Thesis (M.S.)--Oregon State University, 1987. / Typescript (photocopy). Includes bibliographical references (leaves 56-57). Also available on the World Wide Web.

Thesis (Ph. D.)--University of Texas at Austin, 2006. / Vita. Includes bibliographical references.

Thesis (Ph. D.)--University of Texas at Austin, 2007. / Vita. Includes bibliographical references.

Thesis (Ph. D.)--University of Texas at Austin, 2007. / Vita. Includes bibliographical references.

This thesis describes the results of an investigation into the effects of vertical alignment design standards upon the energy costs of constructing and operating major rural roads in the United Kingdom. Alternative road designs have been produced for a series of ground profiles, and for each of these designs the energy costs have been calculated. The construction energy cost has been calculated from the fuel consumption and production output of earthmoving plant. The energy costs of structures and surfacing was assumed to be constant for the design changes examined. The energy costs of operation were calculated from the results of fuel consumption tests undertaken by the author. These tests showed a clearer and more accurate relationship between gradient and fuel consumption than other tests undertaken in the United Kingdom. The alternative designs produced examined the effects of altering the standards for maximum gradient, minimum curve radii and length, formation width, minimum gradient, and side slope gradient. The effect of choosing an alternative route was also investigated. The results of the energy calculations for these alignments showed that in general, the more constrained the design, the lower the total energy costs. This conclusion is insensitive to changes in construction cost, but is highly sensitive to changes in vehicle numbers or types. For a motorway type design, the average flow on trunk and motorway roads, and a thirty year design life the maximum gradient standard that produced the minimum energy cost was about 1. 5 percent. This is considerably lower than used at present, and the most recent standard encourages the use of steeper gradients. This research suggests that vehicle operating costs are an important factor when designing the vertical alignment of a road, and that present methods do not accurately determine the effects of road design on vehicle costs.

The subject of this study is road investment in B.C. made through the Provincial Department of Highways in the years 19^6-71, The pattern of investment is described and is used to indicate policies and objectives being evolved over the period. An effort is also made to evaluate the impact of the investment in terms of the benefit to certain classes of road users. Data on investment were gathered from the Annual Reports of the Minister, and assembled according to area, item, time period and class of road. The nature of investment has been given close attention because it is felt that its role has been somewhat overlooked in the previous studies of the relationship between transport infrastructure and economic activity. That relationship has usually been treated in summary form, with highly generalized indices. There is an attempt in this study to find a rationale of spending to explain the variations between areas, and from which to draw inferences about policies. This leads on to closer examination of the trunk network. Some structural measures of improvement in the network were calculated, but were not very helpful. This study argues that the improvement has to be valued by some user before it is translated into increased accessibility and responses amongst economic activities. Because improvements mean different things to different users and non-users, different approaches to evaluation have to he taken. A large truck is chosen for the case of B.C., and operating costs are simulated for the roads existing in 1952, 1962 and 1971. The changes in truck operating costs are used to explore the meanings of ˈimprovementˈ and the ˈjustificationˈ of certain investments. An estimate of annual savings to trucks from road improvements is derived from the simulated costs. The approach through investment is found to aid understanding of route and network development. It provides criteria by which to evaluate other aspects of road development, such as the road needs of certain populations, and the effects of external connections and through paths. It reveals the highly variable per mile cost of links, and emphasizes the interdependence of different types of spending. It suggests a relationship between inter-urban and local spending and traffic, which should be worth following up in other situations. Among other things, it is discovered that there has been a tendency to spend an increasing proportion on the branch or feeder roads. In the last few years, there has been an increasing concentration on urban or near-urban roads for the relief of congestion. The purposes of roads and routes are seen to change over time. The pattern of spending has been much affected by the difficulty of road construction in B.C. Increases in election years have stood out markedly. These have ˈcostˈ the Province a significant amount through inflated contract prices. Some suggestions are made on how over-the-road savings could make their way through to freight rates, schedules and services, and thus affect the client economic activities. The estimate of annual savings of $15-20 million to large trucks is a conservative and partial measure of benefit. The aim was not a definitive measure of improvement and partial benefit, but to use the measure in different contexts and reveal the different meanings and quantities of improvement. Different ˈjustificationsˈ for link investment were provided from different perspectives. The interdependence of links and of investment allocations in the total system was emphasized. It is the main strength of this modified network perspective that it allows the simultaneous consideration of flows, structure, link importance and nodal accessibility. / Arts, Faculty of / Geography, Department of / Graduate

Two critical components of the United States civil infrastructure, bridges and roads, have deteriorated in the past two decades at an accelerated rate and are in need of maintenance and rehabilitation. Geosynthetics may have the potential to provide a long-term solution to some of the problems that are present in these roads and bridges. When installed properly, some geosynthetics can act as both a moisture barrier and stress absorption layer. However, the tack coat application rate is critical as an excessive amount can cause eventual slippage, while too little may result in debonding. A new geocomposite membrane, which is comprised of a low modulus PVC layer sandwiched between two layers of nonwoven geotextile, has recently been introduced for use in highway systems for water impermeability and strain energy absorption. A laboratory testing program was conducted to determine the optimum asphalt binder tack coat rate that needs to be applied in the field. To accomplish this, a fixture was designed to allow the application of cyclic shear loading at the geocomposite membrane interface when used as an interlayer simulating one of two situations: a concrete bridge deck overlaid with the geocomposite membrane, and an HMA overlay or a flexible pavement with the geocomposite membrane sandwiched between an HMA base layer and an HMA wearing surface. The research concluded that 1.40 kg/m2 of tack coat should be used when the geocomposite surface is in contact with an HMA base mix, 1.5 kg/m2 should be used when it is in contact with an HMA surface mix, and 1.75 kg/m2 should be used when it is in contact with concrete surfaces. However, these tack coat application rates are a function of the structural material type and the tack coat material type (binder performance grade). In addition, an analysis of the simulated bridge deck specimens with geocomposite membrane and the control samples, containing no membrane, shows distinct evidence that the membrane acts as a stress-absorbing material. / Master of Science

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