Structural Engineering Commons^™

Evaluating The Effects Of Curing Methods On Bcsa Cement Concrete, Hannah Allen

Civil Engineering Undergraduate Honors Theses

BCSA cement is a type of cement that makes concrete set up much quicker than typical portland cement concrete. BCSA cement concrete also has a much higher compressive strength than that of portland cement concrete. This study was conducted to determine the effect of different curing conditions on the compressive strength of BCSA cement concrete.

Structural Design For Fire Conditions Of A Prototype Metal Building Using The New Proposed Appendix To Aisi S100, Xia Yan, Thomas Gernay

American Iron and Steel Institute (AISI) Specifications, Standards, Manuals and Research Reports (1946 - present)

Performance-based design for fire conditions has been increasingly adopted for different structural systems over the last decade. The objective of this project is to exemplify through a case study how the newly proposed Appendix 4 to AISI S100 [1] on ‘Structural Design for Fire Conditions’ could be used by the metal building industry. The scope of work on the project includes the following:

(1) Identification of a prototype metal building to serve as an exemplar case study for the structural fire design procedure.

(2) Definition of the performance objectives and design requirements for the building in the fire situation. This …

Semi-Annual Progress Report #10, Missouri University Of Science And Technology. Inspire - University Transportation Center

Semi-Annual Progress Reports

No abstract provided.

Control Strategy For Solar Energy-Saving Lamps For Optimized Energy Utilization And Sustainability Of Operation Durability: Indonesia Case, Burhanuddin Halimi, Agus Purwadi, Nana Heryana

Makara Journal of Technology

To solve the electrification ratio issue, the Indonesian government has promoted the use of solar energy-saving lamps. This study proposes a control strategy that adopts current reference time-based profiling for solar energy-saving lamps. For optimal energy consumption, the current reference profile is determined according to users’ daily energy requirements. From the aspect of user comfort, a gradual step reference profile is also introduced to provide a subtle change in lighting intensity level. The proposed control strategy can minimize energy consumption and optimize the operation durability of the system. The concept is verified by simulating four scenarios, the results of which …

Mechanical Behavior Of Clay Soil Stabilized With Fly Ash And Bottom Ash, Soewignjo Agus Nugroho, Azra Zulnasari, Ferry Fatnanta, Andius Dasa Putra

Makara Journal of Technology

Soil is one of the most important aspects of an infrastructure given its functions of receiving and holding structural loads. However, not all soils have good physical and mechanical properties. To overcome those conditions, stabilization of the soil is practiced to meet the technical requirements. This study aims to determine the behavior of high plasticity clay stabilized with lime, fly ash, and bottom ash. These additives can be used as a stabilizing agent to increase soil strength. The percentage of additives varied from 5%–25% then mixed with clay and were tested through the (Unconfined Compression Strength (UCS) test. The UCS …

Enhancement Of Biogas Production Through Solid-State Anaerobic Co-Digestion Of Food Waste And Corn Cobs, Lukhi Mulia Shitophyta, Anisa Salsabila, Firanita Angraini Putri, Siti Jamilatun

Makara Journal of Technology

Although biogas has been primarily produced through liquid anaerobic digestion, this method leads to the floating and stratification of fibers and non-homogeneous mixing, which can reduce the biogas yield. Alternatively, biogas can be produced by the solid-state anaerobic digestion (SS-AD) of organic material with a high solid content, such as corn cobs. We investigated the co-digestion of food waste and corn cobs as a biomass feedstock for SS-AD in biogas production. We measured the effects of the total solid (TS) content, percentage of food waste, and reduction in volatile solids (VS), from which we determined its appropriate kinetic model. We …

Structural Health Monitoring: From Virtual Shakers To Machine Learning, Ahsan Kareem

Abbett Distinguished Seminar Series

Structural health monitoring (SHM) is a critical means of assessing the performance of aging civil infrastructure. Earlier studies used heavy dynamic shakers to assess the dynamics of structures, which are unwieldy and reliance has been shifted to ambient vibration of structures to extract dynamic features. This study introduces a “virtual shaker” concept that effectively replaces the physical shaker and provides all the desired features for SHM. Examples are provided along with an App that facilitates the use of this concept to identify dynamic features. A traditional structural health monitoring (SHM) operation requires a wired system, which is often termed “hub …

Machine Learning-Based Bridge Load Posting Prediction, Sai Naga Sasi Aditya Bandaru

LSU Master's Theses

1600 (12%) of Louisiana's 13,000 bridges that allow the passage of people, goods, and services are load posted, meaning they are deemed incapable of securely carrying all legal loads. A machine learning framework for estimating the number of load-posted bridges within a regional bridge portfolio would be extremely valuable in the future for allocating essential resources during long-term planning. A framework of this type is necessary since a significant proportion of the bridges are load posted. Furthermore, deterioration due to aging and future increases in legal loads can compound this situation. In this setting, there is a lack of data-driven …

Machine Learning-Based Bridge Load Posting Prediction, Sai Naga Sasi Aditya Bandaru

LSU Master's Theses

1600 (12%) of Louisiana's 13,000 bridges that allow the passage of people, goods, and services are load posted, meaning they are deemed incapable of securely carrying all legal loads. A machine learning framework for estimating the number of load-posted bridges within a regional bridge portfolio would be extremely valuable in the future for allocating essential resources during long-term planning. A framework of this type is necessary since a significant proportion of the bridges are load posted. Furthermore, deterioration due to aging and future increases in legal loads can compound this situation. In this setting, there is a lack of data-driven …

A Case Study Of Protecting Bridges Against Overheight Vehicles, Aly Mousaad Aly, Marc Hoffmann

Faculty Publications

Most transportation departments have recognized and developed procedures to address the ever-increasing weights of trucks traveling on bridges in service today. Transportation agencies also recognize the issues with overheight vehicles’ collisions with bridges, but few stakeholders have definitive countermeasures. Bridges are becoming more vulnerable to collisions from overheight vehicles. The exact response under lateral impact force is difficult to predict. In this paper, nonlinear impact analysis shows that the degree of deformation recorded through the modeling of the unprotected vehicle-girder model provides realistic results compared to the observation from the US-61 bridge overheight vehicle impact. The predicted displacements are 0.229 …

Optimizing The Self-Healing Efficiency Of Hydrogel Encapsulated Bacteria In Concrete, Ricardo Hungria

LSU Master's Theses

Calcium carbonate precipitation through microbial means is a promising pathway for concrete self-healing technologies, mainly for its microcrack sealing attributes. The main goal of this project was to study and optimize the crack healing efficiency of hydrogel encapsulated bacteria in concrete. To achieve this purpose, Bacillus pseudiformus was implemented as the bacteria strain at a concentration of 10⁸ cells/ml. This bacterium strain along with yeast extract was combined along with three different mineral precursors corresponding to magnesium acetate, calcium lactate, and sodium lactate. All these three precursors were evaluated at two concentrations (67.76 mM/l and 75 mM/l). For each …

Cost-Efficient Bridge Scour Health Monitoring Using Commercial Sensors, Connor Embleau, Tien Yee, Metin Oguzmert, Mahyar Amirgholy, Alan Akazemi, Dale Goff

Symposium of Student Scholars

Bridge scouring has been a major international issue regarding bridge health and the overall longevity of a bridge. A common bridge health concern such as scouring accounts for close to 60% of bridge failures in the United States and is a leading cause to a bridge being in critical condition. Traditional methods to combat this failure is to measure the scour depth to assess a bridge health. Due to safety concerns of the traditional method, this study proposes to monitor a bridge’s health using a vibration-based technique. At present, vibration-based techniques have yet to be utilized reliably in the field. …

Fast Forest Fire Smoke Detection Using Mvmnet, Yaowen Hu, Jialei Zhan, Guoxiong Zhou, Aibin Chen, Weiwei Cai, Kun Guo, Yahui Hu, Liujun Li

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Forest fires are a huge ecological hazard, and smoke is an early characteristic of forest fires. Smoke is present only in a tiny region in images that are captured in the early stages of smoke occurrence or when the smoke is far from the camera. Furthermore, smoke dispersal is uneven, and the background environment is complicated and changing, thereby leading to inconspicuous pixel-based features that complicate smoke detection. In this paper, we propose a detection method called multioriented detection based on a value conversion-attention mechanism module and Mixed-NMS (MVMNet). First, a multioriented detection method is proposed. In contrast to traditional …

Reducing Early-Age Shrinkage Cracks Of Bridge Decks And Rails, Soumitra Das, George Morcous, Jiong Hu

UNL Student Research Days Posters, Graduate

Early-age shrinkage cracking of concrete bridge decks and rails accelerates the penetration of water and chemicals which leads to reinforcement corrosion, delamination, and eventually spalling. All this results in shorter service life, road closure, and costly repair. Development of Low-cement concrete(LCC) mix to reduce early age shrinkage crack through aggregate grading optimization was done in this research work. This approach also reduces concrete cost ($15-$20/cyd) (15–25%) and its carbon footprint (≈15%).

Evaluating The Effects Of Shored Construction On Steel Girder Composite Bridges, Parker Brooks

Doctoral Dissertations and Master's Theses

Steel composite girder bridges provide economic advantages and higher load-carrying capacity than non-composite alternatives. Over the years, a conventional sequence of un-shored construction for steel girder composite bridges has been developed. There is an alternative construction sequence, known as shored construction, that uses temporary supports (discretely or fully supported) for the superstructure during the installation of metal forms and the pouring of concrete. Shored construction also can be used in an Accelerated Bridge Construction (ABC) practice where construction occurs at a nearby site and fully-formed elements are transported to the final site using self-propelled modular transporters (SPMTs). In order to …

Monitoring Of Structural Quality Under Construction Using 3d Point Cloud Data, Xinxing Yuan

Civil Engineering ETDs

Inspection of infrastructure under construction has become an active research topic in the past few decades. Due to rising costs and safety concerns of current inspection methods, automated inspection methods are proposed. In this context, this dissertation has developed a framework that uses 3D point cloud data from the bridge under construction and evaluates the design specifications and the strength capacity of the structure while is being built. This study presents a slicing algorithm for automatically evaluating rebar placement using 3D point cloud data. The outcomes of this research provide structural engineering with (i) automatic inspection of reinforcement during construction; …

Toward Dexterous Aerial Manipulation Using Embodied Human-Intelligence For Bridge Inspection And Maintenance, Dongbin Kim

INSPIRE Archived Webinars

Current drones perform a wide variety of tasks in surveillance, photography, agriculture, package delivery, etc. However, these tasks are performed passively without the use of human interaction. Aerial manipulation shifts this paradigm and implements drones with robotic arms that allow interaction with the environment rather than simply sensing it. Many research groups have demonstrated aerial manipulation for various applications for over a decade. For example, in construction, aerial manipulation in conjunction with human interaction could allow operators to perform several tasks, such as hosing decks, drill into surfaces, and sealing cracks via a drone. This integration with drones will henceforth …

Bc-Dunet-Based Segmentation Of Fine Cracks In Bridges Under A Complex Background, Tao Liu, Liangji Zhang, Guoxiong Zhou, Weiwei Cai, Chuang Cai, Liujun Li

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Crack is the external expression form of potential safety risks in bridge construction. Currently, automatic detection and segmentation of bridge cracks remains the top priority of civil engineers. With the development of image segmentation techniques based on convolutional neural networks, new opportunities emerge in bridge crack detection. Traditional bridge crack detection methods are vulnerable to complex background and small cracks, which is difficult to achieve effective segmentation. This study presents a bridge crack segmentation method based on a densely connected U-Net network (BC-DUnet) with a background elimination module and cross-attention mechanism. First, a dense connected feature extraction model (DCFEM) integrating …

To Critically Review The Use Of Screencasts For Teaching Land Surveying, Eugen Niculae, Alain Chenaux

Conference papers

Screencasting tools allow for a screen capture of the actions on a computer screen with accompanying audio. This research initially reviews through the literature how screencasting has been used pedagogically and, through this primary research, the application of an existing screencast called Screencast-O-Matic and feedback from students from both Construction Management and Geospatial Surveying Undergraduate Programmes of TU Dublin, where and how it could be deployed for the surveying classes and fieldwork during the pandemic situation. This research occurred when all Irish third-level institutions lectures and tutorials moved online, and access to survey equipment for fieldwork was severely reduced. The …

Influence Of Phosphorus Sources On The Compressive Strength And Microstructure Of Ferronickel Slag-Based Magnesium Phosphate Cement, Cuirong Yan, Hongyan Ma, Zhongqiu Luo, Xintao Zhou, Luxing Wang

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Electric furnace ferronickel slag (EFS) is a typical magnesium-rich industrial by-product discharged from the manufacture of nickel and iron-nickel alloys. The approach to use it as the raw material for the preparation of magnesium phosphate cement (MPC) has potential and proves effec-tive. In this study, three different phosphorus sources (PS) including phosphoric acid (H₃PO₄, PA), sodium dihydrogen phosphate (NaH₂ PO₄, SDP) and potassium dihydrogen phosphate (KH₂ PO₄, PDP) were used to react with EFS to prepare the EFS-based MPC (EMPC), and the effects of raw material mass ratio (EFS/PA, EFS/SDP, …

Effects Of Long Duration Earthquakes On The Interaction Of Inertial And Liquefaction-Induced Kinematic Demands On Pile-Supported Wharves, Milad Souri, Arash Khosravifar, Stephen E. Dickenson, Nason Mccullough, Scott Schlechter

Civil and Environmental Engineering Faculty Publications and Presentations

Nonlinear dynamic analyses were performed to evaluate the effects of ground motion duration on the dynamic response of a pile-supported wharf subjected to liquefaction-induced lateral ground deformations. The numerical model was first calibrated using recorded data from a well-instrumented centrifuge test, after which incremental dynamic analyses were conducted using a suite of spectrally matched motions with different durations. The nonlinear dynamic analyses were performed to evaluated three loading scenarios: combined effects of inertial loads from the wharf deck and kinematic loads from ground deformations, deck inertial loads only in the absence of liquefaction (with minimal kinematic loads), and kinematic loads …

Resilient Modulus Of Siliciclastic Unbound Granular Materials Under Repeated Wheel Loading, Siya Rimoyi

Tanzania Journal of Engineering and Technology (TJET)

The Resilient Modulus (Mr) is a fundamental material property input in modern Mechanistic-Empirical (M-E) pavements structural design. Empirical pavement design methods have been in use over a long period during which large databases of four- days-soaked California Bearing Ratio (CBR) values at or near the Maximum Dry Density have been generated in the strength assessments for Unbound Granular Materials (UGMs). In the adoption of the M-E design approach researchers have so far attempted with various degrees of success to develop models to derive resilient modulus from the conventional CBR-based databases. This study provides an extensive laboratory experimental study to investigate …

Blast Analysis Of Steel-Plate Composite Slabs: Sdof And Fem Analyses, Joshua R. Harmon, Amit H. Varma

Bowen Laboratory Research Reports

Steel-plate composite (SC) members have emerged as competitive construction methods for tall buildings and nuclear power plants. Detailed design guidance has been created for these functions and design of these members is now covered in AISC 341-16 and ASIC N690-18. However, SC members are emerging for use in protective structures to withstand blast and impact loads. Although experimental tests of SC members for blast resistant design have been conducted, design of SC members for blast loads has not been addressed in existing design references for blast loadings (UFC 3-340-02). This report details a general design philosophy for blast loaded SC …

Setting Times Of Early-Age Mortars Determined From Evolution Curves Of Poisson’S Ratio, Bate Bate, Xiao Chen, Chao Chen, Hongyan Ma, Jianfeng Zhu, Junnan Cao, Jiakai Chen, Kamal Khayat, Shuai Zhang

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Setting times, as the early-age properties of cement-based materials, are important properties to ensure the quality and long-term performance of engineering structures. To determine the initial and final setting times of cementitious materials, the compressive wave velocity and shear wave velocity of six early-age mortar samples were monitored. Their time evolution curves of Young's modulus, shear modulus, bulk modulus, and Poisson's ratio were then calculated and analyzed. The signature times of the derivatives of the Poisson's ratio evolution curves correlate well with the initial and final setting times, and the remarkably high coefficient of determination values relative to the data …

Flexural Strengthening Of Rc Slabs Using Near Surface Mounted Gfrp Bars, Sama Taha

Theses and Dissertations

Glass Fiber reinforced polymers (GFRPs) have been recently successfully used to increase reinforced concrete elements' strength. In general, FRPs have many advantages such as resistance to corrosion, and high strength-to-weight ratio. On the other hand, debonding from concrete may constitute a limitation to using GFRP bars; hence the increase in strength of RC elements strengthened using GFRP bars may be limited by this premature debonding failure mechanism.

This study aims to investigate the strengthening effect of GFRP bars on the capacity of RC slabs when subject to flexure loading. The work studies the use of different bonding lengths, diameters and …

Strengthening Of Long Rc Columns Using Near Surface Mounted Gfrp Bars, Ahmed Romaih

Theses and Dissertations

Many of the existing reinforced concrete (RC) columns are deficient because of numerous reasons such as increase in service loads, deterioration due to environmental attacks, errors in the design and/or construction phase or in the worst case, accidents. These elements require strengthening or repair. Different methods have been developed over the years for solving different rehabilitation problems. Recently, advanced composites used for external bonding in the form of fabrics or laminates have become an accepted method. The use of Fibre-Reinforced Polymers (FRPs) in this process is a promising technology, especially that these materials are corrosion-free. One of the new techniques …

Numerical Assessment Of Post-Tensioned Slabs Due To Seismic Column Collapse, Mariam Ehab, Aya Elhozayen

Civil Engineering

In our recent catastrophes, Progressive collapse become an essential behavior that should be researched widely and to be considered by engineers through the design process. The main vertical loss can be caused by different reasons, either blast due to terrorist attack, failure of columns due to extreme earthquake application, or finally, losing a structural element due to high impact resulted from a vehicle or any other moving object. Losing main vertical element due to extreme earthquake excitation is an important and repeated occurrence, However, it didn’t take much attention in progressive collapse recent studies. Unified Facilities Criteria (UFC) and General …

An Examination Of Effective Length In Moment Frames, Connor Stephen Schott

Honors Theses and Capstones

The honors thesis project I have been working on is called An Examination of Effective Length in Moment Frame. When loaded axially in compression columns experience a failure mode in compression that axially loaded members don’t experience in tension. This failure mode, elastic column buckling, doesn’t involve yielding or rupture; the column changes shape and deforms to the side. In order to come up with a solution to this failure mode, Leonhard Euler developed the critical buckling load equation. However, this equation uses an effective length of columns, which is the distance between two points of zero moment, or …

North 14th Street Corridor Improvements Project, Ashley Nguyen, Samantha Corey, Maricela Paramo Reyes, Pooja Rajeev

Honors Program: Senior Projects (Public)

The following project report was a study of the North 14^th Street corridor ranging from Adams Street to Virginia Street conducted by University of Nebraska-Lincoln students for a senior design capstone project. Main focuses of the project were the intersection of Adams and 14^th Street and the 14^th Street bridges over Cornhusker Highway and Oak Creek. Study of this area included work in transportation, traffic, structural, geotechnical, water resources, and environmental engineering. However, this report done by students should not take the place of work done by licensed professional engineers.

This project was done in collaboration with …

Analysis Of Shear Failure In Ultra-High Performance Concrete Beams, Kevin Conway

Electronic Theses and Dissertations, 2020-2023

Ultra-high performance concrete (UHPC) is an emerging cementitious material type currently undergoing research in different structural applications. This material is characterized by a compressive strength of 150 MPa (22 ksi), according to the Association Francaise de Genie Civil and the Federal Highway Administration, high tension strength, and high durability. Additionally, UHPC consists of secondary reinforcement in the form of steel or polymeric fibers, which enable UHPC to exhibit tension hardening behavior and tension ductility previously ignored in conventional concrete mixes. Previous research has focused on applications in the transportation and bridge design industries; however, applications in buildings and other heavy …