Thesis (Ph. D.)--University of Texas at Austin, 2001. / Vita. Includes bibliographical references (leaves 156-172). Available also in a digital version from Dissertation Abstracts.

Thesis (M.S.)--Mississippi State University. Department of Computer Science. / Title from title screen. Includes bibliographical references.

The durability of infrastructure components, such as prestressed concrete bridge beams, can be significantly affected by long-term deterioration associated with corrosion. Corrosion is a major concern for bridges in Virginia, due to the frequent use of deicing salts during the winter, as well as the number of structures in marine environments. The residual capacity of corrosion damaged prestressed I-beams and box beams needs to be accurately estimated to determine if damaged bridges need to be posted, and to help with making informed decisions related to repair, rehabilitation and replacement of damaged bridges. The initial stage of the research investigated the ability to determine the in-situ strength of members that have visible corrosion-related damage. In this stage, six corrosion-damaged beams were investigated. Prior to testing, the beams were visually inspected and damage was documented. The beams were then tested in the lab to determine their flexural strength. Following testing, samples of strands were removed and tested to determine their tensile properties while cores were taken to determine compressive strength. Powdered concrete samples were removed to perform chloride concentration tests. The tested strengths of the beams were compared to calculated strengths using two methods for damage estimation and two different calculation approaches. Two repair methods were then evaluated through large-scale experimental testing, aimed at restoring the strength of deteriorated prestressed concrete beams. The investigated repairs included External Post-Tensioning (PT) and Carbon Fiber Reinforced Polymer (CFRP) laminates applied to the bottom flange of beams for flexural strengthening. A total of five full-scale bridge members were tested to failure throughout this stage. All beams were subjected to monotonically increasing loads until failure. For beams repaired with external PT, the experimental test was accompanied by a detailed approach for determining the ultimate failure load, the ultimate stress in the external tendons, and the location of the failure. For beams repaired with CFRP, the experimental test was accompanied by a parametric study that was performed to determine the maximum reduction in flexural strength for which CFRP can be considered as a viable repair method to restore the lost capacity. This dissertation provides additional information on estimating the residual capacity of corrosion-damaged beams and shows the types of repair that can restore their original strength. With this information, Departments of Transportation (DOT) can properly determine what types of repair are a suitable for the damaged girders based on their level of corrosion. / Doctor of Philosophy / Many bridges in the United States were built using longitudinal members, called girders, made of prestressed concrete. In prestressed concrete, because concrete cannot resist high tensile forces, tensioned steel cables, called strands, are used to produce compression on the concrete member to improve its behavior when it is in service. Corrosion induces cracks in the concrete superstructure which accelerates the deterioration rate and can result in a partial loss of the concrete body and exposure of the embedded steel. This causes degradation in the load-carrying capacity of the bridge girders which raises a danger to vehicles, passengers, and pedestrians. The residual capacity of corrosion damaged prestressed I-beams and box beams needs to be accurately estimated to determine if damaged bridges need to be posted, and to help with making informed decisions related to repair, rehabilitation and replacement of damaged bridges. The initial stage of the research investigated the ability to determine the in-situ strength of members that have visible corrosion-related damage. In this stage, six corrosion-damaged beams were investigated. Prior to testing, the beams were visually inspected, and damage was documented. The beams were then tested in the lab. Following testing, samples of strands were removed and tested to determine their tensile properties while cores were taken to determine compressive strength. Powdered concrete samples were removed to perform chloride concentration tests. The tested strengths of the beams were compared to calculated strengths. Two repair methods were then evaluated through large-scale experimental testing, aimed at restoring the strength of deteriorated prestressed concrete beams. The investigated repairs included External Post-Tensioning (PT) and Carbon Fiber Reinforced Polymer (CFRP) sheets applied to the bottom of beams for flexural strengthening. A total of five full-scale bridge members were tested to failure throughout this stage. All beams were subjected to monotonically increasing loads until failure. For beams repaired with external PT, the experimental test was accompanied by a detailed approach for determining the ultimate failure load, the ultimate stress in the external tendons, and the location of the failure. For beams repaired with CFRP, the experimental test was accompanied by a parametric study that was performed to determine the maximum reduction in flexural strength for which CFRP can be considered as a viable repair method to restore the lost capacity. This dissertation provides additional information on estimating the residual capacity of corrosion-damaged beams and shows the types of repair that can restore their original strength. With this information, Departments of Transportation (DOT) can properly determine what types of repair are a suitable for the damaged girders based on their level of corrosion.

Corrosion is a concern in old prestressed concrete bridges, especially bridges built in marine environments. Corrosion induces cracks in the concrete superstructure which accelerates the deterioration rate and can result in a complete loss of the concrete cover and exposure of the reinforcing and prestressing steel. This causes degradation in the load-carrying capacity of the bridge girders. Consequently, decisions need to be made on whether to replace, retrofit, or load post these bridges. Extensive research has focused on the flexural strength of corroded prestressed concrete girders. This research studies the shear strength of corroded prestressed concrete girders which can, then, be expanded further to evaluate the possible retrofitting techniques for restoring, or enhancing, their shear strengths. Two old prestressed concrete girders built in the 1960's and 1970's were delivered to the Murray Structural Engineering Laboratory at Virginia Tech from two decommissioned bridges in Virginia. The two girders showed signs of deterioration due to corrosion. Non-destructive testing was performed to evaluate their in-situ conditions. For both girders, each end was tested in the lab in three-point loading condition to make full use of the girders. Shear capacities of the girders were predicted using four methods in the current AASHTO LRFD and the ACI codes. In addition, analysis using Response2000 and strut-and-tie modelling were also carried out. Evaluation of these methods and comparisons with the experimental results were performed to reach to conclusions and recommendations for future work. Corrosion in strands seemed to not have as much influence on the shear capacity as on the flexural capacity. Destructive shear tests indicated that the actual shear capacities of the girders investigated in this research exceeded nominal capacities predicted by the current codes. However, the flexural capacities were reduced. Possible reasons for the girders' behaviors are discussed. / Master of Science / Many bridges in the United States were built using longitudinal members, called girders, made of prestressed concrete. In prestressed concrete, because concrete cannot resist high tensile forces, tensioned steel cables, called strands, are used to produce compression on the concrete member to improve its behavior when it is in service. Corrosion is a concern in old prestressed concrete bridges, especially bridges built in marine environments. Corrosion induces cracks in the concrete superstructure which accelerates the deterioration rate and can result in a partial loss of the concrete body and exposure of the embedded steel. This causes degradation in the load-carrying capacity of the bridge girders which raises a danger to vehicles, passengers, and pedestrians. Consequently, decisions need to be made by authorities on whether to replace, repair, or load post these bridges. Two main types of loads exist in bridge girders, namely shear forces and bending moments. Extensive research has focused on the ability of corroded prestressed concrete girders to resist stresses produced by moment, or flexure. However, bridge girders must also resist shear forces. This research studies the shear strength of corroded prestressed concrete girders which can, then, be expanded further to evaluate the possible retrofitting techniques for restoring, or enhancing, their shear strengths. Two old prestressed concrete girders built in the 1960's and 1970's were delivered to the Murray Structural Engineering Laboratory at Virginia Tech from two decommissioned bridges in Virginia. The two girders showed signs of deterioration due to corrosion. These signs include concrete losses, cracks, areas of unsound concrete, and exposed strands. Non-destructive testing was performed on the girders to evaluate the severity of their in-situ conditions. Then, two destructive full-scale tests were performed on each girder in the lab to estimate their actual shear strengths. Shear strengths of the girders were also predicted using four methods present in the current American Association of State Highway and Transportation Officials, AASHTO, and the American Concrete Institute, ACI, codes. In addition, analyses using other advanced tools were also carried out. Evaluation of these methods and comparisons with the experimental results were performed to reach to conclusions and recommendations for future work. Corrosion in strands seemed to not have as much influence on the shear strength as on the flexural strength. Destructive shear tests indicated that the actual shear strengths of the girders investigated in this research exceeded nominal strengths predicted by the current codes, the AASHTO and the ACI. However, the flexural strengths were reduced. Possible reasons for the girders' behaviors are discussed.

The aim of the thesis is solving the new building of the Faculty of Fine Arts in Brno. The studied area is located on the borders of the city of Brno-Center and Brno-Žabovřesky. Define the plot street Veveří, Bulínova, Academická, Hrnčířská and Šumavská. Žabovřesky. Define the plot street Veveří, Bulínová, Academic, Pottery and Šumavská. The proposal involves two universities - the Faculty of Arts and Faculty of Forensic Engineering. The proposal builds on a new urban plan for the city of Brno, and also reflects the design of the new underground tram Diameter. The building complex is designed as a whole. The buildings of these schools have certain common facilities, such as a library, cloakroom, dining room, hall, utility room. The proposal builds on the competition program at the Academic square in Brno. Parking is solved as an underground garage. Outside parking spaces for both faculties be reckoned with parking spaces for the City, and to be a substitute for the parking areas located on the currently designed plot. The proposed solution allows to stage construction, where the first stage will be built Faculty of Forensic Engineering, common areas, all the parking spaces and the second stage will be built Faculty of Fine Arts.

Thesis deals with problems of forensic technical analysis of traffic accidents, concretely with creation of complex methodology for analysis of traffic accidents of vehicles on the crossroad. There are defined terms of "complex system and complex analysis of traffic accident", technically acceptable range of important input values, systematization of accidents on the crossroad with methodologies in the thesis. Thesis shows problematical expert procedures, suggests scheme of expert evidence and includes methodology of measurement of common movement of vehicles on the crossroad and recommendation for expert procedures.

Problems exist with ethical decision-making in U.S. construction engineering projects. The purpose of this study was to explore factors that affect ethical decision-making in engineering construction in the United States. The general concepts of marketing ethics, Kohlberg's discussion of ethical and moral reasoning development, and Gillian's discussion of ethical care served as the basis of the conceptual framework. Factors that inhibit ethical decision making were addressed in the research questions. The resulting narrative framework included implementable initiatives based on these factors that could improve the quality of ethical decision-making and the impact of these initiatives on the cost and quality of construction engineering projects. The use of qualitative grounded theory design led to findings from the research questions and enabled the development of a theory to explain the phenomenon. The research was based on data collected from interviews with a purposive sample of 12 civil engineers with 15 to 45 years of forensic and managerial experience with construction engineering projects. The constant comparative method was used to analyze the data. The principal finding from the research was that unethical decision-making in the legal and political systems undermines the image and authority of construction engineers in the United States. The findings of the study may cause social change by indicating how to enhance the ethical behavior of individuals involved in decision-making within the U.S. construction engineering industry, leading to improvements in the cost and quality of construction projects that benefit individual stakeholders as well as society.

The traditional approach to a digital investigation when a computer system is encountered in a running state is to remove the power, image the machine using a write blocker and then analyse the acquired image. This has the advantage of preserving the contents of the computer’s hard disk at that point in time. However, the disadvantage of this approach is that the preservation of the disk is at the expense of volatile data such as that stored in memory, which does not remain once the power is disconnected. There are an increasing number of situations where this traditional approach of ‘pulling the plug’ is not ideal since volatile data is relevant to the investigation; one of these situations is when the machine under investigation is using encryption. If encrypted data is encountered on a live machine, a live investigation can be performed to preserve this evidence in a form that can be later analysed. However, there are a number of difficulties with using evidence obtained from live investigations that may cause the reliability of such evidence to be questioned. This research investigates whether digital evidence obtained from live investigations involving encryption can be considered to be reliable. To determine this, a means of assessing reliability is established, which involves evaluating digital evidence against a set of criteria; evidence should be authentic, accurate and complete. This research considers how traditional digital investigations satisfy these requirements and then determines the extent to which evidence from live investigations involving encryption can satisfy the same criteria. This research concludes that it is possible for live digital evidence to be considered to be reliable, but that reliability of digital evidence ultimately depends on the specific investigation and the importance of the decision being made. However, the research provides structured criteria that allow the reliability of digital evidence to be assessed, demonstrates the use of these criteria in the context of live digital investigations involving encryption, and shows the extent to which each can currently be met.

The traditional approach to a digital investigation when a computer system is encountered in a running state is to remove the power, image the machine using a write blocker and then analyse the acquired image. This has the advantage of preserving the contents of the computer’s hard disk at that point in time. However, the disadvantage of this approach is that the preservation of the disk is at the expense of volatile data such as that stored in memory, which does not remain once the power is disconnected. There are an increasing number of situations where this traditional approach of ‘pulling the plug’ is not ideal since volatile data is relevant to the investigation; one of these situations is when the machine under investigation is using encryption. If encrypted data is encountered on a live machine, a live investigation can be performed to preserve this evidence in a form that can be later analysed. However, there are a number of difficulties with using evidence obtained from live investigations that may cause the reliability of such evidence to be questioned. This research investigates whether digital evidence obtained from live investigations involving encryption can be considered to be reliable. To determine this, a means of assessing reliability is established, which involves evaluating digital evidence against a set of criteria; evidence should be authentic, accurate and complete. This research considers how traditional digital investigations satisfy these requirements and then determines the extent to which evidence from live investigations involving encryption can satisfy the same criteria. This research concludes that it is possible for live digital evidence to be considered to be reliable, but that reliability of digital evidence ultimately depends on the specific investigation and the importance of the decision being made. However, the research provides structured criteria that allow the reliability of digital evidence to be assessed, demonstrates the use of these criteria in the context of live digital investigations involving encryption, and shows the extent to which each can currently be met.

The theme of the thesis is a study of the project of the Faculty of Fine Arts in Brno. The site lies on boundary of two city parts, Brno – Střed and Brno – Žabovřesky and it is surrounded by streets Veveří, Šumavská and Bulínova.The project ties together with architectural study from subject TG02, which concerns the Faculty of Forensic Engineering. The final result of both parts is the project of both schools with common facilities. The part of the project is an underground garage where is a space for public parking which is demanded by city hall. The main idea was to create building with respect to surroundings and define itself to the street lines and create the small square inside the block of the buildings. The results are two six-floor buildings connected by two-floor object with atrium.