Vehicle collisions with bridge piers can result in significant damage to the support pier and potentially lead to catastrophic failure of the whole structure. The Nation’s aging infrastructure suggests that many structures no longer meet current design standards, placing many bridge susceptible to failure if subjected to an extreme loading event. This research aims to study the structural response of reinforced concrete bridge piers subjected to vehicle collisions. A sensitivity analysis is conducted to observe the causes of shear and bending failures of bridge piers subjected to vehicle collision. Parameters, such as pier diameter, transverse reinforcement spacing, vehicle impact velocity, pile cap height, and multi-pier configuration, are investigated in this study. The finite element code LS-DYNA is utilized to simulate and analyze the vehicle collisions to obtain accurate and detailed results. The vehicle models offered by the National Crash Analysis Center and the National Transportation Research Center, Inc. are used to conduct this research. The finite element modeling controls and material properties are validated by conducting an impact drop hammer experiment. The bridge pier collision models are validated by comparing vehicle damage and impact forces with published research results. Conservation of energy is also checked to assure stability within the impact simulation. A sensitivity analysis suggests that different pier parameters have a profound effect on failure modes and distribution of impact forces. Piers with large stiffness result in high impact forces, low lateral displacements, and high resistance to shear forces and bending moments. A performance-based analysis shows that bridge piers can be designed using damage ratios associated with particular damage states.

Yes / River dynamics and sediment transport play an important role in river bed morphology. Building a bridge pier along the river alters the cross-section of the river and causes the change in flow processes. These changes are mainly responsible for pier scour. In this paper, the usage of collars to reduce scour around circular piers has been investigated. The collars with different diameters and depth positions have been studied using previous data and additional data collected in the present study to assess their effectiveness in reducing scour. Using a wide range of measured data, an empirical equation to compute the maximum scour depth around the circular piers in the presence of collars has been proposed. The proposed equation has been validated and proven to be applicable to a wide range of pier layouts. It has been found that the maximum efficiency can be achieved by fixing the collar at bed level and adopting a collar diameter 1.5–2.5 times of pier diameter.

No description available.

The purpose of this paper was to investigate the architectural appearance and the evolution of bridges. It is to show the intentions and consequent symbols of civilizations who built bridges. The paper also investigates bridge types, foundations and falsework. / Master of Architecture

William Langland's The Vision of Piers Plowman was probably the first medieval English poem to achieve a national audience because Langland chose to write in the vernacular and he used the specialized vocabularies of his readership to open the poem to them. During the late thirteenth and fourteenth centuries, writers began using the vernacular in an attempt to allow all English people access to their texts. They did so consciously, indicating their intent in prologues and envois when they formally address readers. Some writers, like Langland and the author of Mankind, actually use representatives of the rural classes as primary characters who exhibit the beliefs and lives of the rural population. Anne Middleton's distinction between public-the readership an author imagined-and audience-the readership a work achieved-allows modern critics to discuss both public and audience and try to determine how the two differed. While the public is always only a presumption, the language in which an author writes and the cultural events depicted by the literature can provide a more plausible estimate of the public. The vernacular allowed authors like Gower, Chaucer, the author of Mankind, and Langland to use the specialized vocabularies of the legal and rural communities to discuss societal problems. They also use representatives of the communities to further open the texts to a vernacular public. These open texts provide some representation for the rural and common people's ideas about the other classes to be heard. Langland in particular uses the specialized vocabularies and representative characters to establish both the faults of all English people and a common guide they can follow to seek moral lives through Truth. His rural character, Piers the Plowman, allows rural readers to identify with the messages in the text while showing upper class and educated readers that they too can emulate a rural character who sets a moral standard.

Ng Kit Ping Joey. / On double leaves. / "Architecture Department, Chinese University of Hong Kong, Master of Architecture Programme 2001-2002, design report." / Includes bibliographical references (leaves 106). / Chapter PART I --- 2001 fall term / Chapter 01 --- issues studies / Chapter i. --- the phenomena of shopping --- p.(04 -13) / Chapter ii. --- shopping - a predator --- p.(14 - 23) / Chapter iii. --- mall system --- p.(24 - 33) / Chapter 02 --- case studies --- p.(34 - 40) / Chapter 03 --- site selection / Chapter i. --- north point ferry pier --- p.(42 - 46) / Chapter ii. --- wanchai ferry pier --- p.(47 -55) / Chapter 04 --- prelim design proposal --- p.(56 - 61) / Chapter PART II --- 2002 spring term / Chapter 01 --- design development - feb 07 external review --- p.(64 - 74) / Chapter 02 --- design exploration --- p.(75 - 78) / Chapter 03 --- final design - apr 20 final review --- p.(79 - 95) / Chapter PART III --- appendix / Chapter 01 --- appendix / Chapter i. --- new central waterfront --- p.(97 -103) / Chapter ii. --- the history of star ferry service --- p.(104) / Chapter iii. --- no. of fixed route passenger journeys --- p.(105) / Chapter 02 --- bibliography --- p.(106) / Chapter 03 --- acknowledgement --- p.(107)

No description available.

Master of Science / Department of Architectural Engineering and Construction Science / Kimberly W. Kramer / Soils conditions vary throughout the United States and effect the behavior of the foundation system for building structures. The structural engineer needs to design a foundation system for a superstructure that is compatible with the soil conditions present at the site. Foundation systems can be classified as shallow and deep, and behave differently with different soils. Shallow foundation systems are typically used on sites with stiff soils, such as compacted sands or firm silts. Deep foundation systems are typically used on sites with soft soils, such as loose sands and expansive clays. A parametric study is performed within this report analyzing tilt-up concrete structures in Dallas, Texas, Denver, Colorado, and Kansas City, Missouri to determine the most economical tilt-up wall panel and foundation support system. These three locations represent a broad region within the Midwest of low-seismic activity, enabling the use of Ordinary Precast Wall Panels for the lateral force resisting system. Tilt-up wall panels are slender load-bearing walls constructed of reinforced concrete, cast on site, and lifted into their final position. Both a 32 ft (9.75 m) and 40 ft (12 m) tilt-up wall panel height are designed on three foundation systems: spread footings, continuous footings, and drilled piers. These two wall heights are typical for single-story or two-story structures and industrial warehouse projects. Spread footings and continuous footings are shallow foundation systems and drilled piers are a deep foundation system. Dallas and Denver both have vast presence of expansive soils while Kansas City has more abundant stiff soils. The analysis procedure used for the design of the tilt-up wall panels is the Alternative Design of Slender Walls in the American Concrete Institute standard ACI 318-05 Building Code and Commentary Section 14.8. Tilt-up wall panel design is typically controlled by lateral instability as a result from lateral loads combining with the axial loads to produce secondary moments. The provisions in the Alternative Design of Slender Walls consider progressive collapse of the wall panel from the increased deflection resulting from the secondary moments. Each tilt-up wall panel type studied is designed in each of the three locations on each foundation system type and the most economical section is recommended.

published_or_final_version / Civil Engineering / Master / Master of Philosophy

The Medieval English dream vision evidence influences from a variety of earlier vision literature, notably the apocalyptic vision and narrative dream. Philosophical visions by Plato, Cicero and Boethius, and Christian revelations of John and Paul contain traits that found their way into the dream poems by Langland, the Pearl poet and Chaucer. The Norwegian ballad Draumkvedet exhibits features that mirror these English visions. Notable characteristics pertaining to the character of the dreamer, the interplay between dreamer and dream, imagery of the vision, and structure, point to a common set of generic influences. Comparing Draumkvedet with its English counterparts demonstrates that they stem from the same tradition. Draumkvedet bares special resemblance to the Dream of the Rood, Piers Plowman and Pearl in its exploration of Christian doctrine and its appeal to the audience.