Structural Engineering Commons^™

Voltage-Related Power Quality Issues And Impacts On Distribution Networks With Sensitive Loads - A Review, Godwin Elinazi Mnkeni, Jackson Justo, Aviti Thadei Mushi, Bakari M. M. Mwinyiwiwa

Tanzania Journal of Engineering and Technology (TJET)

Voltage disturbances are the most important power quality (PQ) complications that customers and power utilities face in this smart era. The growing adoption of sophisticated electronic equipment and integration of renewable energy sources (RES) into power grids has increased the susceptibility of power distribution networks (PDNs) to voltage sags, swells, interruptions, flicker, and voltage imbalance. These disturbances, mainly caused by upstream faults, switching operations, and RES integration, compromise voltage PQ and system reliability. Consequently, they accelerate equipment degradation, increase electronic waste (e-waste), raise reactive power demand and maintenance costs, increase power losses, and impose substantial economic losses on customers and …

Improving The Concrete Compressive And Flexural Strength With A Low Fraction Addition Of Carboxylated Nitro-Oxidized Cellulose Nanofibrils From Banana Rachis, Ngesa Ezekiel Mushi, Emmanuel Kagya

Tanzania Journal of Science

Conventionally, concrete strength depends on the bonding interface, especially in hydrated products such as calcium silicate hydrate (CSH). As a result, concrete is sensitive to tensile load. With its unique properties, a low fraction of carboxylated nitro-oxidized cellulose nanofibrils (NOCNF) from the banana rachis is employed to improve the mechanical performance of the concrete nanostructurally. Compressive and flexural strength using the NOCNF content at 0, 0.05, and 0.1 wt.%, cured for 7 and 28 days, were evaluated. Notably, the compressive strength increased by 16 % and the flexural strength by 13 % at 0.1 wt.% NOCNF compared to plain concrete …

Experimental Studies Of Compressive Strength Of Sustainable Concrete With Partial Cement Substitution Using Palm Oil Boiler Ash, Daral Suraedi, Jessica Sjah, Nuraziz Handika, Saffanah Fasya Aulia, Karmenita Olivia Edwardo

CSID Journal of Infrastructure Development

This study investigates the mechanical performance of sustainable concrete incorporating Palm Oil Boiler Ash (POBA) as a partial cement replacement. As the construction sector seeks to reduce CO₂ emissions and manage agro-industrial waste, POBA emerges as a promising supplementary cementitious material due to its pozzolanic potential and abundance in palm oil–producing regions such as Indonesia.Concrete specimens were prepared with POBA substitution levels ranging from approximately 10% to 30% by weight of cement, in combination with nanosilica and a polycarboxylate ether (PCE) superplasticizer to enhance performance. The mix design was developed in accordance with ACI 211 guidelines to maintain comparable workability …

Comparative Study Of Cement-Rice Husk Ash Stabilized Bricks And Fired Clay Bricks, Daniel R. Samson, Emmanuel S. Leo

Tanzania Journal of Science

In some countries, fired clay bricks (FCBs) are widely used for construction, but their production is energy-intensive, relies largely on firewood, and contributes to deforestation and carbon emissions. This study explores unfired clay bricks stabilised with cement and rice husk ash (RHA) as a sustainable alternative, using Dakawa ward in the Morogoro Region, Tanzania, as a case study. The bricks, with a clay of plasticity index 17%, were stabilized with 6%, 10%, and 14% cement by mass, moulded into 40 mm cubes, and cured for 28 days. The compressive strengths achieved were 1.5, 3.6, and 4.1 MPa with water absorption …

Impact Of Femalized Kinesthetic Learning Model On African American Middle School Girls’ Career Interest, Mercy F. Fash, Andrea Ofori-Boadu

Journal of Global Education and Research

Engaging African American middle school girls in out-of-school-time (OST) Architecture, Engineering, and Construction (AEC) programs can boost interest in male-dominated AEC careers. This study adopts Lent’s Social Cognitive Career Theory to evaluate the impact of an OST feminized AEC kinesthetic learning model (fAEC-KLM) on the career interests of this demographic. Through a qualitative research approach, fourteen (14) African American middle school girls from Guilford County, NC, completed pre- and post-interviews on how fAEC-KLM interactions influenced their AEC career interests. Inductive thematic analysis was carried out on transcribed interviews. Results show that effective components, such as lectures on AEC, bridge construction …

Smart Dynamic Concrete: Effect Of Coarse Aggregate Size Distribution On Fresh, Mechanical And Durability Properties, Venu Sipelli, Kamineni Aditya, Shravya Sripadapu

Mansoura Engineering Journal

SDC is a self-flowing concrete that demonstrates improved material efficiency through optimized aggregate gradation. Unlike SCC, which relies on high powder content for improved flowability, SDC provides improved flowability by optimized aggregate gradation, making it a promising alternative to SCC. This paper presents the fresh, mechanical, and durability performance of M40-grade SDC using OPC 53 grade cement, GGBS, CRF, and polycarboxylate-based superplasticizer. A constant cementitious content of 470 kg/m³ and water–cement ratio of 0.38 were maintained. The fresh, mechanical, and durability performances of SDC using three types of coarse aggregate combinations, namely, 70% 10 mm + 30% 20 mm, 75% …

Enhancing Health And Safety Practices In Construction Site In Developing Nations Through Technology Advancement In South Western Nigeria, Mubaraq Lawal, Abba Mahmud, Ismail Gbolahan Dere, Thankgod Agbo Owoicho

CSID Journal of Infrastructure Development

The construction sector plays a critical role in urban development and economic growth, yet it continues to face major challenges that threaten worker health and safety. Traditional safety measures are not always sufficient for the complex conditions found on construction sites, which creates a need for technology‑based solutions. This study investigates the relationship between technology adoption and health and safety practices in the construction industry in Lagos, Nigeria. The study identifies the major causes of site accidents, examines the level of technology use on construction sites, and reviews existing literature through both primary and secondary data. Primary data were collected …

The Use Of Local Materials For The Interior Quality Of Swahili Building Design In Tanzania, Luiana Makundi, Jacob Lutta

Tanzania Journal of Engineering and Technology (TJET)

Swahili architecture in Tanzania is recognized by spatial capacity to adapt environmental changes. This research explores the role of locally available materials in shaping the interior quality by focusing on functional, aesthetic appeal and supporting sustainable environment. A mixed-methods approach was applied which, involves field surveys, case study and interviews with different local professionals in building industry. Dar-es-Salaam was used as a case study area that was critically analysed to identify construction practices and applications of local materials in building interior spaces. A particular focus was placed on materials durability, aesthetic, ecological, environmental balance and thermal efficiency which seems to …

From The Editors, Rully Karim Dr.

Journal of Project Management & Construction

The Journal of Project Management and Construction (JPMC) is a peer-reviewed publication dedicated to advancing the field of project management and construction, grounded in the principles outlined in the PMBOK 6th Edition. Our focus encompasses the ten knowledge areas essential to successful project management: Integration, Scope, Schedule, Cost, Quality, Resource, Communications, Risk, Procurement, and Stakeholder Management.

JPMC publishes original research papers written in English that provide deeper insights into these knowledge areas and contribute to the development of best practices in project management and construction. Submissions may include theoretical analyses, computational models, experimental observations, or a combination of both theoretical …

Assessment Of Safety Monitoring Indexes Of High Rcc Gravity Dams Considering Hydraulic Fracture, Mohamed Ramdan, Jinsheng Jia Professor, Xu Li Professor

Journal of Engineering Research

High concrete gravity dams, particularly Roller-Compacted Concrete (RCC) types, face long-term safety challenges due to weak interlayer formation and crack propagation. This study presents a comprehensive evaluation of safety monitoring indexes for the Guxian high RCC dam (currently under construction in China) using both numerical and theoretical models. A Finite Element Method (FEM) was applied with two approaches: the strength reduction method, which considers weak layers, and the overloading method, which simulates extreme loading without accounting for material degradation. A comparative analysis between these two methods was conducted to determine which more effectively evaluates dam safety under varying conditions. Additionally, …

Flexural Behavior Of Sustainable Concrete Beams Containing Waste Tire Fibers And Recycled Aggregates, Wael M. Montaser Ass.Prof

Journal of Engineering Research

The increasing accumulation of diverse waste materials poses a significant societal challenge, highlighting the importance of developing methods to reuse such waste effectively. One promising solution involves incorporating recycled coarse aggregate (RCA) obtained from demolished concrete into new concrete mixtures. Additionally, tire-derived fibers (TDF), sourced from recycled tires, present an environmentally friendly substitute for conventional reinforcement materials. The integration of RCA with TDF in reinforced concrete beams offers a sustainable approach to enhancing structural performance. This experimental study investigates the flexural performance of reinforced concrete beams containing recycled coarse aggregate (RCA) and tire-derived fibers (TDF). Four mixes with varying RCA …

The Influence And Firing Of Zircon, Ilmenite, And Magnetite As Partial Sand Replacement On The Properties Of Concrete For Specialized Applications., Samy A. Fawzy

Journal of Engineering Research

This study investigates the impact of partially replacing sand with varying percentages (10%, 20%, 30%, and 50%) of zircon (ZrSiO4), ilmenite (FeTiO3), and magnetite (Fe3O4) on the physical and mechanical properties of concrete. The research focuses on evaluating the compressive strength, density and radiation shielding capabilities of the modified concrete mixtures. The effect of firing concrete cubes(600,900 and 1100 C) with various percentages of the three materials were studied also. The use of these heavy minerals aims to enhance concrete properties for specialized applications such as radiation shielding structures and high-density construction. Results indicate that increasing the replacement percentage of …

Machine Learning-Based Prediction Of Load Capacity In Corrugated Concrete-Filled Double Skin Tubes Under Axial Load, Aya Mohsen Handousa Mansoura University, Fikry Salem, Nabil Mahmoud Mahmoud, Mohamed Ghannam

Journal of Engineering Research

Concrete-filled double-skin steel tubular (CFDST) columns have become widely utilized in building construction and bridges, thanks to their exceptional structural capabilities. This study investigates the axial compression behavior of corrugated CFDST columns, analyzing the impact of flat or corrugated external/internal plates and varying internal steel tube widths. Furthermore, basic regression analysis fails to precisely forecast the complicated relation between the column properties and their compressive strength. To overcome these challenges, this study suggests two machine learning (ML) models, including the Gaussian process (GPR) and the extreme gradient boosting model (XGBoost). To estimate their strength, these models employ a range of …

A Comprehensive Review Of Carbonation In Supplementary Cementitious Concrete: Factors Affecting, Measurement Methods, And Challenges, Mariam Farouk Ghazy, Metwally Abd Allah Abd Elaty, Esraa Samir Abdeljalil

Journal of Engineering Research

Abstract-After water, concrete is the most widely used material on the planet. Accelerated carbonation treatment is an effective approach of reducing carbon emission in the concrete industry. Such carbonation process converts gaseous CO2 into carbonated minerals. This review provided a special focus on internal and external variables affecting carbonation depth. Internal variables such as mixture components, External variables such as adding pozzolanic materials such as fly ash, and slag were examined systematically, temperature, pressure, and CO2 concentration. The effect of accelerated carbonation curing on the compressive strength of concrete at early ages, both positive and negative influences were identified. …

Structural Performance Of Corrugated Steel Plate Shear Walls, Eyad Ayman Bakry, M. F. Hassanein, Ayman Seleemah

Journal of Engineering Research

Abstract- Corrugated Steel Plate Shear Walls (CoSW) represent a groundbreaking advancement in structural engineering, providing exceptional seismic resilience, energy dissipation, and lateral stiffness compared to traditional flat steel plate shear walls. This paper offers a comprehensive review of CoSW performance under various conditions, including cyclic and seismic loads, with a focus on enhancing geometric configurations and reinforcement techniques. Key innovations such as enhanced corrugation angles, stiffener integration, and strategically designed openings are discussed. Recent progress in computational modeling and experimental validation has further refined design methodologies, ensuring their practical applicability. The review highlights that critical parameters such as corrugation depth, …

Numerical Investigation Of Thermal Effects On Concrete Bridges: Insights From Frame And Shell Modeling, Mohamed Ibrahim Metwally Dr., Mohamed A. El Zareef Prof.

Journal of Engineering Research

Bridges are essential structural components of transportation networks, and their performance is significantly influenced by temperature variations. Thermal expansion and contraction can induce stresses that affect structural stability, necessitating accurate modeling techniques for design and maintenance. This study investigates the thermal behavior of a three-span continuous box girder bridge using two different numerical modeling approaches: the Frame Element model and the Shell Element model. The research evaluates the effects of uniform temperature conditions (20°C) and a temperature gradient of ±5°C, focusing on bending moments, normal forces, and fiber stresses. Results indicate that the Shell Element model predicts bending moments and …

Finite Element Modeling Of Newly Developed Cold-Formed Hollow Flanged Z-Beams, Mohammed Ahmed Diab, Mohamed Saeed Refaey, Hanan Eltobgy

Journal of Engineering Research

Cold-formed hollow flanged sections (CFHFS) are considered an innovative advancement in cold-formed steel design. These sections offer large lateral torsional rigidity over the open cold-formed section resulting in enhanced flexural capacity. This paper introduces a numerical study on the section moment capacity of newly developed cold-formed hollow flanged Z-beams (CFHFZBs). CFHFZBs can be easily constructed in the Egyptian market by welding an industrially available main Z-element to two secondary Z-elements to form the hollow flange. This paper presents the finite element modeling of sixteen CFHFZBs in a four-point bending arrangement using ABAQUS software. To obtain verified finite element models (FEMs), …

Investigating The Properties Of Eco-Bricks Composed Of Sawdust, Bamboo, And Varying Composition Of Sugarcane Bagasse Ash And Portland Cement, Wilfred Victor C. Marasigan, Julia Sophia Antonia S. Encarnacion, Czyrus Michael A. Bajeta, Alijah F. Gonzales, Juan Carlo T. Gumangan

Sinaya: A Philippine Journal for Senior High School Teachers and Students

With the construction industry contributing nearly 40% of global greenhouse gas emissions, there is a growing need for innovative and sustainable building materials. This research investigates a new eco-friendly concrete brick incorporating sugarcane bagasse ash (SCBA), sawdust, and bamboo fibers. Three eco-brick mixtures, each containing 2% bamboo fiber and 10% sawdust by weight but with varying proportions of Portland cement (PC) and SCBA, were tested against a standard brick for compressive strength, flexural strength, and water absorption. The optimal mixture, with 2% bamboo fiber by weight, 10% sawdust by weight, 85% PC, and 15% SCBA, exhibits compressive and flexural strength …

Ultimate Limit State Reliability-Based Approach Life Prediction Of An Existing Frame Structure Under Seismic Hazard In Indonesia, Wira Herucakra, Luh Putri Adnyani

Journal of Materials Exploration and Findings

Life assessment integrated with Structural Integrity Management (SIM) has been implemented in the oil and gas industry for the past decade to maintain the integrity and safety of an in-service structure used to support hydrocarbon exploration, production, and processing activity. Current structural life assessment, as ruled by the American Petroleum Institute (API), uses a fatigue-based approach for offshore structures subjected to wave loading. As the general principle of SIM is not limited to offshore structures, this study offers an alternative life assessment method for onshore structures, especially steel frame structures subjected to earthquake loads. Reliability analysis, combined with the effect …

Comparative Analysis On Design Error Risks In Design-Bid-Build And Design-Build Construction Approaches, Eradius Edward Rwakarehe

Tanzania Journal of Engineering and Technology (TJET)

This study was conducted to compare design errors risk in Design-Bid-Build (DBB) (traditional) and Design-Build (DB) methods in building projects. Several construction projects under both DB and DBB method were reviewed. On most of construction projects under DB method, it was found that there were over supply of floor area due to different reasons. Also, it was found that, clients’ requirements were changed during project execution, which resulted into change on schedule, contract value and project quality. It was also revealed that in most cases, designs were in accordance with the clients’ requirements as submitted earlier but during construction clients …

Experimental Investigation Of Multi-Cell Column Foun-Dations Under Bending Loads, Mostafa Abdo Abdllah Sharp

Journal of Engineering Research

This study investigates the structural behavior of connections between multi-cell columns and foundations under bending loads. The term "multi-cell" refers to sections with multiple longitudinal hollow cores separated by thin webs. A total of eight specimens were modeled and analyzed using the finite element software ABAQUS/CAE [1], under a single loading line system until failure. To facilitate this study, a control specimen was created as a benchmark, enabling the assessment of various parameters' impact on the connection. These parameters include embedment depth, the number of cells in the column, the presence of shear studs, internal plates, and concrete infill within …

The Performance Of Different Systems In Resisting Seismic Loading For High Rise Concrete Structures, Samy A. Fawzy

Journal of Engineering Research

High-rise buildings are subjected to gravity and mostly lateral loading from seismic and wind loads that affect the behavior of such structures. In this study, we will deal with the seismic behavior of different concrete systems. Moment resisting frame, Shear wall, global bracing and dual system are used in this study. A 3D model in static and dynamic analysis was done using ETABS software then a pushover analysis and a parametric study as well for different systems. The study proved that the case of moment resisting frame is the worst in resisting displacements and drift as well. Although the model …

Numerical Analysis Of Cold-Formed Built-Up Battened Steel Columns Under Eccentric Compressive Loading, Mai Mohamed Sheta, Hanan Hussein Eltobgy, Mohamed Massoud El Saadawy, Khaled Abdallah Gharib

Journal of Engineering Research

This paper presents a 3D finite element model simulation using ABAQUS finite element software to investigate the behavior of steel battened beam columns under uniaxial loads. The columns consist of double-channel cold-formed slender open sections. The study highlighted the effects of various factors on the ultimate capacity of these beam-column members.

By considering both global and local imperfections, the model focuses on the structural strength and performance of battened cold-formed steel columns made from built-up sections. These cold-formed steel (CFS) columns have a slenderness ratio ranging from 50 to 162. Axial loads are applied at the pin-ended support of the …

Non-Linear Analysis Of Axially Loaded Built-Up Open Section Cold-Formed Columns, Mai Mohamed Sheta, Hanan Hussein Eltobgy, Mohamed Massoud El Saadawy, Khaled Abdallah Gharib

Journal of Engineering Research

Built-up open cold-formed sections are commonly used in entrances, structural corners, and window frames. These elements exhibit low torsional stiffness and are highly susceptible to cross-sectional deformation. Battened built-up cold-formed steel (CFS) open columns offer enhanced load-carrying capacity when individual profiles cannot withstand applied loads.

Extensive research has focused on understanding the buckling behavior of these structural elements. However, limited studies have explored the impact of spacing between cold-formed C-channel sections. Existing research suggests that battened columns with adequately spaced members exhibit superior structural performance compared to those with closely spaced channels.

A critical factor affecting the performance of battened …

Numerical Study For Strengthening Hexagonal Castellated Steel Beams Using Hexagonal Ring Stiffeners, Amany M. Morad, Omnia F. Kharoub, Nashwa Yossef

Journal of Engineering Research

This paper investigates numerically how the castellated steel beams are affected by the addition of hexagonal stiffeners around hexagonal web openings. Increasing the CSBs' load-bearing capacity and improving their overall structural behavior are the main objectives of this strengthening technique. Although there are different failure modes as a result of castellation, the main emphasis of this study is web post-buckling. Using ABAQUS software, a 3D finite element model is created to analyze the beam's behavior. The model's accuracy was validated by comparing its results with those from previous experimental studies. Failure loads, failure modes, and load-deflection curves of CSBs are …

Design Of An Electro-Hydraulic Laboratory Test System For Adjusting The Inclination Angle Of Sowing Machines, Aytac Moralar, Figan Dalmis, Bahattin Akdemir

The Philippine Agricultural Scientist

Field testing of grain sowing machinery requires favorable field conditions and sufficient time periods, making laboratory tests a preferred alternative for determining performance under controlled conditions. However, a standardized testing system for evaluating sowing machinery has not yet been established. In this study, a test system was designed for laboratory testing of universal grain sowing machines. A movable platform was built on a chassis made using sheet metal with different dimensions and profiles. It operates through a hydraulic system via a programmable logic controller-based control system. The sowing machine placed on this platform allows for inclination adjustments (front, back, right, …

Optimization Of The Cross-Section Of Generic Flexible Bridges, Manal Kamal Zaki, Mina M. Helmy, Mark M. Tawadros

Journal of Engineering Research

This paper investigates the behavior of flexible bridges prone to aerodynamic instabilities due to wind. Optimal cross-sections that reduce aerodynamic forces are recommended. This is achieved by studying a variety of bridge sections with different widths of upper and lower sloping edges in addition to studying the upper and lower cramps of the deck. The wind velocities are also parameterized. Computations are developed based on the powerful computational fluid dynamics (CFD) method known as FLUENT and embedded in ANSYS software. For parametric study, a design of experiments (DOE) is performed based on the response surface methodology (RSM) combined with the …

Preliminary Spectral Matching Analysis Of The Rod El-Farag Region In Cairo, Egypt, Ahmed F. Youssef, Amr Z. Elkady, Ayman A. Seleemah

Journal of Engineering Research

Abstract: Earthquake engineering assessments are essential for evaluating the seismic response of structures. Nonlinear dynamic analysis is a highly effective method for evaluating seismic re-sponse, considering the complex, three-dimensional, and dynamic behaviour of structures during earthquakes. The complexity of seismic damage assessment arises from ground motion and struc-tural modelling parameters. Spectral matching is a key method in seismic codes and aids in selecting earthquake accelerograms for performance- and force-based designs. Spectrum-matched data is increasingly used to estimate nonlinear structural responses. Spec-tral matching utilizes the wavelet adjustments introduced by Abra-hamson (1992) and refined by Hancock et al. (2006) to adjust earth-quake …

Optimizing And Validation Of Sustainable Uhpc With Waste Glass Powder Utilizing Modified Particle Packing Approach And Response Surface Methodology, Mohamed Taman, Elsaid Maaty, Alaa Mehrez, Ahmed Kamal Isaac

Journal of Engineering Research

The current study explores the potential of utilizing Waste glass powder (WGP) as an alternative to cement in the development of sustainable eco-friendly Ultra-high-performance concrete (UHPC). UHPC mixtures underwent optimization through the application of a Modified Andreasen and Andersen (MAA) particle packing model, resulting in a reduction of cement content from 900 to 800 kg/m³. Six mixes were cast, with varying levels of cement replacement ratios with WGP up to 50%. The evaluation focuses on the flowability, dry density, and mechanical properties of UHPC at different ages using normal curing. A statistical model utilizing response surface methodology (RSM) …

Improved Minimum Variance Channel Estimation Techniques For Ofdm Systems, Kwame S. Ibwe

Tanzania Journal of Engineering and Technology (TJET)

Orthogonal frequency division multiplexing (OFDM) systems face challenges in channel estimation due to noise, variability, and the doubly dispersive nature of wireless channels, which degrade performance. To address these challenges, a multichannel minimum variance double dispersive channel estimator is proposed. The method employs a hybrid approach that combines subspace and minimum variance techniques, optimizing the filter bank output power under a signal-to-noise ratio (SNR) constraint. This design preserves the desired signal while effectively suppressing disturbances, achieving robust performance with reduced computational complexity compared to existing methods. Simulation results demonstrate that the proposed estimator outperforms subspace and asymptotic methods in terms …