Engineering Commons^™

Lcc Mse Walls, Joel Smith

Theses and Dissertations

Lightweight cellular concrete (LCC) is mainly a mixture of water, cement, and foam bubbles. LCC generally has a cast density between 20-60 pcf and an air content between 49-84%. LCC is often used as a fill material because it has a low unit weight which reduces settlement. LCC is increasingly being considered as a backfill behind Mechanically Stabilized Earth (MSE) walls and embankments. Although engineers are using LCC in MSE walls or free face walls (MSE wall without the concrete panels or reinforcements), there is presently a lack of information regarding the performance and behavior of LCC to guide them. …

Compressive And Flexural Tensile Strength Impacts Of Aluminum Shavings In Concrete, Ian Smith

Construction Management

Concrete is one of the most utilized construction materials around the world, but new and cutting-edge methods are constantly pushing the envelope for concrete’s applications and feasibility as a construction material. Unfortunately, concrete has a general lack of resistance to bending and stretching. Studies have shown several successful attempts to enhance the mechanical properties of concrete through implementation of various admixtures and methods. Steel is widely considered the primary material capable of reinforcing concrete. This paper evaluates concrete’s change in strength of flexural tension and compression as a result of implementing aluminum as a reinforcing agent. To determine the full …

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 …

Experimental Investigation Of Water Quality Impact On The Compressive Strength Of Concrete, Shayan Sharifzad

Civil Engineering Dissertations

Water is an indispensable component in concrete, as it enables crucial chemical reactions. Therefore, the quality of water used in concrete plays a vital role in its performance. Contaminated water, sewage, or high-salt water can disrupt the cement's setting process and overall performance. As a result, it is crucial to prioritize the use of drinking water or water of equivalent quality in concrete production. While the ideal water-to-cement ratio for concrete is typically around 0.20, practical considerations often require a higher water content ranging from 0.30 to 0.70. This increased water consumption is necessary to ensure workability and achieve optimal …

Slab Extension At Woods Humane Society, Corey K. Smith

Construction Management

Woods Humane Society is an animal shelter that provides pet rehabilitation and adoption services to San Luis Obispo and surrounding areas. The Woods’ facility contains a number of kennels for dogs as well as numerous outdoor, fenced-in, concrete exercise yards. These yards give dogs the opportunity to play outside a few times a day allowing them to get vital exercise. One of these yards on the south side of the property had an exterior fence that was offset from an existing slab on the interior of the fence by one foot. This was an issue for the shelter as dogs …

Optimal Concrete Mix Design And Finish For Skateboarding Performance, Lohgan Christoper Spencer

Construction Management

While concrete has been used in construction for hundreds of years, the introduction of concrete to skateboarding is a relatively new development. Concrete and concrete finishes are very well studied in the context of buildings and building design. Shotcrete is also very well understood as it has been in use for over 100 years. Because it is a relatively new sector of the industry, concrete skatepark construction is an area that has plenty of room for research and development. This research paper will describe the finish methods and mix designs used for concrete skatepark construction by leading skatepark construction companies …

City Farm Slo ‘Garden For All’ – Shade Structure, Reed Aitken

Construction Management

Local non-profit, City Farm SLO, recently presented an opportunity for four Cal Poly Construction Management students to complete senior projects to construct their vision of a “Garden for All.” This paper will focus on the design, preconstruction, and construction processes necessary to complete the shade structure. The project will provide much needed shade to an outdoor classroom area where City Farm SLO hosts farm based education programs all year round. The completion of this senior project required thorough design, estimating, coordination, and construction efforts, while keeping safety and sustainable building practices at the forefront of every decision. This was particularly …

Effects Of Admixes On The Compressive Strength Of Permeable Concrete, James T. Lyon

Construction Management

Compression tests were performed on three samples of permeable concrete to evaluate the effects of admixes on a conventional permeable concrete. The first mix served as the control, representing a standard permeable concrete sample. The second mix replicated the control but added a small amount of fiberglass, accounting for 0.5% of the cement's weight. The third mix again mirrored the control and incorporated the manufacturer's recommended amount of a water reducing admix known as "Reducer 555". The objective of testing the two new mixes against the control mix was to evaluate the potential increase in ultimate compressive strength. Four 6” …

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 …

Improving Bridge Concrete Overlay Performance, Gregory Vieira

Theses and Dissertations

Low slump concrete overlays have been widely utilized in the midwestern United States, including Wisconsin, to mitigate bridge deck deterioration and extend service life. However, concerns regarding their performance have necessitated investigations into optimal mix designs, placement procedures, and curing practices. This study focuses on assessing the cracking potential of seven overlay mixtures, including: Current Wisconsin Grade E concrete with Type I and IL cement, latex modified concrete, fly-ash modified Grade E concrete, Grade E with reduced cement content, and fiber reinforced concrete. The various concrete mixtures were tested for compressive strength, slump, and air content. Seven 8ft x 8ft …

On The Feasibility Of Embedding Fe-Sma Short-Fibers In Ultra-High-Performance Concrete For Self Prestressing, Gavin Briggs

Graduate Theses and Dissertations

Prestressing concrete is common practice in the construction industry. Current prestressing methods are often used for large, straight members and come with geometric limitations for curved or thin-walled members. Shape memory alloy short fibers embedded within concrete mixes may allow for the prestressing of geometries not possible with traditional methods. This study reviews past research on prestressing concrete with shape memory alloys, evaluates the achievable recovery stress within an Fe-SMA (when deformed at room temperature), and examines the mechanical behavior of Ductal dark grey UHPC when heated to 250 °C. The flexural behavior, compressive strength, and fiber-to-concrete bond strength of …

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 …

United Methodist Children Center Drain Project, Andy Abdelnour

Construction Management

The United Methodist Children Center in San Luis Obispo is a preschool for young children in our community. Some of these students are the children of Cal Poly faculty and staff. The previous drain was not draining water properly and was uneven with bumps and dips that became a hazard for the children. Children would trip, fall, and hurt themselves on the drain. A team of two Cal Poly Construction Management students Ethan Lin and Andy Abdelnour worked together to estimate, design, coordinate, demolish, and construct a new section of the drain that would be safe for the students. The …

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 …

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 …