuning of the energy landscape of materials can be accessed by means of changes in material density, a key principle of high pressure research. Density-driven changes impact variations in oxidation states and coordination numbers for the element constituents of a compound. Pressure-induced modification of intrinsic density can promote the formation of new materials, variations in physical properties, and transformations in crystallographic symmetry. With this as our foundation, we focus on ruthenium binary compounds - altering the anion species to change electronegativity while probing pressure and temperature effects. This led us to the present study of ruthenium oxide RuO2, …

Removal Capabilities Of Zeolite And Zero Valent Iron With High-Level Waste Tank Radionuclides And Metals: Cesium, Strontium And Chromium, Colette R. Towles

UNLV Theses, Dissertations, Professional Papers, and Capstones

High level nuclear waste (HLW) has been disposed for temporary storage in underground steel tanks at the Department of Energy Nuclear sites. For example, at the Hanford Site, WA, and Savannah River Site (SRS), SC, HLW account for eighty-eight million gallons (Mgal) and 450 million Curies (MCi) of radioactivity. In the early nuclear activity at Hanford, the waste was discharged to single-shell steel tanks, and the lack of secondary containment allowed leaks, contaminating soil and groundwater. Despite tremendous efforts to stabilize the liquid waste at nuclear sites, treatment is complex, costly, and time-consuming; therefore, HLW may have to be stored …

Advancing Biofabrication Methodologies To Develop Biomimetic Tissue Scaffolds For Musculoskeletal Applications, Nashaita Yezdi Patrawalla

Theses and Dissertations

Musculoskeletal injuries impose a significant global burden, affecting millions and generating an economic toll exceeding $14 billion. Tissue engineering has gained traction as a promising strategy offering potential for functional restoration of damaged musculoskeletal tissues. This research aims to advance biofabrication techniques for generation of biomimetic tissue scaffolds, by optimizing scaffold design and modulating fabrication process parameters to generate scaffolds for musculoskeletal regeneration with application-specific tailored properties. In this realm, collagen-based biomaterials have been extensively investigated for tendon and ligamentous applications, and in combination with bioceramics incorporated into the collagen framework to produce composite scaffolds that better recapitulate the native …

Understanding Defect Dynamics In Black Phosphorene Under Noble Gas Ion Irradiation., Saransh Gupta

Electronic Theses and Dissertations

Controlled introduction of defects in phosphorene using high-energy ion beams offers a promising route to design novel high-performance materials for energy technologies. However, this potential remains underexplored due to a lack of fundamental understanding of the atomic-scale mechanisms governing the production, accumulation, and temporal evolution of defects during ion irradiation. Here, we employ a combination of classical and ab initio molecular dynamics simulations to elucidate the effects of ion energy, angle of incidence, noble gas ion size/mass, and fluence on (a) defect generation (i.e., point defects, topological imperfections, voids), (b) atomic-scale mechanisms of defect formation and re-arrangement, and (c) defect …

Thermal Conductivity Characterization Of High Oleic Vegetable Oils Based Hybrid Nanofluids Formulated Using Gnp, Tio2, Mos2, Al2o3 Nanoparticles For Mql Machining, Anthony Chukwujekwu Okafor, Tobechukwu Kingsley Abor, Saidanvar Esanjonovich Valiev, Ignatius Echezona Ekengwu, Abiodun Saka, Monday Uchenna Okoronkwo

Chemical and Biochemical Engineering Faculty Research & Creative Works

This paper presents the results of thermal conductivity characterization of six high oleic soybean oil (HOSO) and four high oleic canola oil (HOCO)-Based hybrid nanofluids formulated with four types of nanoparticles (Graphene nanoplatelet (xGnP), TiO₂, MoS₂, and Al₂O₃) at nanoparticles wt.% concentration from 1 % to 7 % in 1 % increment using the two-step method for use in MQL machining of difficult-to-cut metals. Thermal conductivity of the formulated hybrid nanofluids were measured using Thermtest Transient Hot Wire Liquid Thermal Conductivity Meter at temperatures from 25 °C to 75 °C in increment …