Civil Engineering Commons^™

Interdisciplinary Student Competition For California Polytechnic State University - San Luis Obispo, Forest G. Gobble

Construction Management

Cal Poly has a reputation for producing some of the best qualified graduates in their respective fields of study. While this is very important, curricular activities involving collaboration between students within the same college are limited (excluding same major). Beyond that, collaboration opportunities across colleges are even more rare. When graduates enter the workforce, many are thrust into highly collaborative environments across various disciplines. Industry professionals have shown a strong desire for young people who have had exposure to realistic problems and experience working with other professions outside of their own field of expertise. The question needing answering is, would …

Development Of A Mix Design Adjustment Method For Fiber Reinforced Concrete And Super High Performance Concrete Based On Excess Paste, Joe Malloy

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

The main objective of this study was to develop a mix design adjustment method for Fiber Reinforced Concrete (FRC) that would maintain appropriate workability while improving hardened concrete performance. A literature review was conducted to examine existing methods for adjusting mix designs to account for fiber introduction. It was found that while increasing fine aggregate and cement paste content can make up for lost workability with the addition of fibers, no rational mix design adjustment method is available. Reference mix designs from the Nevada Department of Transportation and the Nebraska Department of Transportation were used, and this study focused on …

Multi-Facet Retrofit Approach To Improve Energy Efficiency Of Existing Class Of Single-Family Residential Buildings In Florida, Kwame Baffour Ohene Amoah

Theses and Dissertations

There are many approaches to incorporate energy efficiency measures (EEMs) into building through retrofit projects. Single-family buildings are an essential target for energy improvements because of their energy-saving potential and considerable market share. This study evaluates energy savings and cost-effectiveness of individual retrofit options. It proposes energy efficiency measures for an existing class of single-family homes constructed between the years of 1950 and 1970. The study uses a baseline building located in Melbourne, FL, as a case study. A survey via clustering data mining was conducted on Florida Single-Family Residential (SFR) buildings (1950 – 1970) to establish patterns of construction, …

Green Up Pavement Rehabilitation Design Tool, Dragos Andrei, Robert E. Kochan, Jose H. Perez

Mineta Transportation Institute

While designers produce pavement rehabilitation recommendations every day, for projects of all sizes, most designers have little information on the environmental impact of their recommendations. This research developed a new decision tool, called the “Green Up Pavement Rehabilitation Design Tool,” to allow the comparison of different rehabilitation solutions in terms of greenhouse gas emissions and to encourage sustainable practices such as materials recycling and the use of permeable, cool, and quiet pavement surfaces. The project aligns with the major goal of California Senate Bill 1, which is “to address deferred maintenance on the state highway system and the local street …

Analyzing Impacts Of Transportation And Non-Transportation Activities On Human Health With An Advanced Platform For Collecting Travel And Physical Activity Data, Raed Abdullah Hasan

Dissertations

Recently much attention is paid to the lack of physical activities that may cause the health problems in many counties. Travel activities provide a certain amount of physical activities, and the active transportation, such as walking and cycling, becomes more important as an essential element of transportation. The active transportation is expected to contribute to improving human health by reducing cardiovascular disease, obesity, and premature death. However, detailed relationship between the transportation choices and human health has not been well understood. Therefore, there is a need for investigating traveler behaviors and how their choices affect physical activities and public health. …

Safety Assessment Of Road Vehicle In Crosswind Considering Driver Behavior, Jiexuan Hu

LSU Doctoral Dissertations

With expansion of the economy, more and more highway networks extend to coastal areas and mountain valley areas. Vehicles will be exposed to strong crosswinds when driven on these highway roads, especially in hurricane season and in winter in these two different topographic areas. Strong crosswinds threaten the safety of transportation infrastructure and passing vehicles in forms of vehicle accidents that usually result in traffic blockage and driver injury, posing negative effects on economic growth. This dissertation aimed to evaluate the vehicle safety when running through crosswinds in consideration of driver behaviors.

Firstly, the aerodynamic characteristics of road vehicles were …

A Practitioner’S Guide To Small Unmanned Aerial Systems For Bridge Inspection, Sattar Dorafshan, Robert J. Thomas, Calvin Coopmans, Marc Maguire

Electrical and Computer Engineering Faculty Publications

Small unmanned aerial system(s) (sUAS) are rapidly emerging as a practical means of performing bridge inspections. Under the right condition, sUAS assisted inspections can be safer, faster, and less costly than manned inspections. Many Departments of Transportation in the United States are in the early stages of adopting this emerging technology. However, definitive guidelines for the selection of equipment for various types of bridge inspections or for the possible challenges during sUAS assisted inspections are absent. Given the large investments of time and capital associated with deploying a sUAS assisted bridge inspection program, a synthesis of authors experiences will be …

The Development Of A Novel Experiment On Confined, Flattened Brazilian Disks To Correlate Damage And Permeability In Brittle Geo-Materials, Samuel H. Boyce

Civil Engineering ETDs

This research develops a novel experiment using flattened Brazilian disks under confining pressure with concurrent permeability measurements and acoustic emission monitoring. The purpose of this work is to correlate damage and permeability in brittle geo-materials. Two series of tests are performed on concrete and one series on tuff, under a range of confining stresses between 2.76 and 13.79 MPa. Tests were continued beyond peak stress conditions, capturing data in the post-peak region. The acoustic emission data (cumulative energy and counts) are used to identify damage thresholds and track the progression of microscopic damage. This quantified damage is then correlated to …

Dynamic Prediction Of Runway Configuration And Airport Acceptance Rate, Yuan Wang

USF Tampa Graduate Theses and Dissertations

Automated prediction of runway configuration and airport capacity is critical for the future generation of air traffic management. In the future aviation industry, multi-sources weather forecast information will be available for air traffic decision-making units; how to use these data efficiently is key for overall efficiency of air traffic management. Currently, air traffic management personnel lack tools to assist them to translate weather forecast data into real-time airport capacity. Runway configurations and AARs of airports in a multi-airport system are determined by different air traffic controller personnel. The lack of synchronization may lead to the loss of efficiency of the …

Enhancing Concrete Pavement Service Life Using Multiple Strategies To Reduce Cracking Potential, Dhanushika Mapa Mudiyanselage

USF Tampa Graduate Theses and Dissertations

Over the past years, prevention of cracking in concrete structures, especially at early age, has been a challenge facing transportation agencies. During early age, restraint of thermal and moisture related volume changes causes cracking in concrete. This research focuses on evaluating the effectiveness of different cracking mitigation strategies that can be implemented, in different concrete elements, to reduce early-age cracking incidents and therefore enhance concrete service life. To this end, a battery of field and laboratory testing were conducted, and finite element analysis was performed to better understand the mechanisms of primary significance on minimizing cracking risks commonly associated with …

Damage Evaluation Of Full-Scale Rc Slab By Ultrasonic Tomography, Hiroshi Hayashida, Tamon Ueda

International Conference on Durability of Concrete Structures

There have been reports of road bridges that deteriorated after their RC slabs had been repaired. The insufficient removal of damaged materials is said to be the cause of such post-repair deterioration. Consequently, there is a call for a survey method that can detect deteriorated materials of bridges with high accuracy. Towards the development of such a method, this report focuses on ultrasonic tomography, because it can detect damage to the RC slabs of road bridges over relatively large areas. We examined the applicability of ultrasonic tomography to a method of assessing the RC slab damage by a test that …

Integrated Sensor Network For Monitoring Steel Corrosion In Concrete Structures, José Enrique Ramón-Zamora, José Manuel Gandia-Romero, Román Bataller, Ana Martínez-Ibernón, Isabel Gasch, Juan Soto

International Conference on Durability of Concrete Structures

The developed Integrated Sensor Network (ISN) allows a non-destructive monitoring of the rebar condition at different parts of the structure. The corrosion sensor allows the accurate determination of the corrosion rate (µm/year). Moreover, additional sensors are integrated in order to detect relevant changes in the concrete electrochemical condition.

The ISN has been published as an international invention patent (reference number WO 2016/177929 A1). The system is based on an economic, simple, reliable and durable technology, which makes its implementation viable on new and repaired reinforced concrete structures (RCS). Therefore, it is also possible monitoring non-accessible parts such as deep foundations …

Similarity Analysis Of Rebar Corrosion Under Different Electrochemical Accelerated Method, Chuanqing Fu, J Chen, X Jin, H Ye, Jun Zhu

International Conference on Durability of Concrete Structures

The concrete cover cracking caused by non-uniform corrosion of reinforcing bar is one of the most important reason for structure service performance degradation. The most widely used electrochemical accelerated corrosion methods include external and internal electrode methods. The reinforcement are used as anode in both methods. The different between two methods is the position of auxiliary. In external electrode method, the auxiliary is set outside the specimen, including three methods, i.e. samples whole/part submerged in saline, samples wrapped by sponge and steel mesh. The electrochemical mechanism of these four accelerated method were analyzed by using the FE software COMSOL. According …

Micro-Mechanical Analysis Of Corrosion Products Formed During Long-Term Carbonation Induced Corrosion Of Steel, Marijana Serdar, Dubravka Bjegovic, Valérie L’Hostis, Stéphane Poyet, Damien Féron

International Conference on Durability of Concrete Structures

During corrosion distinct types of corrosion products form, composed of different ratios of ferrous ions and oxide, hydroxides. Corrosion products have different physical and mechanical properties, mainly density, resistivity, volume and modulus of elasticity compared to iron. Knowing properties of corrosion products is indispensable for service life modelling of structures and can give valuable insight into the long-term corrosion propagation process. In this study micro-indentation method was used to evaluate mechanical properties of different layers formed during long-term carbonation induced corrosion of steel in concrete. Investigation was performed on three sets of reinforced concrete samples, that underwent corrosion during 50, …

An Experimental Study Of Concrete Resistivity And The Effects Of Electrode Configuration And Current Frequency On Measurement, Hayder Oleiwi, Yu Wang, Nan Xiang, Levingshan Augusthus-Nelson, Xianyi Chen, Igor Shabalin

International Conference on Durability of Concrete Structures

Electrical resistivity, a measurable parameter of the state of concrete, plays an important role in the assessment of reinforced concrete structures. An experimental study using two-electrode method has been conducted to evaluate the resistivity of Portland cement concrete. Internal and external electrodes were varied in order to understand effect of the electrodes configuration, where carbon fibre (CF) sheets were employed as the internal electrodes and CF and copper sheets were used as external electrodes. Furthermore, frequency of applied current was varied from low to high, to identify the most suitable frequency that can be utilized for stable and reliable results. …

Will Blended-Cement Systems With Similar Chloride Penetration Potentials Resist Similarly To Corrosion?, William Wilson, Vincent Labattaglia, Arezki Tagnit-Hamou, Luca Sorelli

International Conference on Durability of Concrete Structures

The capacity of concrete to prevent chloride ions penetration represents a key durability factor for steelreinforced structures exposed to de-icing salts and/or marine environments. Although blended-cement systems are commonly characterized with accelerated chloride penetration tests developed for Portlandcement concrete (e.g. the ASTM C1202 method), their microstructures and pore solutions are very different. This study aims to illustrate how the full potential of blended-cement systems to resist chloride ingress (and thus, chloride-induced corrosion) may not be justly disclosed by these accelerated tests using electrical current, even when tested after three months of curing. A Portland-cement-only mortar and five binary blended-cement mortars …

An Investigation On Moisture And Water Absorption In Cement Paste With Electrical Resistance Method, Manami Mizoguchi, Tatsuya Kitagawa, Totsawat Daungwilailuk, Yuko Ogawa, Kenji Kawai

International Conference on Durability of Concrete Structures

Moisture in concrete is one of main factors related to degradation and deterioration of concrete structure, and there are various moisture transport phenomena in concrete such as drying and absorbing. There are a lot of previous studies on the drying process of concrete to clarify the mechanisms of creep as well as shrinkage. However, few studies have been reported on the process of water absorption and moisture absorption although carbonation and chloride attack are strongly related to moisture and water absorbing. It is necessary to investigate moisture transfer in concrete in detail. This study investigated the moisture transfer in moisture …

Pore Characteristics And Computed Permeability Of Pastes Subject To Freeze-Thaw Cycles At Very Early Ages By X-Ray Ct, Ya Wei, Zehong Wu, Xiang Gao

International Conference on Durability of Concrete Structures

Freeze-thaw cycling can damage microstructure of concrete and reduce the service life of concrete structures. This is especially detrimental for concrete subject to freeze-thaw cycles at very early-ages, such as within the first few days after constructions. Typical low and high water-to-cement (w/c) ratio pastes are investigated experimentally and numerically in this study. The pastes are subject to freeze-thaw cycles at the age of 1, and 7 days and then sealed-cured to the age of 45 days. The pore size distribution is measured and quantified by X-ray computer tomography (CT) with high resolution. The permeability of the corresponding pastes is …

Investigation Of Microstructure Of Cementitious Materials Exposed To High Temperature By Non-Destructive Integrated Ct-Xrd Method, Takuya Mikami, H Takahashi, T Sugiyama

International Conference on Durability of Concrete Structures

Severe accident occurred in 2011 at the Fukushima Daiichi nuclear power plant and it can be assumed that the concrete building was exposed to high temperatures environment for a long time due to loss of the cooling function of the nuclear reactor. In order to prepare for the best scenario in the decommission plan, it should be first needed to clarify and evaluate the level of damage and deterioration of the contaminated concrete. To solve this problem, experiments were conducted for cementitious materials with the maximum temperature of 400 or 1000 degrees Celsius with durations of up to 2 hours. …

Influence Of Pore Structure On Relative Chloride Diffusion Coefficient In Unsaturated Cementitious Materials, Yong Zhang, Guang Ye

International Conference on Durability of Concrete Structures

Chloride-induced corrosion of reinforcement in concrete structures is a serious issue in engineering practice. This paper investigates the influence of pore structure on the relative chloride diffusion coefficient Drc in unsaturated cementitious materials. The effects of various pore features, including porosity, pore size, and pore connectivity, on the continuity of water-filled pores in unsaturated porous systems are analyzed based on the Kelvin law and water desorption process. In the experimental program, different cementitious materials (OPC, slag, fly ash, and limestone powder) were used to prepare paste and mortar samples. The Drc of the mortar samples (one year old) at various …