Engineering Commons^™

Load Determination, Strengthening, And Behavior Study Of Prestressed Concrete Channel Bridge Girders In South Carolina, Elhussien Khaled Elbatanouny

Theses and Dissertations

The South Carolina Department of Transportation (SCDOT) is currently engaged in a multi-year effort to assess the structural integrity of its inventory of over 9,000 bridges. This assessment process is expected to result in an increase in the number of bridges that require load postings, repairs, or replacements across South Carolina. This could potentially lead to adverse economic repercussions due to restricted truck routes, bridge closures, repair work, and the need for bridge replacements. To alleviate the escalating costs associated with these challenges, it is imperative to explore methods aimed at reducing the need for load postings and bridge closures …

Optimization Of The Self-Healing Efficiency Of Bacterial Concrete Using Impregnation Of Three Different Precursors Into Lightweight Aggregate, Omar Omar

LSU Master's Theses

Concrete is the most broadly used construction material; thus, developing sustainable concrete is essential to decrease greenhouse gas (GHG) emissions from concrete production. Implementation of self-healing concrete technologies is a promising approach to enhance the durability and sustainability of the transportation infrastructure. Among these technologies, bacterial concrete has the potential to seal microcracks through microbial induced calcite precipitation (MICP). Bacterial protection is essential to ensure the viability of this technology due to concrete’s harsh environment. Additionally, the success of this technology depends on the presence of an adequate mineral precursor compound and nutrient for the bacteria. As such, the main …

Development Of Self-Stressing Ultra High-Performance Concrete Using Expansive Chemical Admixtures, Lane Edwards

Graduate Theses and Dissertations

This study investigated the effects of expansive chemical admixtures on ultra-high performance concrete (UHPC) and self-stressing mechanisms. A literature review was performed to determine different types of expansive admixtures for feasibility of the self-prestressing concept. Ultimately it was decided that type-k cement, made by combining Komponent admixture with conventional UHPC, was the most suitable option due to its effects on wet and hardened concrete properties. Mix designs with varying amounts of Komponent were developed to test the effects the admixture had on various properties. Tested properties included, workability, compressive strength, expansion, short-term shrinkage, long-term shrinkage, and developed prestress. The development …

The Influence Of The Addition Of Recycled Asphalt Shingles On The Compressive Strength Of Concrete, William E. Webb

Honors College Theses

The purpose of this study is to explore the effect of recycled asphalt shingles (RAS) as an additive on the compressive strength of concrete. This was accomplished by designing a concrete mix and creating 4” by 8” cylindrical test specimens containing 0, 5, 10, and 15 percent RAS by weight. The compressive strength was measured through axial loading until failure utilizing a compression testing apparatus. With these results, a relationship between the content of RAS and compressive strength was able to be developed, giving insight as to how RAS could be used in concrete mixes in the future. This study …

Adiabatic Temperature Rise And Durability Performance Of Slag Blended Concrete, Hai Zhu

USF Tampa Graduate Theses and Dissertations

Performance and durability of slag blended concrete was investigated in this study focusing on slag and cement characteristics. Seven slags with variable Al2O3 content, Al2O3/MgO ratio and fineness were selected for investigation. The eight selected cements included ASTM Type I, Type I(HA), Type II(MH), Type II(MH)(HA), and Type IL(10 and 14). Cementitious materials studied here were subjected to a battery of tests including physical, chemical and mineralogical characterization. Performance and durability testing included heat of hydration measurements, sulfate optimization, external sulfate resistance, adiabatic temperature rise and chloride ingress.

Adiabatic temperature rise was assessed on 60% slag blended concrete, using Type …

Feasibility Of Applying Motion Magnification In Subsurface Defect Detection For Concrete And Fiber-Reinforced Polymer Specimens, Nagavardhani Malineni

Graduate Theses, Dissertations, and Problem Reports

Irrespective of size and complexity, every civil infrastructure needs certain scrutiny regarding its structural health to ensure its serviceability during its lifetime. In olden times such scrutiny was done with the aid of destructive testing methods using sensors that required cumbersome and expensive installations and led to the destruction of at least part of the tested specimen. However, in recent times, many non-destructive methods, such as acoustic emission testing, electromagnetic testing, and laser testing methods have emerged, leaving the specified tested specimen undisturbed. With the advancement in sensor technology like motion magnification and with the help of access to high-speed …

Nondestructive Evaluation Of Structural Defects In Concrete Slabs, Ehsanul Kabir

Electronic Theses and Dissertations

Nondestructive testing (NDT) is a reliable method for determining the structural integrity of new and old construction and understanding the condition of structural defects. It is widely acknowledged that the interpretation of nondestructive evaluation (NDE) has a significant impact on the reliability and consistency of this technology. However, NDT data acquisition remains subjective and heavily dependent on the operator’s knowledge and expertise. As a result, there are still issues to be resolved regarding the imaging and diagnostic procedures for NDT-based concrete inspection. NDT methods such as ground penetrating radar (GPR), and impact-echo (IE), have been extensively used to inspect concrete …