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Full-Text Articles in Engineering

Reduction In Scc Form Pressure Through In-Situ Co2 Mineralization, Sean Monkman, Soo Duck Hwang, Kamal Khayat Sep 2024

Reduction In Scc Form Pressure Through In-Situ Co2 Mineralization, Sean Monkman, Soo Duck Hwang, Kamal Khayat

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

One challenge of using self-consolidating concrete (SCC) for cast-in-place structural applications is that the rheological properties of the concrete (low yield stress and low plastic viscosity) can lead to increased lateral pressure exerted on the formwork. High structural build up and thixotropy can reduce the lateral pressure, thereby allowing for simpler formwork and faster construction. The addition of CO2 to SCC, in proportions from 0.063 % to 0.250 %, by weight of cement, was investigated as a rheology modifier. The CO2 served to increase the plastic viscosity with little impact on the dynamic yield stress up to a …

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Batch And Placement Size Effects On The Setting Time Of Bcsa Cement Concrete, Micaiah Rivers Aug 2024

Batch And Placement Size Effects On The Setting Time Of Bcsa Cement Concrete, Micaiah Rivers

Graduate Theses and Dissertations

Belitic calcium sulfoaluminate cement (BCSA) is an alternative to portland cement which offers numerous benefits due to its rapid-setting behavior and sustainability properties. BCSA cement concrete has many potential applications, particularly for structural and transportation infrastructure repair. Due to the rapid-setting properties of BCSA cement, a comprehensive understanding of the setting process is critical for efficient and effective use of this material. The primary objective of this research was to determine the effects of mixture size on the setting time and temperature behavior of BCSA cement concrete, and to investigate the relationship between initial set time and workability. Using a …

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Experimental Investigation Of The Self-Healing Potential Of Bacteria For Sustainable Concrete Structures Phase 2, Andrea Calabrese, Pitiporn Asvapathanagul, Nisarg N. Patel, Nanubala Dhruvan, Austin Adams, Michael Hernandez, Douglas S. Lopez-Cruz Jul 2024

Experimental Investigation Of The Self-Healing Potential Of Bacteria For Sustainable Concrete Structures Phase 2, Andrea Calabrese, Pitiporn Asvapathanagul, Nisarg N. Patel, Nanubala Dhruvan, Austin Adams, Michael Hernandez, Douglas S. Lopez-Cruz

Mineta Transportation Institute

Concrete is a critical component of so much of the modern construction industry. This material, well known for its versatility, robustness, longevity, and strength, is well-suited for a wide range of structural applications. Nonetheless, the widespread occurrence of cracks in concrete structures, primarily attributed to its limited tensile strength, shrinkage, and overstain, imposes a considerable economic and environmental challenge when it comes to retrofitting these fissures. This study tackles this problem by harnessing bacteria tolerant to high alkaline conditions to enable Microbially Induced Calcium Carbonate Precipitation (MICP) for the self-repair of concrete. This is achieved through an external application method, …

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A Comprehensive Study On The Impact Of Human Hair Fiber And Millet Husk Ash On Concrete Properties: Response Surface Modeling And Optimization, Naraindas Bheel, Muhammad Alamgeer Shams, Samiullah Sohu, Abdul Salam Buller, Taoufik Najeh, Fouad Ismail Ismail, Omrane Benjeddou Jun 2024

A Comprehensive Study On The Impact Of Human Hair Fiber And Millet Husk Ash On Concrete Properties: Response Surface Modeling And Optimization, Naraindas Bheel, Muhammad Alamgeer Shams, Samiullah Sohu, Abdul Salam Buller, Taoufik Najeh, Fouad Ismail Ismail, Omrane Benjeddou

Department of Civil and Environmental Engineering: Faculty Publications

Revolutionizing construction, the concrete blend seamlessly integrates human hair (HH) fibers and millet husk ash (MHA) as a sustainable alternative. By repurposing human hair for enhanced tensile strength and utilizing millet husk ash to replace sand, these materials not only reduce waste but also create a durable, eco-friendly solution. This groundbreaking methodology not only adheres to established structural criteria but also advances the concepts of the circular economy, representing a significant advancement towards environmentally sustainable and resilient building practices. The main purpose of the research is to investigate the fresh and mechanical characteristics of concrete blended with 10–40% MHA as …

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Investigating The Performance Of Bendable Concrete Against Traditional Concrete, Landon J. Poston Jun 2024

Investigating The Performance Of Bendable Concrete Against Traditional Concrete, Landon J. Poston

Construction Management

The qualitative research in this case study evaluates the importance of bendable concrete within various construction settings. The data aims to justify the interest in bendable concrete, as well as why it is not being used more in structural work. The intended stakeholders of this paper are concrete suppliers, contractors, and researchers who are looking for more imperative ways to manufacture a more sustainable form of concrete. Through a brief online meeting and a Google Form questionnaire, company participants were able to provide the knowledge and feedback desired for how bendable concrete can be incorporated more in the future of …

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Iron Filings Impact On The Compressive Strength Of Concrete, Dominic Daniel Aceves Jun 2024

Iron Filings Impact On The Compressive Strength Of Concrete, Dominic Daniel Aceves

Construction Management

In this study, compression tests were performed on three different mix designs of concrete to evaluate the effects of iron filings as an admixture to concrete. The first mix design served as the control mix, being the variable that the other two mixes will be based off. The second mix design was the same as the first mix design, but with an added 12 ounces of iron filings. The third mix design was, again, the same as the first mix design, but with an added 24 ounces of iron filings doubling that of the second mix design. The objective of …

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Son Care Foundation – Lean To Shade Structure Design And Construction, Ryan Joseph Mccann Jun 2024

Son Care Foundation – Lean To Shade Structure Design And Construction, Ryan Joseph Mccann

Construction Management

This paper discusses the design and construction of a lean-to-shade structure built for the Son Care Foundation in San Luis Obispo. The Son Care Foundation is a nonprofit organization that raises guide dogs for veterans and first responders with PTSD. This shade structure is 16 feet long and 6 feet wide, its height slopes from 9 feet in the front down to 8 feet in the back creating a roof pitch of 2:12. The sheet metal roof also has an overhang of approximately 1 foot. As requested by the client, the shade structure was designed to fit the aesthetic of …

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Effect Of Pismo Clams As Partial Fine And Coarse Aggregate Replacement On Workability And Compressive Strength Of Concrete, Alan Munoz Pille Jun 2024

Effect Of Pismo Clams As Partial Fine And Coarse Aggregate Replacement On Workability And Compressive Strength Of Concrete, Alan Munoz Pille

Construction Management

Concrete has been utilized for ages. Unfortunately, over the hundreds of years there has been little development in the applications of new aggregate materials. The world is moving towards a sustainable way of living and as a result seashells have come into the mix. Pismo Clams are a native species to San Luis Obispo County. This marine species has the possibility of becoming a partial aggregate replacement for fine and coarse aggregates in concrete. The results of prior studies indicate a possible application of seashell use in concrete. This paper evaluates the workability and compressive strength of concrete containing fine …

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Building 21 Courtyard Barbecue Pit Demolition, Will Riviere Jun 2024

Building 21 Courtyard Barbecue Pit Demolition, Will Riviere

Construction Management

This project intended to demonstrate the process of a full-scope demolition project at a manageable scale. Almost sixteen yards of concrete were to be demolished, including all reinforcing structures within the barbecue. The purpose of this project was to clear space for the impending renovation of Building 21’s courtyard and remove the unsafe barbecue from the busy pedestrian pathway. Sledgehammers were used in conjunction with electric jackhammers to perform the demolition. Rebar from demolition was separated from the concrete and recycled separately from any cementitious materials. Careful attention was given to protecting existing brick beneath the structure, the surrounding area, …

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Moment Monument, Brayden Alec Martinez, Carsten Walker Huber, Gaspar Emmanuel Solorio, Jared Thomas Schieferle Jun 2024

Moment Monument, Brayden Alec Martinez, Carsten Walker Huber, Gaspar Emmanuel Solorio, Jared Thomas Schieferle

Architectural Engineering

We designed our project, dubbed the Moment Monument, in part to live out our dream of applying engineering and design skills towards creating a lasting impression on Cal Poly’s campus, as well as to develop a visual aid for future engineering students in steel design classes. The Moment Monument is in the Experimental Structures Laboratory, which is a space in the university’s ‘Poly Canyon’ that is reserved for students to build and test different applications of architecture, structural engineering, and construction. In recent years, it has been diffi cult to receive approval to build in the canyon due to high …

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Quality Assurance And Quality Control For Reinforced Concrete Inspections, Calvin O. Walters Jr. May 2024

Quality Assurance And Quality Control For Reinforced Concrete Inspections, Calvin O. Walters Jr.

Publications and Research

Ensuring the safety and longevity of structures is paramount in concrete construction projects. Cases like the Big Dig ceiling collapse, which occurred on July 10, 2006, when a concrete ceiling panel measuring 20' x 40' and debris weighing 26 short tons (52,000 lb) fell within Boston's Fort Point Channel Tunnel, underscore this importance (Wald, M. L., 2007). Quality Assurance (QA) and Quality Control (QC) are crucial in mitigating such risks. QA ensures that materials and methods meet predetermined performance, design, and reliability standards specified in contracts and customer arrangements. On the other hand, QC is a strategic process businesses use …

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Reducing Carbon Emissions With Returned Concrete, John M. Maxwell Jr. May 2024

Reducing Carbon Emissions With Returned Concrete, John M. Maxwell Jr.

Construction Management

The concrete industry is one of the most energy-intensive sectors of construction. Specifically, the cement production aspect is the most energy intensive, and produces the most carbon emissions. Concrete, a material ubiquitous with nearly every facet of construction; certain types of structures are composed of nearly all concrete. Production of cement is one of the biggest contributors to emissions within the industry. There have been initiatives to reduce or offset emissions from this process, through things like carbon capture, and the purchase of carbon or emissions credits. The objective of this paper was to investigate a new method of carbon …

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Laboratory Evaluation Of Early-Age Concrete Comprising Type Il Cement And Natural Pozzolans, Battsagaan Ilch Apr 2024

Laboratory Evaluation Of Early-Age Concrete Comprising Type Il Cement And Natural Pozzolans, Battsagaan Ilch

Theses and Dissertations

The objective of this laboratory research was to investigate the effects of a higher water-cementitious materials ratio on selected properties of concrete mixtures comprising natural pozzolans. The scope of work included testing of six concrete mixtures, including one for each of three natural pozzolans at two water-cementitious materials ratios of 0.44 and 0.48 and one concrete mixture without pozzolan at a water-cementitious materials ratio of 0.44, which was treated as a baseline in this research. The stiffness and strength of each concrete mixture were measured at 1, 3, and 7 days using concrete specimens that were cast immediately after mixing. …

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Effect Of Concrete Mix Design Factors On Static Yield Stress Changes Due To Vibration, Ahmed Abd El Fattah, Dimitri Feys, Kyle Riding, Syed Imran Jan 2024

Effect Of Concrete Mix Design Factors On Static Yield Stress Changes Due To Vibration, Ahmed Abd El Fattah, Dimitri Feys, Kyle Riding, Syed Imran

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Digital fabrication of concrete structures has gained substantial research traction over the last decade, enabling efficient material use and adding more architectural freedom. Current research focuses on chemical and mineral admixtures, as well as manipulating the cement hydration reaction to control the yield stress evolution with time in the cement paste. Instead of providing yield stress through the concrete fluid properties, a high yield stress can be provided by interparticle friction from the use of high aggregate volumes and large nominal maximum aggregate size, with flow enhanced for material extrusion by vibration. Granular physics was applied to concrete mixture design …

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Cal Poly Craft Center Wedging Tables, Cooper Christopher Strong Jan 2024

Cal Poly Craft Center Wedging Tables, Cooper Christopher Strong

Construction Management

The Craft Center, located on Cal Poly's campus, is where students can unwind from stressful coursework and engage in activities like pottery, surfboard shaping, and stained glass. The pottery studio needed new wedging tables, which are essential for removing air from clay before shaping it. The project involved building two new 7’ x 2.5’ tables that would fit well in the space and be durable. Designed to be 33” tall, these tables are accessible to students of varying heights. They feature a concrete surface that is both durable and porous, helping to absorb some moisture during use. The previous tables …

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Determination Of Spore Viability In Concrete Across Several Factors Using Most Probable Number, Samuel Boyer Jan 2024

Determination Of Spore Viability In Concrete Across Several Factors Using Most Probable Number, Samuel Boyer

Williams Honors College, Honors Research Projects

To determine the lowest concentration of spore added to polyurethane-cement composite (PUCCO) particles that can still germinate after curing in concrete. This research project is a small addition to the larger research project being undertaken by Mirza Mohammed Rashiduzzaman for his Masters. The larger project involves the use of fungal spores added in concrete to act as a self-healing component when cracks form in the concrete structure over time. These spores are suspended in a protective oil and loaded into small, hardened sponge-like PUCCO cubes to act as growth points when water and air can reach the PUCCO in the …

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High Strain Rate Analysis Of 3d Printed Concrete As Compared To Conventionally Cast Concrete, Weston Mcleod Thomsen Jan 2024

High Strain Rate Analysis Of 3d Printed Concrete As Compared To Conventionally Cast Concrete, Weston Mcleod Thomsen

Masters Theses

"3D Printed Concrete (3DPC) is a developing method of construction that has advantages over conventional methods, including formwork reduction, complex geometry, and expedited construction. This technology has potential benefits for the military when considering the austere environments that forward operating bases are built in. This study aims to assess 3DPC applications in protective structures that protect critical assets from explosive blasts. These protective structures experience a high-strain rate response during blast loading of the structure, and the effects of this have yet to be analyzed in the literature concerning 3DPC. With the lack of prior research, the focus here will …

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Production Of Cast-In-Place Uhpc For Bridge Applications, Jiong Hu, George Morcous, Akbota Aitbayeva Dec 2023

Production Of Cast-In-Place Uhpc For Bridge Applications, Jiong Hu, George Morcous, Akbota Aitbayeva

Nebraska Department of Transportation: Research Reports

This project presents a comprehensive overview of the essential aspects associated with the cast-in-place application of UHPC, including formwork requirements, surface preparation, mixing procedures, placing methods, curing techniques, grinding specifications, and mockup construction. Each section provides in-depth insights into specific guidelines and practices outlined by various regulatory bodies. The research team has developed training materials designed for a full-day workshop tailored to benefit both contractors and NDOT engineers. This workshop comprises key topics such as proportioning, batching, testing, and the placement of both non-proprietary and proprietary UHPC mixes, as well as hands-on experience in batching, testing, and placing UHPC. The …

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Lcc Mse Walls, Joel Smith Dec 2023

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. …

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Compressive And Flexural Tensile Strength Impacts Of Aluminum Shavings In Concrete, Ian Smith Dec 2023

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 …

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Rilem Tc 266-Mrp: Round-Robin Rheological Tests On High Performance Mortar And Concrete With Adapted Rheology—Evaluating Structural Build-Up At Rest Of Mortar And Concrete, Sofiane Amziane, Kamal Khayat, Mohammed Sonebi, Arnaud Perrot Oct 2023

Rilem Tc 266-Mrp: Round-Robin Rheological Tests On High Performance Mortar And Concrete With Adapted Rheology—Evaluating Structural Build-Up At Rest Of Mortar And Concrete, Sofiane Amziane, Kamal Khayat, Mohammed Sonebi, Arnaud Perrot

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This Paper Presents the Results of a Round-Robin Testing Program Undertaken by RILEM TC-266-Measuring Rheological Properties of Cement-Based Materials in May 2018 at the Université D'Artois in Bethune, France. Seven Types of Rheometers Were Compared; They Consisted of Four ICAR Rheometers, Viskomat XL Rheometer, EBT-V Rheometer, Sliding Pipe Rheometer (SLIPER), RheoCAD Rheometer, and 4SCC Rheometer, as Well as the Plate Test. This Paper Discusses the Results of the Evolution of the Static Yield Stress at Rest of Three Mortar and Five Concrete Mixtures that Were Determined using Two ICAR Rheometers, Viskomat XL, and EBT-V Rheometers, as Well as the Plate …

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Load Determination, Strengthening, And Behavior Study Of Prestressed Concrete Channel Bridge Girders In South Carolina, Elhussien Khaled Elbatanouny Oct 2023

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 …

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Utilizing Waste Latex Paint Toward Improving The Performance Of Concrete, Mohamed Leithy, Eslam Gomaa, Ahmed A. Gheni, Mohamed Elgawady Aug 2023

Utilizing Waste Latex Paint Toward Improving The Performance Of Concrete, Mohamed Leithy, Eslam Gomaa, Ahmed A. Gheni, Mohamed Elgawady

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

In this paper, incorporating the waste latex paint (WLP) into the conventional concrete as a partial replacement of sand to improve its durability was investigated. The fresh and hardened characterizations, in addition to the durability of concrete, were examined. The slump test was used to evaluate the fresh properties, while the hardened properties were evaluated through the volume of voids and absorption rate, in addition to the compressive, splitting tensile, and flexural strengths tests. The durability performance was evaluated by the surface resistivity, bulk electrical resistivity, as well as freeze and thaw resistance tests. The results showed a reduction in …

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Experimental Investigation Of Water Quality Impact On The Compressive Strength Of Concrete, Shayan Sharifzad Aug 2023

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 …

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Nonlinear Impact-Echo Test For Quantitative Evaluation Of Asr Damage In Concrete, Clayton Malone, Hongbin Sun, Jinying Zhu Jun 2023

Nonlinear Impact-Echo Test For Quantitative Evaluation Of Asr Damage In Concrete, Clayton Malone, Hongbin Sun, Jinying Zhu

Department of Civil and Environmental Engineering: Faculty Publications

Nonlinear acoustic methods demonstrate high sensitivity for concrete damage evaluation. Among these methods, nonlinear resonance acoustic methods have been widely used in laboratory tests on small scale test samples. In this study, a nonlinear impact-echo (IE) method was proposed for concrete damage evaluation, in which the IE frequency shift was measured at different impact force levels. The nonlinear IE test is similar to the nonlinear impact resonance acoustic spectroscopy (NIRAS) test in the experimental setup and analysis method. How- ever, the nonlinear IE test excites a local thickness resonance mode of a member instead of the global resonance vibration. Therefore, …

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Slab Extension At Woods Humane Society, Corey K. Smith Jun 2023

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 …

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Optimal Concrete Mix Design And Finish For Skateboarding Performance, Lohgan Christoper Spencer Jun 2023

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 …

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City Farm Slo ‘Garden For All’ – Shade Structure, Reed Aitken Jun 2023

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 …

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Effects Of Admixes On The Compressive Strength Of Permeable Concrete, James T. Lyon Jun 2023

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” …

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Optimization Of The Self-Healing Efficiency Of Bacterial Concrete Using Impregnation Of Three Different Precursors Into Lightweight Aggregate, Omar Omar May 2023

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 …

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