Materials Science and Engineering Commons^™

Application Of Forward-Ba Ck Ana Lysis And Difference Iteration Method For Solving Initial Cable Tension Of Arch Bridge, Xu Yufeng, Li Zihui, Zhang Zhantao

Journal of China & Foreign Highway

This article presented a method that c ombined the forward-back analysis method and the difference iteration method to solve the initial cable tension according to the state of a built bridge for an arch bridge.Given the known target state of the bridge,a reasonable set of initial cable tensions was determined as the initial value of iteration by the forward-back method.These initial tensions were then applied to the calculation model based on the actual construction process.Through the difference iteration method,the initial cable tensions were optimized.The results show that the method can effectively determine the final cable tension that meets engineering precision …

Experimental Study On Bending And Shear Performance Of Joint With Looped Reinforcement In Prefabricated Components, Liu Zhiquan, Hu Ke, Shi Xuefei, Zhong Yuzhuo

Journal of China & Foreign Highway

A joint with looped reinforcement is a type of steel bar connection structure with wet joints characterized by quick construction.In order to study the bending and shear stress performance and load-bearing capacity characteristics of the wet joints,four bearing capacity tests for bending and shear were designed and conducted for common application scenarios.The load,strain,and displacement changes of the specimens during the test process were tested,and the failure characteristics,load–displacement changes,and ultimate bearing capacity of this type of wet joint were analyzed.The results show that the wet joint with looped reinforcement has good ductility and conforms to the design principles of reinforced concrete.The …

Bending Moment Calculation And Reinforcement Recommendations For Cast-In-Place Cover Slabs In Slab Culverts, Li Yukun, Wan Kecheng, Fu Fulin

Journal of China & Foreign Highway

To address the complexity and lack of practical methods for calculating bending moments of cast-in-place cover slabs in slab culverts,the slabs were simplified as one-way slabs with a pair of opposing edges simply supported and the other pair of edges free.Theoretical formulas for calculating the bending moments within the slabs under uniformly distributed loads were derived using elastic theory.The accuracy of the theoretical formulas was validated through case studies via finite element software.Various combinations of length,width,and fill heights exist in highway projects,making the use of theoretical formulas for bending moment calculations cumbersome.Therefore,a simplified method for calculating maximum bending moments in …

Research On Whole-Hole Testing Technology For Under-Anchor Tension In Prestressed Concrete Girders, Zhu Jianzhao, Dong Hao, Gu Jungang, Feng Lu, Li Shuyang, Zhang Shoulong, Chen Chaung

Journal of China & Foreign Highway

This study aims to propose a new testing method,namely whole-hole back-pull testing technology,to reduce costs and increase efficiency in under-anchor tension testing,effectively addressing the engineering challenges of large testing volume and tight schedules.Based on the principle of the traditional back-pull method,the mechanism of whole-hole back-pull testing technology was explained through theoretical analysis and formula derivation.Technical optimization was carried out in conjunction with experimental research,and a complete application method was proposed.A feasibility analysis was carried out.The study obtained the simplified mechanical model and typical test curves of the whole-hole back-pull testing technology and proposed a formula and application method for determining …

Settlement Mechanism And Re Inforcement Measure For Large-Diameter And Small-Clearance Parallel P Ipe Jacking Undercrossing Complex Building, Tang Gang, Huang Wen Jie, Zhang Wenbo, Li Wenjie, Liang Bin

Journal of China & Foreign Highway

This study aims to study the settlem ent changes and distribution of various parts of a complex building during the construction of a large-diameter and small-clearance parallel pipe jacking undercrossing complex building.On the basis of the pipe jacking project of water quality guarantee engineering 2# for Tiegang –Shiyan Reservoir in Shenzhen,the settlement mechanism of pipe jacking undercrossing construction was analyzed.Through numerical simulation,the influence of the presence or absence of grouting reinforcement,and parameters such as longitudinal spacing and burial depth of pipe jacking on the variation trend and distribution law of building settlement was analyzed.The theoretically predicted values,numerical simulation values,and on-site …

Bridge Damage Detection And Bim Localization Methods Based On Image Recognition, Li Yu, Guo Hongjun

Journal of China & Foreign Highway

To overcome insufficient information of 2D detection data in traditional bridge maintenance,which hinders precise decision-making,this study proposed an automated method based on deep learning and structure from motion (SfM ) technology,which realized the complete process from image recognition to the accurate mapping of damage information in a building information model (BIM ).First,the YOLOv 8 deep learning model was used to automatically detect bridge surface damage.Second,the SfM technology was applied for the local 3D reconstruction of the damage area and to determine the 3D coordinates of the damage.Then,the least squares method was used to align the local coordinate system with the …

Bending Capacity And Strengthening Design With Bonding Steel Plates Of Concrete Sections In French Standards, Wu Zi

Journal of China & Foreign Highway

In the French general technical clauses widely used in Francophone African countries,only the calculation principles for the bending capacity of normal concrete sections are provided,with explicit formulas not listed,and the strengthening design of structures is not involved.According to the fundamental principles of concrete structures and French standard regulations,the calculation formulas for the bending capacity of normal concrete sections were derived.On the basis of the assumptions of strengthening design,calculation formulas for strengthening with bonding steel plates were derived.Through practical engineering calculations conducted on the VDN Expressway project in Senegal,the applicability and reliability of the proposed formulas were verified.This study can offer …

Quantitative Evaluation Of Tunnel Rock Mass Integrity Based On Mwd Technology, Zhang Kunmu, Peng Hao, Liang Ming, Han Yu, Song Guanxian

Journal of China & Foreign Highway

In tunnel construction,the quantitative evaluation of rock mass integrity heavily relies on information from the exposed face,and there are challenges when drilling data is used for integrity evaluation.To this end,this study introduced a novel method for quantitative evaluation of rock mass integrity during drilling,integrating numerical statistics with machine learning.A substantial dataset of digital drilling data was collected,covering three common types of rock mass integrity:relatively intact,relatively fractured,and fractured.Subsequently,a high-performance random forest model for the classification of rock mass integrity was developed through data preprocessing and hyperparameter optimization.The interpretability of the model ’s predictive results was enhanced using Shapley additive explanations (SHAP …

Object Detection And Tracking Based On Fusion Of Radar And Camera On Highway Side, Zeng Yongqiang, Zhang Yonghua, Zhao Hui, Liu Xin, Xu Mingsheng, Shen Jianwei, Hu Zhiwei, Chen Zhenquan

Journal of China & Foreign Highway

Camera is the most widely used sensor in intelligent transportation systems (ITS),but the decline of detection and positioning accuracy caused by target occlusion and external environment interference has always been an important factor restricting the development of ITS.In order to solve this problem,a multi-mode fusion target detection and tracking method based on millimeter-wave radar (MWR ) and camera on highway side was designed.Compared with cameras,high-resolution MWR had better measurement accuracy and weather robustness,serving as a better complement to camera perception.The proposed method used the center point-based radar and camera fusion algorithm for target detection and adopted the greedy algorithm for …

Use Of Alaçatı Stone Aggregate In Conventional And Self-Consolidating Concretes, Tahir Kemal Erdem

Journal of Sustainable Construction Materials and Technologies

Alaçatı stone or Alapietra stone is widely used mostly for building cladding. However, its production and use in the construction sites generate high amounts of waste (debris), causing environmental pollution in Çeşme which is a touristic district. This study investigated the reuse of Alaçatı stone as lightweight aggregate (LWA) in both conventional and self-consolidating concrete (SCC) mixtures. The concretes were prepared to have three different water-to-cement ratios (w/c), which were 0.38, 0.42 and 0.48. For each w/c, a conventional concrete mixture and two SCC mixtures with 60 or 70 cm slump flow were produced by varying the superplasticizer SP content. …

A Decision Support Model For Building Material And Component Reuse In The Context Of Circular Buildings, Havva Aksel

Journal of Sustainable Construction Materials and Technologies

Construction activities cause significant environmental impacts such as waste generation, pollution, resource consumption, and land use, which are expected to increase with global construction demands. To mitigate these environmental problems, the circular building occurs as an emerging concept depending on in the circular economy, which aims to minimize waste and redefine the “end-of-life” concept by reducing, reusing, recycling, and recovering materials. The reuse of building materials and components (BMCs) from existing structures represents a crucial strategy for achieving circularity in the built environment. Within this framework, design plays a key role. However, designing with reclaimed BMCs remains complex due to …

Design And Development Of Biomimetic Hydrogel Interfaces For Enhanced Bioelectrical Signal Acquisition, Daniela Nikoloska

UNLV Theses, Dissertations, Professional Papers, and Capstones

Every second, human skin processes over one million sensory signals while maintaining properties such as electrical conductivity, mechanical adaptability, and regenerative capability that surpass all synthetic materials. Contemporary bioelectronic devices prove inadequate when contacting skin surfaces due to poor adhesion and electrical contact issues that prevent effective sensing. Despite advancements in wearable and bioelectronic technologies, current devices face major drawbacks when interfacing with human skin, particularly in maintaining firm adhesion, conformability, and low-noise electrical signal acquisition.

This research focuses on the development of a biomimetic hydrogel-based interface for bioelectronic sensing. Specifically, a hybrid hydrogel system composed of polydopamine (PDA)- doped …

Analysis Of Leakage In Nearshore Pipelines Using Fitness For Service Method To Ensure Mechanical Integrity Based On Api-579 Level 3, Elriandri Elriandri, Dedi Priadi

Journal of Materials Exploration and Findings

The Fitness for Service (FFS) analysis is performed as a quantitative assessment to evaluate the integrity condition of a pipeline. Essentially, FFS assessment helps determine whether equipment components can operate safely despite existing deficiencies. This evaluation is carried out using the Finite Element Method (FEM). In the case of an underwater pipeline that experiences leak due to anchor pull at the flange connection, it undergoes plastic deformation and is lifted approximately 1 meter. As a mitigation step, inspection and repairs have been carried out by the company. Subsequently, modeling is performed to reconstruct the deformation process of the pipeline. Then, …

Assessment Of The Melt Quality Of A 30% Scrap Adc12 Aluminium Alloy Using The Inclusion And Fluidity Measurement Instrument (Ifmi) With Mullite Ceramic Filters, Gusti Ruri Ruri Lestari, Sandya Ananda Riswan, Muhammad Anis, Ahmad Ashari, Paramita Vidya Ayuningtyas, Bambang Suharno Prof, Donanta Dhaneswara

Journal of Materials Exploration and Findings

The increasing demand for sustainable practices in the metal casting industry has driven the use of recycled aluminum alloys such as ADC12. However, the addition of aluminum scrap tends to increase oxide inclusions, which reduce melt fluidity and compromise casting quality. This study utilizes the Inclusion and Fluidity Measurement Instrument (IFMI), equipped with mullite ceramic filters, to assess the melt quality of ADC12 aluminum alloy containing 30% scrap. Fluidity and inclusion characteristics were evaluated at five pouring temperatures (660°C, 680°C, 700°C, 720°C, and 740°C). The results show that fluidity increased with temperature, reaching a peak of 84.6 g·s⁻¹ at 740°C, …

Equipment Criticality Analysis To Determine Asset Integrity Management System Scheme In Supporting Production Optimization Scenarios In The Aeging Field, Donny Andryanto, Donanta Dhaneswara

Journal of Materials Exploration and Findings

This research investigates the production decline and cost increase in the X&Y oil and gas fields from 2022 to 2023. Production fell by 34%, while production costs per barrel rose by 79%. To address these issues, a series of optimization processes are proposed. These aim to restructure and enhance the production facilities to reduce current production costs. The optimizations include reducing pressure at the PPP Platform in 2024. Additional steps include shutting down CPP-ORF 14” pipelines and most processes at CPP 2 Platform by 2027 to convert it into an accommodation platform. Further, the plan involves optimizing the release of …

An Overview Of Biomass-Derived Graphene Oxide And Its Characteristics For Future Sustainable Applications, Afif Wardana, Ahmad Nabil Shahab, Donanta Dhaneswara, Nofrijon Sofyan

Journal of Materials Exploration and Findings

The production of graphene oxide (GO) from biomass presents considerable promise as a sustainable alternative substitute for traditional semiconductors. Biomass waste, abundant and often underutilized worldwide, is distinguished by its high carbon content and regenerative characteristics, rendering it an optimal resource for sustainable material production. By heating its biopolymers, lignocellulosic biomass can be used as a new material to make graphene, which forms three-dimensional turbostratic crystallites. These crystallites, composed of partially defective aromatic carbon sheets with graphite-like characteristics, make it easier to create GO with specialized functions for cutting-edge applications. Its capability underscores the revolutionary potential of biomass waste in …

Morphological Test Of Areca Nut Fiber Ceramic Membrane Using Scanning Electron Microscopy Energy Dispersive X-Ray Mapping Spectroscopy, Amelia Marzain, Siti Umi Kalsum, Marhadi Marhadi, Ahmad Nabil Shahab

Journal of Materials Exploration and Findings

This study investigates the potential of ceramic membranes derived from areca nut fiber as a cost-effective and environmentally sustainable material for the removal of iron (Fe) and manganese (Mn) from groundwater. Two types of membranes were fabricated: one without activation and one chemically activated using 10% sodium hydroxide (NaOH). The morphological and elemental characteristics of both membranes were analyzed using Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray (EDX) mapping. The concentrations of Fe and Mn before and after treatment were measured using Atomic Absorption Spectroscopy (AAS). The NaOH-activated membrane exhibited a more porous surface structure and higher oxygen content, …

Durability Of Alkali-Activated Concretes Under 5% Sulfuric Acid Environment, Celal Karabaş, Anıl Niş

Journal of Sustainable Construction Materials and Technologies

The investigation focused on the resistance to 5% sulfuric acid degradation of the alkali-activated concretes (AAC). The AAC was manufactured using a blended binder of 50% slag and 50% F-type fly ash. The AAC was activated using a blend of 14 M sodium hydroxide and sodium silicate, with a hydroxide-to-silicate ratio of 1/2,5. Six AAC were produced against a 5% sulfuric acid environment, varying the binder amounts (400–500–600 kg/m3) and activator-binder (A/B) ratios (0,45–0,55). The chemical resistance of AAC was evaluated by visual appearance, variation in weight and compressive strengths. The findings pointed out that more gypsum and higher weight …

Comprehensive Risk Assessment For Construction Site Managers In Kosovo: A Mixed-Method Approach, Muhamet Ahmeti, Besian Sinani

Journal of Sustainable Construction Materials and Technologies

This study developed and validated a hybrid ISO 31000:2018 Kosovo-compliant risk assessment framework tailored for construction site managers operating within transitional economies. The research employed audits of 20 ISO-certified contractors in Pristina, Kosovo, along with field observations, interviews, and quantitative risk matrices. The findings indicate a critical concentration of risk, with 70% of firms classified as "High" or “Very High” risk. The most prevalent hazards identified were working at height without collective protection, unprotected electrical systems, and manual handling of heavy materials. Regression analysis revealed that firms with a designated safety champion achieved significantly lower risk scores, whereas those with …

Behaviour Of Internally Strengthening Hollow Stainless-Steel Hot-Rolled Circular Columns Filled With Crumb Rubber And Recycled Aggregate Concrete, Wadhah M. Tawfeeq, Mohammed M. Rasheed, Mithaq Kohees, Ahmed W. Al Zandd, Saif Al-Balushi, Hamed Al Abdul Salam

Journal of Sustainable Construction Materials and Technologies

Stainless-steel sections are increasingly being utilised in favour of their higher durability. Simultaneously, the use of recycled materials in concrete is aligned with the global concern to encourage sustainable and environmentally friendly construction. The paper examined the behaviour of stainless-steel columns filled with concrete with crumb rubber (CR) and recycled aggregate (RA). It analysed the effect of different percentages of CR (0, 15, and 30) and RA (0, 15, and 50) on the compressive strength of the concrete and the performance of the columns using stainless-steel hollow sections. 20 specimens were manufactured, 18 of which were cast with concrete containing …

Piezoelectric Concrete: A Smart Material Approach For Energy-Harvesting Structural Technologies, Dianah Mazlan, Vynotdni Rathinasamy, Naveen Kumar, Liu Chunpeng, Elango Elango

Journal of Sustainable Construction Materials and Technologies

The rapid growth of urban infrastructure demands innovative materials that not only support structural performance but also contribute to sustainability through energy harvesting. Piezoelectric concrete, which integrates ceramics, polymers, nanomaterials, and bio-based fillers into cementitious matrices, has emerged as a promising solution. This review systematically explores the fundamentals of piezoelectricity in concrete, highlighting how stress-induced electromechanical coupling enables both energy harvesting and structural health monitoring. The paper critically evaluates major material systems including PZT ceramics, PVDF polymers, hybrid nanocomposites, and emerging bio-based materials, alongside their integration strategies such as embedded and surface-mounted approaches. Applications across pavements, bridges, and smart buildings …

Recovery Of High Energy-Value Materials From Mine Wastewater, Zainab Nasrullah

Graduate Theses & Non-Theses

The increasing global demand for high-energy-value materials (HEVM), such as rare earth elements (REEs), copper (Cu), nickel (Ni), cobalt (Co), and lithium (Li), coupled with their limited availability and environmental concerns associated with traditional mining methods, necessitates the development of alternative and sustainable recovery strategies. Wastewater streams from industrial processes, mining operations, and electronic waste treatment represent untapped reservoirs of these valuable materials. Research is proposed to develop sustainable, cost-effective, and scalable methods for selectively recovering HEVM from mine wastewater (Berkeley Pit, Montana). Two innovative approaches, the adsorption process using functionalized adsorbent and solvent extraction (SX) using organic or hydrophobic …

Recycling Ndfeb Magnets I: Production Of Ree Fluorides By A Novel Lpc Process, Isaac Joseph Cobbinah

Graduate Theses & Non-Theses

Neodymium-iron-boron (NdFeB) magnets account for over 60% of global magnet sales and are widely used in high-tech, military, and clean-energy applications (Ormerod, 2022). However, they contain critical rare earth elements such as Nd, Pr, and Dy which poses supply chain and geopolitical risks for country like the United States, which rely extensively on foreign sources. Recycling end-of-life NdFeB magnets provides a sustainable solution that diminishes environmental impact, strengthens supply security, and supports stable domestic production of important rare earth elements. A three-stage process has been developed for recycling the REE-content of NdFeB magnets. While the focus is on neodymium (Nd), …

Production Of Rare Earth Elements By Molten-Salt Electrolysis, Mohammed Moro

Graduate Theses & Non-Theses

Rare earth elements (REEs) are indispensable, high-value resources that play a crucial role in renewable energy, defense systems and advanced technological systems. REEs are commonly extracted from natural ores or recycled materials such as permanent magnets using hydrometallurgical or pyrometallurgical techniques. In hydrometallurgy, the REE source is leached with acid, followed by solvent extraction and precipitation steps to obtain rare earth compounds like oxides and fluorides. Pyrometallurgy involves dissolving rare earth compounds in a molten halide bath, followed by high-temperature electrolysis to convert them into metals, which are then recovered at the cathode. This process typically includes melting, refining, and …

Process Intensification For Rare Earth Elements Adsorption By Resonant Vibratory Mixing (Rvm), Mehran Saddat

Graduate Theses & Non-Theses

Rare earth elements (REE) are crucial to the advancement of modern technologies. REE applications include electronics, defense systems, wind turbines, catalysts, magnets, and aircraft. Bastnasite, monazite, and xenotime are the primary resources, while the secondary resources, including coal ash, E-waste, and acid mine drainage, are for REE extraction. The primary processing techniques are chemical leaching, ion exchange, chemical precipitation, pyrometallurgy, solvent exchange, biosorption, and adsorption. Adsorption technique is simple, cost-effective, and environmentally friendly, with higher efficiency but at the cost of a longer mixing time. Therefore, there is a pressing need for an optimized mixing technique to improve the adsorption …

Concerted Rattling-Induced Strong Anharmonicity And Phonon Coherence Lead To Ultralow Glasslike Thermal Conductivity In Tlagte, Shantanu Semwal, Yi Xia, Chris Wolverton, Koushik Pal

Mechanical and Materials Engineering Faculty Publications and Presentations

Ordered crystalline compounds exhibiting ultralow and glass-like thermal conductivity are both fundamentally and technologically important, where phonon quasi-particles dominate their heat transport. Understanding the microscopic mechanisms that govern such unusual transport behavior is necessary to unravel the complex interplay of crystal structure, phonons, and collective excitations of these quasi-particles. Here, we use state-of-the-art first-principles calculations based on quantum density functional theory to investigate the origin of experimentally measured unusually low and glassy thermal conductivity in semiconducting TlAgTe that possesses disconnected chains of Tl atoms within its three-dimensional crystalline framework made up of distorted AgTe4 tetrahedra. Utilizing a unifying framework of …

Study Of Isocyanate-Free Vegetable Oil-Based Polyurethane Coating With A Silicon-Based Compound For Coating Properties, Ajay Kumar

Electronic Theses & Dissertations

The development of sustainable and environmentally friendly polyurethane coatings has garnered significant attention in recent years. This research focuses on the development of isocyanate-free coatings derived from carbonated soybean oil (CSBO) using a solvent- and catalyst-free approach. The coatings were synthesized by reacting CSBO with ethylenediamine (EDA) and varying weight percentages of 3-aminopropyltriethoxysilane (APTES), which were added to enhance the coating property, as it contains silicon in it, to evaluate their mechanical and thermal properties. Fourier Transform Infrared Spectroscopy (FTIR) confirmed the successful formation of urethane linkages, with a significant reduction in C=O peak intensity after 10 days of curing, …

In-Situ Investigations Of Calcium-Magnesium-Aluminosilicates (Cmas) Infiltration Effects On Thermal Barrier Coatings Under Extreme Environments Replicating Jet Engines, Zachary Stein

Doctoral Dissertations and Master's Theses

Calcium-magnesium-aluminosilicate (CMAS) particulates, such as sand or volcanic ash, are ingested by gas turbine jet engines during operation. When operating within high abundance regions, these particulates negatively interact and degrade the high temperature thermal barrier coatings (TBC) protecting underlying superalloy turbine blades vital to engine operation. These CMAS particulates melt within the engine and infiltrate into the ceramic coatings. In electron-beam physical vapor deposited (EB-PVD) TBCs, the CMAS within the intercolumnar gaps stiffens the coatings and causes thermomechanical induced high stress concentrations, risking crack formation. While molten, the CMAS thermochemically alters and destabilizes the coating, also risking coating failure. Premature, …

Influence Of Build Plate Location On Tensile Properties And Residual Stresses In Lpbf-Fabricated Stainless Steel 316 Components, Yareli Zelaya Pavón

Honors Program Theses and Research Projects

Additive manufacturing (AM), particularly Laser Powder Bed Fusion (LPBF), enables rapid production of complex metal components with minimal waste. Stainless Steel 316 (SS316) is widely used in engineering applications due to its corrosion resistance and mechanical reliability. This study investigates the influence of build plate location on tensile properties and residual stresses in LPBF-fabricated SS316. Twelve tensile specimens and nine unsupported bridge structures were fabricated at different build plate positions using a “machine model.” Tensile testing provided stress-strain data to evaluate peak stress, elastic modulus, and strain at break, while bridge curvature measurements quantified residual stress through warping. Results indicate …

Building Enveloperetrofitting Innovation: Recycled Materials Role In Digital Fabrication And 3d Printing, Amr Soliman Elgohary, Haytham M. Elbadrawy, Ahmed Elsamanoudi

HBRC Journal

Traditional construction methods are one of the main causes of resource depletion. This research explores the intersection of digital fabrication methods using recycled materials and eco-friendly construction through retrofitting the building envelope to achieve sustainability. Traditional methods of retrofitting existing building elements consume many resources (materials-energy) and produce a lot of waste. In this context, 3D printing, a modern digital manufacturing method, stands out as a promising alternative, offering innovative ways to reduce material and energy consumption and reduce waste in the building construction process. This technique can be used to produce innovative modules that may improve the environmental performance …