Engineering Commons^™

Evaluating The Bond Behavior Between Frp And Grooved Concrete Specimens Using Single Shear Pull Out Test, John Omboko

Master's Theses (2009 -)

Surface preparation affects the bond behavior between Fiber Reinforcing Polymer (FRP) composite material and concrete. In this research, a special type of surface preparation known as grooving, which involves cutting transverse grooves, is conducted on concrete blocks (specimens) that are categorized as either Unfilled (U) or Filled (F). This idea is to ascertain how the grooves affect the strength of FRP-bonded-concrete specimen. These two categories are then benchmarked to control (C) specimens which do not have grooves on them. Category U specimens only have the epoxy applied on the concrete surface while category F specimens have epoxy applied on both …

Electrochemical Methods To Characterize Drilled Shaft Deficiencies, Sarah Jo Mobley

USF Tampa Graduate Theses and Dissertations

In recent years drilled shafts have become the preferred foundation method for marine bridges. Typically, the drilled shaft is selected over traditional driven piles due to soil strata encountered, construction economy, increased lateral stiffness requirements, and/or vibration control considerations. The most critical component in drilled shaft construction is borehole stabilization. Wall sloughing or groundwater inclusion can have devastating effects on the strength of the finished shaft however recent research has shown that the materials, more specifically the slurry, used to accomplish stabilization may be having a negative impact on the durability of the finished product. This thesis investigates the durability …

Preparations Of Mno2 Reference Electrodes For Corrosion Monitoring Of Reinforced Concrete, Li Yang, Bing Xu, Hai Wang, Ze-Hua Dong

Journal of Electrochemistry

In this work, the solid reference electrode was assemblied by using the electrochemically synthesized manganese dioxide (MnO₂) (EMD) powder, gel electrolyte and thin mortar layer for the durability evaluation of concrete. The EMD reference electrode exhibited higher potential stability (< 10 mV drift) than the chemically synthesied MnO₂ (CMD) based on half year potential tests in the saturated Ca(OH)₂ solution and hardened mortar. In addition, the EMD electrode was almost insensitive to the presences of chloride ion and corrosion inhibitor. Electrochemical impedance and polarization curves indicate that the EMD electrode had lower charge transfer resistance,higher exchange current density and lower temperature coefficient than the …

Ductile Corrosion-Free Gfrp-Stainless Steel Reinforced Concrete Elements, Maged A. Youssef, Mohamed E. Meshaly, Ahmed Elansary

Civil and Environmental Engineering Publications

Corrosion of steel rebars is known to cause deterioration of concrete structures that can lead to catastrophic failures. To mitigate this problem, steel rebars can be replaced with Glass Fiber-Reinforced Polymer (GFRP) rebars. However, the lack of ductility of GFRP-reinforced elements has prevented their use in many structural applications, especially in seismic areas. Stainless Steel (SS) rebars are corrosion resistant and have adequate energy absorption and ductility. However, they are much more expensive than steel rebars. This paper proposes the combined use of SS and GFRP rebars to achieve ductile and corrosion-free elements. The first challenge for such a proposal …

Compressive Strength Relative To Sustainable Materials In Concrete, Brad Harvey

Williams Honors College, Honors Research Projects

The objective of this study is to determine how integrating abundant waste materials into concrete affects its compressive strength. This research will be used to benefit the construction industry by replacing a portion of a conventional concrete mix (cement, stone, sand, and water) with more sustainable materials. In order to create a more sustainable concrete mixture, the following mix design and methodology was followed.

The initial step was to create an updatable MS Excel spreadsheet to aid in the mix development (the spreadsheet is shown in Appendix A). These sheets allowed for easy transitions from one mix to another by …

Chemical Modification Of Crumb Rubber To Increase Its Bonding With Concrete, Mary T. Mccannon, Kendall J. Sweitzer

Williams Honors College, Honors Research Projects

The hydrophilicity of crumb rubber was increased with wet chemical modification and added to concrete to increase its adhesion with concrete, consequently the compressive strength relative to that of concrete with untreated rubber. Other modification methods were tested on crumb rubber and rubber sheets to yield an increase in hydrophilicity. Certain tests were less reliable for powder testing or tedious and time consuming and concrete materials and rubber may not be homogeneous.

For wet chemical modification, several approaches were attempted. First, crumb rubber was soaked in 5% sodium hydroxide, 5% potassium permanganate and saturated sodium bisulfite, tested for hydrophilicity using …

Healing Mechanism Investigation Of Self-Healing Concrete By Microencapsulated Calcium Nitrate, Gabriel Andres Arce Amador

LSU Doctoral Dissertations

Durability of reinforced concrete structures depends highly on the integrity of the concrete which protects the structure from the environment. However, concrete is a brittle material and as such it is prone to cracking which allows for detrimental agents to penetrate the structure and produce early deterioration. Embedding microcapsules with chemical healing agents in concrete materials for self-healing applications as well as implementing SMAs as reinforcement of concrete structures for self-closing of cracks are both state-of-the-art techniques with enormous potential for enhancement of concrete infrastructure durability. In this work, both techniques are combined as an alternative for superior self-healing of …

Integration Of Shape-Memory Alloys And Self-Healing Microcapsules To Enhance Concrete Durability, Luis Adolfo Bonilla

LSU Doctoral Dissertations

Self-healing is a term that has not been used for building material until a few decades ago. The concept of developing a material that mimics what living organisms do, such as identify and repair damage, rather than interesting, constitutes a necessity in today’s deteriorated infrastructure. Concrete is one of the main building blocks that support our society’s roads, buildings, and dams. Increasing the service life of such structures will have an important socio-economic benefit in our society. Self-healing methods in concrete have been studied in order to minimize human intervention in maintenance procedures. Previous research in this area has provided …

Identifying Damage, Predicting Expansion, And Determining The Effectiveness Of Sealers On Concrete Affected By Alkali-Silica Reaction And Freeze-Thaw, Matthew Caleb Waidner

Graduate Theses and Dissertations

Premature cracking of the barrier wall and pavement on I-49 south of Fayetteville, Arkansas due to a combination of Alkali-Silica Reaction (ASR) and freeze-thaw has led to ASR and freeze-thaw research at the University of Arkansas. Potential for further expansion (PFET), Damage Rating Index (DRI), and mitigation of freeze-thaw and ASR with sealers testing and results are contained herein. PFET results indicated that the pavement will not continue to expand from ASR. With other interstate pavements deteriorating prematurely throughout Arkansas, DRI has shown that most are damaged not only by ASR but by freeze-thaw too. Recommendations for freeze-thaw’s inclusion into …

Continuous Long-Term Health Monitoring Using Ultrasonic Wave Propagation, Ece Erdogmus

Nebraska Department of Transportation: Research Reports

No abstract provided.

Feasibility Study Of Using Recyclable Polyethylene (Pet) Materials As Coarse Aggregate For Concrete Mixtures, Philip M. Angelo

Construction Management

The feasibility of using recyclable household plastics, specifically those made of polyethylene, commonly used in water and soda bottles, as a replacement for concrete coarse aggregate, was assessed. A method was developed for cutting polyethylene materials into fibrous strips. These strips were then used as a replacement for the rock coarse aggregate in batches of concrete. Standard 6” x 12” test cylinders were made using the concrete mixture and subject to destructive compressive testing in order to yield the compressive strength of the concrete mix 7, 14, 21, and 28 days after pouring. Three mixtures were tested, one control with …

Reflectivity Of Light Emitting Diodes (Led) And Incandescent Lights On Concrete And Asphalt Pavements., Jeremy Elliott Rice

Electronic Theses and Dissertations

The purpose of this study is to investigate the reflectivity of light on concrete and asphalt pavement systems. In 1983, the Illuminating Engineering Society (IES) published the first recommended practice (RP-8) for the design of roadway and parking lot lighting. This design method implemented empirically tested factors which were defined as the “reduced luminance coefficients” or the R-Tables. The R-Tables are essential for proper design of light pole installation dimensions, required power, and the distribution of light. The originally tested pavements are not necessarily representative of modern pavement materials used today. Moreover, recent Light Emitting Diodes (LED) are a relatively …

Performance Of Continuous Concrete Slabs Reinforced With Hybrid Steel-Basalt Bars, Mohammad Sohayeb Akiel

Theses

Continuous steel-reinforced concrete structures are vulnerable to corrosion

Damage when exposed to harsh environment. Although replacing conventional steel entirely with basalt fiber-reinforced polymer (BFRP) bars can eliminate corrosion problems, the lower modulus of elasticity of BFRP would reduce serviceability of the structure. The use of hybrid steel-BFRP bars rather than BFRP bars only has a potential to improve the serviceability of continuous concrete

Structures without reducing the deformation capacity. Through experimental testing and numerical simulation, this work aims to examine the structural behavior of two-span concrete specimens internally reinforced with BFRP or hybrid steel-BFRP bars.

A total of 12 two-span …

Prediction Of Punching Shear Capacity Of Two-Ways Frp Reinforced Concrete Slabs, Ilker Fatih Kara, Besian Sinani

UBT International Conference

An innovative solution to the corrosion problem is the use of fiber-reinforced polymer (FRP) as an alternative reinforcing material in concrete structures. In addition to the non corrodible nature of FRP materials, they also have a high strength-to-weight ratio that makes them attractive as reinforcement for concrete structures. Extensive research programs have been carried out to investigate the flexural behavior of concrete members reinforced with FRP reinforcement. On the other hand, the shear behavior of concrete members, especially punching shear of two-way slabs, reinforced with FRP bars has not yet been fully explored. The existing provisions for punching of slabs …

Development Of A Transition Between An Energy-Absorbing Concrete Barrier And A Rigid Concrete Butress, Tyler L. Schmidt, Ronald K. Faller, Jennifer D. Schmidt, John D. Reid, Robert W. Bielenberg, Scott Rosenbaugh

Nebraska Department of Transportation: Research Reports

From 2010 to 2015, MwRSF researchers developed the RESTORE barrier, which is a restorable MASH TL-4 median barrier with a steel and concrete rail supported by elastomer posts and steel skids. The research effort reported herein describes the initial development of a transition from the RESTORE barrier to a rigid TL-4 concrete buttress.

The previously-developed RESTORE barrier LS-DYNA model was validated against three full-scale vehicle crash tests. Several design concepts were generated through a series of brainstorming efforts. The primary transition concept consisted of a pin and loop connection between the RESTORE barrier and rigid concrete buttress, which was designed …

Chloride-Binding Isotherms In Concrete Submitted To Non-Steady-State Diffusion-Migration Model, Wen-Hu Tsao, Ming-Te Liang, Ta-Peng Chang

Journal of Marine Science and Technology–Taiwan

We propose a mathematical non-steady-state, time/depth dependent diffusion-migration model based on the modified Fick’s second law of diffusion. It considers the effects of different chloride binding mechanisms for the transport process of chloride ions diffused in a porous concrete on the variation of its chloride profile. Four different chloride-binding isotherms, i.e., no binding, linear binding, Langmuir binding and Freundlich binding, together with the time/depth dependent chloride diffusivities are investigated. Results of this study show that the variations of amounts of available free chloride ions in the solution of saturated concrete resulting from different chloride-binding isotherms have significant effects on the …

Effect Of Severe Corrosion On Lateral Strength Of Square Rc Bridge Columns, Sara Sotoud

Dissertations - ALL

Corrosion of reinforcing steel bars is the primary durability problem that causes degradation of reinforced concrete structures located in aggressive environments. Severe corrosion of steel bars decreases the lateral load-carrying capacity of reinforced concrete members, causes loss in the mechanical properties of reinforcement and cross-sectional area of steel bars and concrete cover, bond deterioration, reduces anchorage of steel bars, and decreases the confinement by transverse reinforcement. Consequently, corrosion results in drop in the lateral strength of columns. Therefore, studying response of corroded reinforced concrete columns subjected to lateral loads is necessary.

According to the Federal Highway Administration (FHWA) report in …

Standardized Testing Of Non-Standard Photovoltaic Pavement Surfaces, John H. Nussbaum, Robert A. Lake, Ronald A. Coutu Jr.

Electrical and Computer Engineering Faculty Research and Publications

Emerging photovoltaic products have expanded the applications for the technologies into markets previously unconsidered for what was thought to be a delicate electronic product. One company leading this effort, Solar Roadways, Incorporated, is producing pavement replacing photovoltaic systems and proposing their use in everything from sidewalks to runways. Current pavement testing methods cannot be applied to these non-homogenous structures to identify if they can support the required loads. However, the standards called out specifically for pavements may be able to be translated to these products and their non-homogenous structures and non-standard materials to identify if they are able to perform …

Alkali Silica Reaction In Concrete Made From Arkansas Region, Adithya Reddy Mallu

Theses and Dissertations

Alkali-Silica Reaction is an unwanted reaction which occurs over time between cement paste and silica. This in turn alters the expansion of the aggregate and often in an unpredictable way, which will result in loss of strength of concrete and complete failure. This research studies the effects of using locally available coarse and fine aggregates available in Arkansas. This research will provide the necessary information in selecting the type of aggregate that is to be used in constructions and a viable comparison between different aggregates available in Arkansas have been made. Different materials used for preparation of concrete samples have …

Use Of Recycled Crushed Concrete (Rcc) Fines For Potential Soil Stabilization, Lindeman Mark, Varilek Brandon, Lieska Halsey, Rick Gloe, Maria Olomi

Nebraska Department of Transportation: Research Reports

This study evaluated the use of Recycled Crushed Concrete (RCC) Fines for potential soil stabilization. Soil stabilization is the enhancement of subgrade stability to improve the constructability of successive pavement layers. Use of RCC fines may not only provide less costly alternatives for subgrade stabilization, but their use may also alleviate landfill disposal challenges.

Edge Detection Of Concrete Mesostructure Based On Dis Operator, Bin Feng, Zicheng Xu, Jin Xia, Shijie Jin, Weiliang Jin

International Conference on Durability of Concrete Structures

Aggregate edge detection is the basis of creating concrete mesoscale model, which is applied to analyze concrete mesoscale characteristics. A concrete digital image edge detection method using DIS operator is presented in this paper. Mean filter, multi-scale filter, and Gaussian filter are compared on the effect of concrete image noise reduction. Based on the result, Gaussian filter is the most optimum method to reduce image noise and remain aggregate edge distinct. Sobel operator, Laplacian operator, and DIS operator are applied respectively to detect the aggregate edge on Gaussian filter processed images. Based on the experiment, DIS operator outperforms other two …

Aggregate Shape Effect On Multicomponent Ionic Electromigration In Concrete, Qing-Feng Liu, Long-Yuan Li, Jian Yang

International Conference on Durability of Concrete Structures

This paper presents a numerical study on the mechanism of chloride migration in concrete. Unlike most of existing work, this study utilises multicomponent ionic transport models to reflect the influence of ionic interactions by coupling both mass conservation and Poisson’s equations. A series of 2-D, 3-phase models with different shapes and volume fractions of aggregates are developed to simulate the chloride migration test. Through a comparatively overall numerical exploration that considers external voltage, ionic interactions, heterogeneous nature, ITZ, and ionic binding, some important features about multispecies coupling and aggregate shape effect, which have not been properly reported from existing concrete …

Seismic Design Of A Prestressed Concrete Bridge, Alperen Ozel

LSU New Orleans Theses and Dissertations

Latest advancements in software have become an indispensable tool in structural analysis. The main goal of this thesis is to examine dynamic responses of bridges in seismic activity with the help of such tool as CSi Bridge. Therefore, throughout this study, a prestressed concrete bridge model will be thoroughly designed. In the first section, the required materials and structural components will be introduced. The following section will cover calculations required for modeling. The actual modeling of the structure will be carried out in Section 3. In Section 4, the set of required analysis for seismic design such as modal, pushover …

A Concrete Water Pasteurization Device For Third World Countries, Andrea R. Murchie

Senior Honors Projects, 2010-2019

In the rural areas of South Africa, as well as many other developing countries, people cook food and sterilize their water by heating over open fires. Many times the fires are inside of homes, which more often than not are very small. Children will often be the ones to tend to the fire, out of necessity while parents and other family members are tending to other work and needs.

The purpose of my Senior Honors Project was to design a concrete vessel that can hold water and heat the water to pasteurization (149°F) when exposed to sunlight for an extended …

Quantification And Characterization Of Fracture Resistance In Asphalt Concrete Based On R-Curve Method, Shu Yang

Graduate Theses and Dissertations

The application of fracture energy is widely applied in the evaluation of cracking in the laboratory for asphalt concrete. However, this single number does not provide information on the characterization of the initiation and propagation of cracks. The Resistance Curve method, or R-Curve, is widely applied in characterizing various materials including, but not limited to, metal, polymer, rock, and composite. This research R-Curve method introduces asphalt concrete through a stepwise approach. First, in chapter one, there is a literature review of the history of fracture mechanics, fracture research in asphalt concrete, and an examination of the role of R-Curve application …

Impact Of Extreme Summer Temperatures On Bridge Structures, Ryan Hagedorn

Graduate Theses and Dissertations

Climate change and its effect on weather in the United States is a well-documented phenomenon. In particular, extreme heat waves have become more intense, more frequent, and longer lasting, especially in the southern United States. As with much of America’s transportation infrastructure, prestressed concrete bridge girders experience the effects of these heat waves. Uneven heating of optimized bridge girder sections results in large non-linear temperature gradients. In this study, temperature was monitored in three different AASHTO I-girders to determine the vertical and transverse temperature gradients in a pre-deck placement condition. It was determined that the current design standard, which uses …

Potential Application Of Ultra-High Performance Fiber-Reinforced Concrete With Wet-Mix Shotcrete System In Tunneling, Jean Gamarra

Civil Engineering Theses - Archive

In the tunneling industry, shotcrete has been used for several decades. The use of shotcrete or wet-mix spray-on methods allows the application of this method in complex underground profiles and shapes. The need for time efficient spraying methods and constructability for lining coverage opens the door for technologies like steel and synthetic fiber reinforced shotcrete to achieve a uniform and a good quality product. An important advantage of the application of fiber reinforced concrete in shotcrete systems for tunneling is that almost no steel fixing is required. This leads to several other advantages including safer working conditions during excavation, less …

Corrosion Of Rebar Under Carbonation And Salt Environment, Wei-Chung Yeih, Jiang-Jhy Chang, Yu-Ping Huang, Ran Huang

Journal of Marine Science and Technology–Taiwan

In this study, the behavior of reinforced concrete under carbonation and in a salt environment was investigated. Three types of cements- Type I cement, Type II cement and highalumina cement (HAC) - were used to study the influence of cement on reinforced concrete behavior. To simulate chloridecontaminated concrete, 1% NaCl (by cement weight) was added to some groups of specimens. Results revealed that the carbonation released chloride ions from Friedel's salt, which increased the chloride content near the carbonation front. The carbonation rate of HAC concrete was higher than that of Type I and Type II cement concrete. The corrosion …

Carbonation Resistance Of Concrete With Mortar Coating, Wen-Hu Tsao, Ming-Te Liang, Nai-Ming Huang, Ke-Hung Liao

Journal of Marine Science and Technology–Taiwan

The principal purpose of this paper was theoretically to study the carbonation resistance of a semi-infinite medium which concrete has a mortar coating having diffusion properties different from those of the rest of the medium. The analytical solution of a semi-infinite composite medium was used to predict the time required for subsidence due to concrete with mortar coating. The inaccurate analytical solution was published in previous books. Thus, the analytical solution of a semi-infinite composite medium is re-derived in this article. The governing equations without initial and boundary conditions in the previous books are also pointed out. In order to …

Evaluation Of Penetration Depth And Protective Effectiveness Of Concrete-Penetrating Sealer Materials, Sung-Ching Chen, Ran Huang, Hui-Mi Hsu, Si-Yu Zou, Li-Wei Teng

Journal of Marine Science and Technology–Taiwan

Crystal penetrating sealer materials (PSMs) are commonly used on the surface of concrete to protect the surface from damage and thereby extend its service life. Such materials penetrate into existing pores or cracks and form crystals, which block potential paths through which unknown materials could enter and degrade the concrete. In this study, the constituent compounds of a PSM were divided into seven categories, labeled CAT I to CAT VII, and five discrete particle size fractions corresponding to sieve Nos. 30, 50, 100, 200, and 200 were considered. Energy dispersive spectrometry revealed that the constituent elements of the PSM were …