Structural Engineering Commons^™

Process Optimization And Quality Control In Manufacturing Of Frp Composites By Vartm, Mohamed Emadeldin Omar Abdelhadi

Graduate Theses, Dissertations, and Problem Reports (ETD)

Railroad tank cars, being one of the most used means of transportation of hazardous material across the country, have not been structurally upgraded for a long time. Thus, the Pipeline and Hazardous Materials Safety Administration (PHMSA), a United States Department of Transportation (USDOT) agency, released a rule for safer transportation of highly hazardous and flammable liquids by railroad to enhance the design specifications of both the new and existing tank cars in May 2015. A multifunctional composite jacket is proposed as a new material to structurally enhance the railroad tank cars to withstand any accidents that could happen en route. …

In-Plane Shear Stiffness Of Stay-In-Place Forms And Bracing Effects On The Torsional Stability Of Press-Brake-Formed Tub Girders, Ethan L. Host

Graduate Theses, Dissertations, and Problem Reports (ETD)

Press-brake-formed tub girders have welded internal angle bracing that is believed to be necessary for torsional stability under eccentric loading. However, this bracing creates fatigue weld hotspots overtime, which are subject to cracking. This study was performed to assess the torsional behavior of the Valmont U12 press-brake-formed tub girder (PBFTG) under various configurations using finite element analysis (FEA) modeling and experimental laboratory testing. The primary objective was to (1) determine the necessity of various angle bracing throughout the beam, and the effects removing said braces has on the torsional stiffness of the girder and (2) investigate the use of stay-in-place …

Influence Of Deck Area And Average Daily Traffic On The Deterioration Of Bridge Superstructures., Faysal Ahamed

Graduate Theses, Dissertations, and Problem Reports (ETD)

State Departments of Transportation (DOTs) are responsible for maintaining approximately 623,000 bridges across the United States. Effective bridge management requires a comprehensive understanding of the factors influencing structural deterioration. Numerous studies have explored the effects of average daily traffic (ADT) and deck area (DA) on bridge deck deterioration. Given the interdependence between bridge decks and superstructures, it is plausible that ADT and DA significantly influence superstructure condition ratings and deterioration trends. However, their impact on superstructures remains insufficiently studied. In addition, existing studies primarily focus on overall bridge deterioration without adequately differentiating between superstructure designs and materials and maintenance authorities. …

Reuse Of Calcium Carbonate (Caco3) Recovered From Discarded Carpets As Filler In Fiber-Reinforced Polymer (Frp) Composites, Roshan Devkota

Graduate Theses, Dissertations, and Problem Reports (ETD)

Over four billion pounds of carpet are discarded annually in the United States, making carpet waste a significant environmental concern. Calcium carbonate (CaCo₃) constitutes up to 45% of the mass of most synthetic carpets. Reusing this CaCo₃ as a filler in the rapidly growing fiber-reinforced polymer (FRP) industry, which is projected to reach USD 10.38 billion, presents a low-cost, practical approach to developing a market-based solution to post-consumer carpet waste.

This study investigates the reuse of CaCo₃ recovered from discarded carpet backing as a filler in FRP composites, focusing on its mechanical viability in comparison to virgin CaCo₃. The methodology …

The Impact Of Skew On The Flexural Behavior Of Press-Brake-Formed Tub Girders, Matthew Allan Weatherholt

Graduate Theses, Dissertations, and Problem Reports (ETD)

The Short Span Steel Bridge Alliance (SSSBA) is a group of bridge and buried soil steel structure industry leaders who have joined together to provide educational information on the design and construction of short span steel bridges in installations up to 140 feet in length. Press-brake-formed-tub-girders (PBFTGs) were developed by a technical working group within the SSSBA in response to a rising demand for rapid infrastructure replacements for short span bridge applications. PBFTGs are produced from structural steel plate and can be finished as weathering steel or galvanized. After being cold bent to the appropriate shape, shear studs are welded …

A Durability Evaluation Of Class B Concrete Bridge Substructures Under West Virginia Freeze–Thaw Conditions, Nathaniel Wayne Dunbar

Graduate Theses, Dissertations, and Problem Reports (ETD)

This study evaluates whether the West Virginia Division of Highways (WVDOH) Class B concrete specification for bridge substructures remains adequate under modern durability and design-life expectations. The current specification, which permits a minimum compressive strength of 3,000 psi, reflects practices established when shorter service lives were generally assumed. Modern AASHTO LRFD provisions are based on a 75-year design life, raising concern that this lower-strength concrete may not provide sufficient durability under West Virginia’s climatic conditions.

To address this issue, bridge inspection data, regional climate mapping, and durability modeling were used to assess the condition and performance of concrete substructures across …

Performance Evaluation Of Composite Utility Structures Under Wildfires And Mitigation Methods, Siddhant Sitoula

Graduate Theses, Dissertations, and Problem Reports (ETD)

The Fiber Reinforced Polymer (FRP) composite utility poles and crossarms have been getting wider attention from the utility industries because of their advantages over the traditional wooden, concrete, and steel poles. Wood is vulnerable to fire, rot, and animal damage. Concrete poles are heavier, increasing both transportation and installation costs of the poles, in addition to limited-service life (40-50 years). Similarly, steel poles have durability and safety concerns because of their inherent corrosive nature and conductivity. These disadvantages are significantly reduced by the use of FRP composites in utility structures because of FRP’s strength, specific gravity, flexibility, non-conductivity and durability …

Evaluation Of 50’ Frp Truss Bridges With Timber Decks, Maxwell Browning Carey

Graduate Theses, Dissertations, and Problem Reports (ETD)

Fiber-reinforced polymer (FRP) composites have become mainstream structural materials and are being utilized in many different structural applications because of their outstanding thermos-mechanical properties and other characteristics. These characteristics include exceptional corrosion resistance, energy absorption, durability, high strength-to-weight, stiffness-to-weight ratios, and others. Also, FRP composites are cost effective especially when accounting for the service life of such a material.

In this study, testing and analysis were performed at both the component as well as a structural system levels. Herein, two FRP truss bridges of different widths with 50 ft. spans underwent extensive testing and analysis in accordance with AASHTO specifications. …

Advancing Gfrp Column Design: Strength, Effective Lengths, And Failure Modes, Jack Alan Wykle

Graduate Theses, Dissertations, and Problem Reports (ETD)

Glass fiber reinforced polymer (GFRP) composites have become an increasingly popular choice in construction industry due to their higher strength-to-weight ratio, ease of manufacture including lower Embodied Carbon Factor, and better durability in harsh environmental conditions than conventional structural construction materials. Currently, GFRP composite column design lacks well-established design standards due to the material's unique properties such as lower bending and shear stiffness than steel, differing compressive and tensile moduli, which leads to complexities in computing buckling capacities under local effects such as flange or web buckling and even torsional buckling under off-centered compression loading. Therefore, GFRP columns will behave …

Static Response Of Frp Structural Systems – Piles, Platforms, And Poles, Manish Adhikari

Graduate Theses, Dissertations, and Problem Reports (ETD)

This study addresses the static response of three Fiber Reinforced Polymer (FRP) structural systems (piles, platforms, and poles) under static loads. This research aims to improve safety and sustainability in modern infrastructure by bridging the knowledge gap currently that exists between the experimental behavior and theoretical predictions.

FRP round piles (18-inch in diameter) were tested under axial compression, shear, four-point bending and fatigue. Both the load-deflection and stress-strain responses were analyzed. Coupon tests were conducted and related to the outcomes of full-scale test data. Two major differences were observed in the response of the bending test specimens with modulus of …

Development And Validation Of Improved Live Load Distribution Factors For Moment In Press-Brake-Formed Steel Tub Girder Bridges, Brook Teklu Woldegabriel

Graduate Theses, Dissertations, and Problem Reports (ETD)

Press-brake-formed tub girders (PBFTGs) offer innovative solutions for short-span steel bridge applications, possessing efficiency, versatility, and sustainability. These girders are galvanized shallow trapezoidal boxes fabricated from cold-bent structural steel plates. Depending on the design requirements, a concrete deck or other deck options, such as a steel sandwich plate system, can be placed on the girders. The Short Span Steel Bridge Alliance (SSSBA) extensively researched the steel PBFTG bridge system. As a testament to its potential, the AASHTO Innovation Initiative (AII) recognized it as a 2021 Focus Technology. AII has shown commitment to promoting the adoption of PBFTG among its member …

Frp Pedestrian Bridges, Joseph Ryan Virga

Graduate Theses, Dissertations, and Problem Reports (ETD)

Advanced fiber-reinforced polymer (FRP) composites are being used as mainstream structural materials to build complex infrastructure systems. Such application of FRP composites can be attributed to their high strength-to-weight and stiffness-to-weight ratios, corrosion resistance, higher energy absorption, durability, and competitive life-cycle costs. FRP composites are increasingly being considered as suitable alternative structural materials to traditional construction materials such as timber, concrete, and steel.

In this work, detailed experimental investigation has been carried out on different types of glass FRP composite pedestrian bridges with FRP and/or timber deck. Four full-scale FRP pedestrian bridges, including 70`×8.5’ and 70’×10’ single-span bridges, a 16’×8’ …

Evaluations Of Frp Composite Coupons Under Impact And Puncture, Lekhnath Bhandari

Graduate Theses, Dissertations, and Problem Reports (ETD)

Evaluations of FRP Composite Coupons Under Impact and Puncture

Lekhnath Bhandari

Railroad tank cars are the main mode of transportation for carrying flammable liquids and other hazardous materials, in any mode of ground transportation system. These tank cars, if punctured during derailments may explode releasing large amounts of hazardous materials and posing serious threats to human life and leading to economic losses. To minimize such catastrophes, in 2015, United States Department of Transportation (USDOT) proposed to improve the thermal and puncture performances of these tank cars and introduced two new design specifications: DOT-117 and DOT-117R. Tank cars with 9/16 inches …

Strengthening Of Damaged Structural Members With External Frp, Krishna Tulasi Gadde

Graduate Theses, Dissertations, and Problem Reports (ETD)

Fiber reinforced polymer (FRP) composites are excellent alternatives to traditional materials for civil infrastructure. Several researchers have worked on the application of FRP composites for construction, repair, and rehabilitation of structures. This research aims at evaluating the use of carbon, glass, basalt, and hybrid FRPs with epoxy and polyurethane resin systems for rehabilitation of damaged structural components. Following evaluations were carried out in this research: (i) tension testing of FRP coupons, (ii) compression testing of concrete cylinders with and without damaged sections/FRP reinforcements, (iii) flexural testing of external-FRP reinforced RC beams with and without damages, (iv) pull-off tests on FRP …

Review Of Innovative Rehabilitation Techniques For Reinforced Concrete Buildings, Demetrius Karoubas

Graduate Theses, Dissertations, and Problem Reports (ETD)

Building rehabilitation encompasses the act of repairing damaged structural elements, as well as the upgrading of older buildings to bring them up to modern standards. In recent years, due to the extreme economic and environmental cost of new construction, building rehabilitation is gaining ground as the most viable solution to the problem posed by damaged or substandard buildings. With the constant development of new materials with favorable properties and the improvement of our understanding of earthquakes, new rehabilitation techniques are being developed, improving on the efficiency and effectiveness of older ones. Reinforced Concrete (RC) buildings are a type of building …

Experimental And Design Evaluation Of Multi-Bolted Gfrp Joints, Amir Hossein Houshmandyar

Graduate Theses, Dissertations, and Problem Reports (ETD)

For infrastructure system implementation, high strength/stiffness to self-weight ratio, corrosion resistance and ease of fabrication are just a few of the many advantages of pultruded fiber reinforced polymer (PFRP) composites over traditional construction materials. However, challenges of engineered FRP materials are addressed via continuous updating of design codes. For example, the anisotropic nature of FRP composite materials includes different mechanical properties in different directions (pull or longitudinal direction vs. transverse to pull direction) of a structural member, resulting in design complexities over isotropic materials. Typically, infrastructure systems are built by bolting FRP structural members because of certain advantages of bolted …

Finite Element Method Calculation Of A Prestressed Self Consolidating Concrete Beam, Vladyslav Machulsky

Graduate Theses, Dissertations, and Problem Reports (ETD)

In this study, a prestressed concrete box beam produced for the Stalnaker Run Bridge (SRB) replacement project using self-consolidating concrete (SCC) was simulated using finite element method (FEM) numerical technique. ANSYS, a commercial FEM software, was used to build the prestressed SCC box beam model. The FEM model was developed to understand the behavior of concrete and steel under prestressing loads, long-term effects, and superimposed loads. The SOLID65 and REINF264 element types were chosen to simulate the behavior of concrete and steel materials. Experimentally measured mechanical properties of concrete from the SRB project were used in the analysis allowing for …

Expanding The Applicability Of Press-Brake-Formed Tub Girders Through The Extension Of The Maximum Span Length And The Evaluation Of Pier Continuity, Robert M. Tennant

Graduate Theses, Dissertations, and Problem Reports (ETD)

The Short Span Steel Bridge Alliance (SSSBA) is a group of bridge and buried soil steel structure industry leaders who provide educational information on the design and construction of short-span steel bridges in installations up to 140 feet in length. Within the SSSBA technical working group, a modular, shallow press-brake-formed tub girder (PBFTG) was developed to address the demand in the short-span steel bridge market for rapid infrastructure replacement solutions. PBFTGs consist of modular, shallow, trapezoidal boxes fabricated from cold-bent structural steel plate. A concrete deck, or other deck option, may be placed on the girder, and the modular unit …

A Parametric Study Of Lateral-Torsional Buckling In Pultruded Frp Beams Using Abaqus, Robert Nathaniel Baylor

Graduate Theses, Dissertations, and Problem Reports (ETD)

Fiber Reinforced Polymer (FRP) composites continue to gain popularity in civil and mechanical infrastructure due to a high strength-to-weight ratio, corrosion-resistance, and low maintenance requirements. FRP can also fulfill niche roles requiring non-conductivity and magnetic transparency. The longitudinal forming of pultruded FRP makes it a natural choice for lightweight beams. Although FRP composites have a high strength for their weight, the elastic and shear moduli for glass FRP may only be 1/7 and 1/30 that of steel, respectively. These low stiffnesses make FRP composite beams particularly susceptible to lateral-torsional buckling (LTB). In addition, the low shear to elastic stiffness amplifies …

Nondestructive Condition Assessment Of Civil Infrastructure Using Ultrasonic Technique, Tyler Keith Ashbrook

Graduate Theses, Dissertations, and Problem Reports (ETD)

Civil Infrastructure controls the way people live by providing safe passage and shelter across the entire globe. Since safety leads the concern in infrastructure, it is essential to ensure that these structures have been adequately tested and analyzed periodically. Testing these structures can be extremely expensive when parts are required to be removed to capture the flaw, which is why nondestructive testing (NDT) continues to grow in demand since it can evaluate the structural component in-situ without causing any damage. Ultrasonic testing (UT) helps to adequately sustain and advance the safety in existing and future infrastructure across the globe. Continual …

Timber Bridge Pile Splicing With Fiber Reinforced Polymer Wraps, Drew L. Damich

Graduate Theses, Dissertations, and Problem Reports (ETD)

Timber pile repair using splicing is widely used but little research has been done to determine their strength capacity after repair using this method. Current timber pile splicing mechanisms utilize various steel or wooden components. Fiber Reinforced Polymer (FRP) wraps can be utilized as replacement to conventional materials in splicing of timber piles. This study evaluated the strength capacities of traditional splicing mechanisms in relation to FRP wrap splice mechanisms. Traditional splicing mechanisms consisted of flat steel plate, C-channel steel plate, and wooden plate splices. The FRP wrap splice consisted of unidirectional glass/epoxy composite with three layers of fabric as …

Estimation And Mitigation Of Stresses In Mass Concrete Structures Containing Ground Granulated Blast Furnaceslag And Fly Ash, Guadalupe Leon

Graduate Theses, Dissertations, and Problem Reports (ETD)

In large concrete structures, due to concrete’s low thermal conductivity, the interior temperature rise can approach the concrete’s adiabatic temperature rise. As the concrete’s surface losses heat to the environment and cools rapidly, the interior of the concrete attempts to expand while the exterior provides an internal restraint. The phenomenon causes thermal stresses at the concrete’s surface. If the thermal stresses exceed the concrete’s tensile strength, there is a high probability of cracking. The cracks usually appear during the first few days after construction while the concrete’s tensile strength is low. These early-age cracks can reduce the service life of …

On-Site Measurement Of The Water-Cementitious Ratio And Heat Of Hydration Of Delivered Concrete, Seyednavid Mardmomen

Graduate Theses, Dissertations, and Problem Reports (ETD)

In this study, AASHTO T318-15 was adopted to estimate the water content of fresh concrete mixes and then revised to have better precision. The additional step required sieving out the coarse aggregate after drying the sample in a microwave oven, and it was then used in the calculation of the absorbed water and cementitious material content. Several laboratory batches, as well as on-site water-cementitious (w/cm) ratio tests, were performed on concrete mixes containing ordinary Portland cement, ground granulated blast furnace slag, and Class F fly ash. The results of the experiments indicated that the accuracy of the revised method was …

Time-Dependent Reliability Framework For Durability Design Of Frp Composites, Rajneesh Kumar Bharil

Graduate Theses, Dissertations, and Problem Reports (ETD)

The life-cycle performance, durability, and aging characteristics of Fiber Reinforced Polymer (FRP or Structural Composites) have been of keen interest to the engineers engaged in the FRP design, construction, and manufacturing. Unlike conventional construction materials such as steel and concrete, the design guidelines to account for the aging of FRP are somewhat scattered or not available in an approved or consistent format. Loss of strength over time or aging of any structural material should be of concern to engineers as the in-service lifespan of many engineering structures is expected to exceed 100 years. Use of durability strength-reduction factors or factors …

Experimental And Field Evaluation Of Frp Pedestrian Bridge Decks, Kalrav Singh Tomer

Graduate Theses, Dissertations, and Problem Reports (ETD)

Traditional materials such as steel, timber, and concrete have continued to dominate their usage in civil infrastructure. They offer great advantages like strength and stiffness but at the same time they pose major issues in terms of durability and maintenance. Fiber reinforced polymer (FRP) exhibits outstanding properties like lightness, excellent corrosion and wear resistance along with superior thermo-mechanical properties. Glass FRPs (GFRPs) have emerged as one of the best alternatives in the field of civil infrastructure. It has been more than four decades since fiber reinforced polymer (FRP) composites have gained notable applications in civil infrastructure industry. However, FRPs have …

Monotonic Response Of Rc Exterior Beam-Column Joints Reinforced With Filler-Modules And Frp Composite Wraps/Gussets, Praveen Kumar Reddy Majjigapu

Graduate Theses, Dissertations, and Problem Reports (ETD)

A review of post-earthquake reconnaissance studies revealed that reinforced concrete (RC) structures, designed and built before the development of Uniform Building Code (UBC) seismic design guidelines in 1976, have suffered complete collapse or severe damages due to the brittle failure of exterior beam-column joints. Over the past 50 years, several studies were conducted to strengthen exterior joints of in-service structures, with limited emphasis on developing simple, economic and durable repair strategies to improve energy absorption through large inelastic joint deformations. Even less emphasis was devoted to developing repair procedures that minimize stress-concentrations at joint corners and enhancing the strength, ductility, …

Effects Of Supplementary Cementitious Materials On Early-Age Tensile Creep And Shrinkage Of Concrete, Lucas James Bucklen

Graduate Theses, Dissertations, and Problem Reports (ETD)

Determination of early-age tensile creep properties is critical for the performance of mass concrete structures at an early age. Due to the stress relaxation that tensile creep induces in concrete structures, accurate quantification of creep deformation is needed to determine the stress profile of the structure. Conventional methods of measuring tensile creep include the direct tension test where the concrete is subject to constant tensile stress. This method requires large quantities of concrete with embedded strain gauges which can only be used once. In this paper, the tensile creep parameters of concrete are found by using the restrained concrete ring …

Field Evaluation Of A Modular Press-Brake-Formed Steel Tub Girder In An Application That Includes Skew And Superelevation, Adam D. Roh

Graduate Theses, Dissertations, and Problem Reports (ETD)

The Short Span Steel Bridge Alliance (SSSBA) is a group of bridge and culvert industry leaders (including steel manufacturers, fabricators, service centers, coaters, researchers, and representatives of related associations and government organizations) who have joined together to provide educational information on the design and construction of short span steel bridges in installations up to 140’-0” in length. A technical working group from within the SSSBA developed the notion for the modular shallow press-brake-formed steel tub girder as a solution for the short span steel bridge market.

After extensive testing at West Virginia University and multiple successful field demonstrations, members of …

Bending Response Of Timber Mortise And Tenon Joints Reinforced With Filler-Modules And Frp Gussets, Andrew Robert Pacifico

Graduate Theses, Dissertations, and Problem Reports (ETD)

In 2013, the California Bay Area (CBA) passed a set of ordinances to ensure that their 10,000 plus timber soft-story buildings were prepared for seismic events, through nondestructive evaluation methods. Many property owners are searching for an affordable retrofitting system that will also meet CBA’s new laws focusing on installations by the mandated deadlines in 2020. Over the past three to four decades, Fiber Reinforced Polymer (FRP) composites have found their way into the civil infrastructure sector for rehabilitation. The objective of this study is to evaluate the bending behavior retrofitted mortise and tenon timber joints reinforced with engineered wood …

Structural Behavior Of Steel Plate Embedded Hybrid Gfrp Shapes, Piyush R. Soti

Graduate Theses, Dissertations, and Problem Reports (ETD)

The civil infrastructure industry has been dominated by traditional materials such as steel, timber, and concrete. Although these materials offer great advantages, they have major durability issues in terms of corrosion, decaying, and cracking. Traditional material-based structures deteriorate frequently and require regular-interval repairs with huge expenditures. To resolve these maintenance and durability issues associated with traditional materials, fiber reinforced polymer (FRP) composites have gained some popularity in the past few decades because of their superior mechanical properties and durability. Carbon-FRPs (CFRPs) and glass-FRP (GFRPs) are the most commonly used FRPs in the market. However, in civil engineering applications, CFRPs are …