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The utilisation of rock bolting for the support of British coal mine roadways can improve roadway strata conditions and, by permitting a reduction in the density, cross-section or total elimination of steel standing support, can produce considerable savings in roadway support costs. This study reviews worldwide experiences in the use of rock bolt reinforcement techniques to enhance the stability of coal mine roadways. Details of methods of geotechnical design data acquisition and assessment are given as well as a critical study of various empirical, analytical and observational methods of tunnel support design. The use of scale model studies is shown to be particularly effective for the design of rock bolt support systems for coal mine roadways. With reference to numerous case studies, descriptions are given of rock bolt systems available and their suitability to specific mine roadway conditions is discussed. Installation procedures and equipment are also reviewed. It is the author's intention that this study should be used as the basis for further detailed investigation of specific aspects of rock bolt support systems. A number of recommendations are made as to the fields in which further research should be undertaken.

All roadway agencies monitor and maintain their infrastructure as it deteriorates over time. Agencies allocate the money that they have for maintenance, rehabilitation and reconstruction operations across their entire network. Regular and timely maintenance and rehabilitation treatments can postpone the need for reconstruction on a roadway. The need for infrastructure sustainability has been brought to the forefront of society and has become an important part of any public agency’s decision making processes. To achieve sustainable roadways social, economic and environmental benefits must be achieved while maintaining technically sound solutions. By considering the amount of energy that is consumed and the amount of greenhouse gas (GHG) emissions generated through various roadway treatments, sustainability can be brought into the decision making process. The objective of this research was to develop a probabilistic model that quantifies the amount of energy that is consumed and carbon dioxide equivalents (CO2e) generated for typical roadway construction, maintenance, rehabilitation and reconstruction projects in Saskatchewan and Alberta. The model constructed within this work was divided into three sub-models: 1) material production, 2) equipment usage and 3) material transport. For every variable that was required to be entered into each sub-model, a low, average or most likely and high value was determined. By using a range of input values the uncertainty of the values entered was incorporated and sensitive parameters were identified. A base case study of a one lane-kilometer (lane-km), 3,700 m2, section of rural roadway was analyzed. For the initial construction of a lane-km of traditional flexible pavement roadway it was determined that 1,870 GJ (giga joules) of energy is required. Based on an annual average amount of energy used per home in Saskatchewan, 126 GJ/year, 1,870 GJ would power approximately 15 homes for one year. Similarly it was determined that 152.4 tonnes (t) CO2e are emitted for the construction of a lane-km of traditional flexible pavement roadway. Based on an average CO2e generation value of 5.1 t per passenger vehicle per year the GHG emissions generated from the construction of a lane-km of roadway is equivalent to the GHG emissions released by approximately 30 passenger vehicles over one year. It was also determined that the volume of CO2e generated for initial construction compared to the volume of material in the roadway was a ratio of 30 to 1. The base case study also reviewed various maintenance, rehabilitation and reconstruction treatments for the amount of energy consumed and GHG emissions generated for one lane-km. From the modeled values it was found that the order of energy consumed and CO2e generated from least to greatest for maintenance treatments is: fog seal, slurry seal, micro surfacing, single, double and triple chip seal and ultra thin overlay. For rehabilitation and reconstruction treatments the order of energy consumed and CO2e generation from least to greatest is: cold in-place recycling, mill and fill, full depth reclamation, remove and replace with recycled materials and remove and replace with virgin materials. Through a sensitivity analysis of the input parameters, it was observed that for maintenance treatments the sensitive parameters were the equipment efficiency (EFE) value, the placement rate of the treatment, the aggregate application rate and the amount of asphalt binder included in the treatment. For rehabilitation and reconstruction treatments, the two most sensitive parameters were the asphalt concrete plant energy and the application rate of the Portland cement. Further investigation into how each sub-model contributed to the overall amount of energy consumed and CO2e generated found the production of materials contributed the greatest to the overall values. When examining the production of each layer in a traditional flexible pavement roadway structure, the asphalt layers contributed the greatest to the energy consumed at 72.1 percent of all materials produced. The asphalt layers also contributed the greatest to the GHG emissions generated from the production of materials at 42.7 percent. Further breaking down the production of the asphalt layers, the energy requirements at the hot mix asphalt concrete plant account for 75.9 percent of the energy consumed and 52.0 percent of the CO2e generated for the production of the materials of the asphalt layers. The cost of each treatment was reviewed based on the cost of diesel at $1.21/litre and the amount of energy consumed. The costs of energy for the maintenance treatments ranged from $174/lane-km for fog seal to $5,488/lane-km of the ultra thin overlay. The cold in-place recycling and mill and fill rehabilitation treatments had energy costs of $13,545 and $21,440/lane-km respectively. The costs of the energy consumed for the reconstruction treatments ranged from $21,710/lane-km for full depth reclamation and $71,164/lane-km for remove and replace with virgin materials. Based on a review of the City of Saskatoon’s 2012 proposed treatment plan for its roadway network the cost of energy was estimated at $1,232,000 for work on 93 lane-km of roadway. The costs of GHG emissions were also determined based on the amount of CO2e generated and the value of one tonne of carbon on the voluntary carbon credit market at $6/tonne. The costs of carbon for the maintenance treatments ranged from $3/lane-km for fog seal to $64/lane-km for the ultra thin overlay. For the rehabilitation treatments the cost of carbon for the cold in-place recycling was $224/lane-km and $266/lane-km for the mill and fill treatment. The reconstruction treatments ranged from $524/lane-km for full depth reclamation and $1,062 for remove and replace with virgin materials. Finally four field case studies were reviewed to determine the amount of energy consumed and GHG emissions generated through construction. The first was the reconstruction of Range Road 232, a rural roadway with virgin materials. The second was the reconstruction of Kenderdine Road with recycled materials. The energy consumed and GHG emissions generated for these construction projects are 1,917 and 1,146 GJ/lane-km, and 150.3 and 92.6 t CO2e/lane-km, respectively. The third case study further reviewed the use of warm mix asphalt concrete (WMAC) and the use of recycled asphalt pavement (RAP) in the Kenderdine Road pavement structure. This research determined that with the incorporation of WMAC and 10 percent RAP in the asphalt layers and with the use of recycled materials in the base layers the amount of energy consumed would be reduced by 31.8 percent and the GHG emissions reduced by 34.8 percent compared to a traditional virgin pavement structure. The final case study reviewed the City of Saskatoon’s 2012 proposed roadway restoration and reconstruction plan. From the model it was found that 38,281 GJ of energy was consumed and 2,617 t CO2e was generated. This work shows that the probabilistic model developed in this research may be applied to a variety of roadway treatments from maintenance to reconstruction in urban and rural applications. With the use of the model, roadway project managers can make informed decisions for roadway treatments based on energy consumption and GHG emission generation values. By incorporating the amount of energy that is consumed and GHG emissions generated into the decision making process of roadway infrastructure management, more sustainable infrastructure management can be achieved.

The current manner of constructing roads with virgin aggregates is unsustainable for many urban centers as natural sources for quality aggregates are being or have been depleted. As well, there is little understanding or scientific data published as to the impacts on roadway design and life cycle performance with poorer quality aggregate material. To improve future sustainability of roadway utility, there is a need for better understanding of the mechanistic behavior of road aggregates and their respective role in road structural performance in the field. As well, there is a need to find more sustainable sources of quality aggregates to construct roadways. The goal of this research is to improve road utility sustainability through a better understanding of life cycle performance and incorporating field state mechanistic principles in the initial design of the roadway structure. The primary objective of this research was to investigate the application of recycle rubble materials using a mechanistic materials characterization and structural design process for urban roadways within typical City of Saskatoon roads and field state conditions. Specific technical objectives of this research were to characterize various recycled aggregate materials with regards to their road structural behavior as a high quality base coarse, quantify the cost comparison between various design cross sections, and evaluate the structural behavior of these alternate aggregate sources in typical structural designs and Saskatoon field state conditions. To validate the field behavior of recycled aggregates, various test sections were constructed with different recycled and virgin aggregate structural systems. These test sections were evaluated using non-destructive structural assessment to determine their structural quality in the field. This research studied the use of recycled portland cement concrete aggregates and recycled asphalt cement aggregates as structural granular layers of typical City of Saskatoon roadways. These materials were characterized using conventional and mechanistic lab characterization protocols. Field test sections were constructed to validate that recycled materials could be employed as quality replacements for virgin aggregates. Research was also conducted on how to incorporate mechanistic based materials testing and structural design into City of Saskatoon Design and Materials Selection Specifications and Processes. The resilient modulus of the various road materials was also compared to relate to other mechanistic-empirical design methodologies. The laboratory testing conducted in this research indicated that although conventional empirical testing shows recycled asphalt materials to be of lesser quality, when evaluated using mechanistic characterization protocols, recycled asphalt concrete material yielded superior structural behavior. To illustrate, the dynamic modulus of recycled asphalt concrete was 697 MPa under a fully reversed stress state and a frequency of 0.5 Hz compared to 264 MPa for a high quality conventional high fracture granular base under the same stress state and frequency. As well, the recycled asphalt material showed less moisture susceptibility than conventional granular aggregate. This research showed recycled portland cement concrete aggregate materials showed good drainage and capillary break qualities when tested against the standard granular base materials. Although the well graded recycled asphalt cement and well graded recycled portland cement concrete were shown to have slightly higher moisture intake values, the increased moisture did not increase the swell and therefore indicates adequate frost resistance due to moisture. This research showed conventional roadway design utilized by the City of Saskatoon does not have the means to evaluate recycled asphalt and portland cement aggregates from a materials selection and structural design perspective. Roadway designs using a mechanistic approach were able to accurately represent the field structural primary responses of test roadway structures considered in this study and were able to incorporated recycled aggregate in the design process. Designing roads using a mechanistic design process showed a significant improvement in roadway structural responses in designs using recycled aggregate material. From an economic perspective, this research showed road cross sections utilizing recycle aggregate materials proved to be the least expensive option when evaluated by the initial capital cost and the projected life cycle costing. When comparing primary structural responses to construction cost, up to 20 percent of costs to construct a road can be saved, and a properly designed road structure using recycled aggregates will reduce the strains in the structures by up to 90 percent. As well, using recycled aggregates to construct roadways will reduce the fuel consumption during construction by up to 20 percent due to a reduction in aggregate hauling distances. In summary, when evaluated with a mechanistic road structural design method that accounts for the material characteristics of various aggregates, recycled asphalt rubble processed as a black base and recycled portland cement concrete as a stress dissipating drainage layer within the construction of new roadways is a more sustainable approach to designing and constructing structurally sound roads than the conventional methods. Based on the findings of this research, proper stockpiling and recycling of asphalt and concrete rubble materials is recommended in the City of Saskatoon. In order to optimize and incorporate various recycled aggregate materials into road design it is recommended the City of Saskatoon employ mechanistic based road material characterization and structural design.

The purpose of the study was to explore the potential of resident employed photography as a context sensitive assessment tool in roadway design by identifying the key elements of resident employed photography and context sensitivity and then exploring the potential of the elements of resident employed photography that may contribute to context sensitivity in roadway design. State and federal transportation agencies have identified principles and potential outcomes with the intent to guide processes that are sensitive to the context of a project’s surroundings. The improved design of public roadways to meet the needs of those who live and travel along them is the goal of these agencies. Resident employed photography is the use of a photograph to obtain information from a participant. The study explored resident employed photography as a context sensitive technique in the discovery of the attributes that reflect and define participant attachment to an environment. The technique therefore relied upon the existing community in the establishment of elements of value to be used to shape and guide the roadway design of the realignment of Utah State Route 30 through a neighborhood in Logan, Utah. Cameras and photograph logs were distributed to households in the residential area and participants were invited to provide contextual information about their neighborhood with regard to the proposed realignment. This information was gathered and analyzed using a grounded theory approach. The data derived from the participant’s photos, written comments, and interviews shaped and added to the research questions and resultant theory. In the study, areas of concern and mitigation ideas as identified by the participants found that a complete streets approach focused on maintaining or improving the feel of the neighborhood may be the best possible alternative in the realignment of SR-30. However, the success of this alternative is largely dependent upon a design professional’s consideration of the contextual relevance of the data provided through resident employed photography.

Orientador: Eliseu Savério Sposito / Resumo: A competitividade atinente ao capitalismo, torna-se mais imperativa com o aumento, nas últimas décadas, da fluidez obtida principalmente depois da Segunda Guerra Mundial. Atualmente, além de todo aparato tecnológico, concretizado no intenso uso das tecnologias da informação e das comunicações, a consecução da fluidez é possível através da logística industrial, e conseqüentemente, da formação de redes cada vez mais complexas e dinâmicas, em arranjos paradoxais de competitividade e cooperação. Em relação à logística industrial, sua atividade principal é o transporte, que no Brasil se corporifica, na sua maior parte, no transporte rodoviário de cargas. A melhor interpretação de toda essa dinâmica foi possível através da sistematização do estudo sobre o transporte rodoviário de cargas, sua logística e suas redes, em três cidades médias do interior paulista, que neste caso foram Presidente Prudente, São José do Rio Preto e Bauru. / Abstract: The competitiveness intrinsical to the capitalism becomes more imperative with the increase, in the last decades, of the fluidity gotten mainly after the Second World War. Currently, beyond all technological apparatus, materialize in the intense use of the technologies of the information and the communications, the achievement of the fluidity is possible through the logistic industrial, and consequently, of the formation of more complexes and dynamics networks each time, in paradoxical arrangements of competitiveness and cooperation. Regarding the logistic industrial, its main activity is the transport, that is materialized in Brazil, in its biggest part, in the roadway transportation of goods. The best interpretation of all this dynamics was possible through the systematization of the study about the roadway transportation of goods, its logistic one and its networks, in three average cities of State of São Paulo (Presidente Prudente, São José do Rio Preto e Bauru). / Mestre

Intelligent cruise control (ICC) has the potential to impact both roadway throughput and safety by assisting drivers in maintaining safe headways. This thesis explores this potential through comparisons of ICC to conventional cruise control (CCC) and manual driving. Accordingly, descriptions are given of both CCC and ICC systems. Furthermore, descriptions of ICC evaluation studies and car-following models are presented. The evaluation of ICC is conducted using data collected as part of the Field Operational Test (FOT) performed in Ann Arbor, Michigan. Two levels of analysis are presented in this thesis. The first level of analysis compares the usage of ICC to CCC from a macro level. This study demonstrated that ICC was used more along similar trips. In addition, it was shown that there was no difference in usage of the ON, SET, CANCEL and RESUME buttons. ICC resulted in a higher usage of the ACCEL button and a lower usage of the COAST button compared to CCC. Furthermore, the number of brake interventions while ICC was engaged was higher than CCC. Lastly, the macro-level analysis indicated that there was no difference in the number of near encounters for ICC and CCC. The second analysis makes comparisons at a micro level. The most probable speed, acceleration and headway for each driving mode as well as the probability of using cruise control (based on speed) were determined. The probability of ICC use exceeded CCC use for every freeway speed bin and all but two high-speed arterial speed bins. Finally, a car-following behavior comparison was performed. Manual driving resulted in larger headway values for speeds less than 80 km/h. The ICC speed-headway curve was similar to the CCC speed-headway curve created from high-speed arterial data. The mean headway-speed charts, however, indicated that ICC was more similar to manual driving. Exploration into the specific differences is needed in order to determine the impact of ICC on system safety. / Master of Science

The limited available budget along with old aging infrastructure in nation magnifies the role of strategic decision making for maintenance of infrastructure. The challenging objective is to maintain the infrastructure asset systems in a state of good repair and to improve the efficiency and performance of the infrastructure systems while protecting and enhancing the natural environment. Decision makers are in need of a decision support system to consider these multiple objectives and criteria to effectively allocate funding and achieve the highest possible return on investment on their infrastructure. The research proposes and validates a framework for such decisions. The proposed model aims at finding optimal techniques for maintenance of multiple roadway asset items while taking into account time, cost, level of service and environmental impacts. Therefore, the goal is to answer what are the optimal combinations of maintenance techniques for roadway assets while more than one objective is being optimized. In other words, the main objective is to develop a decision support system for selecting and prioritizing necessary actions for MRandR (Maintenance, Repair and Rehabilitation) of multiple asset items in order for a roadway to function within an acceptable level of service, budget, and time while considering environmental impacts. To achieve these desirable outcomes, this model creates a two-stage framework for a sustainable infrastructure asset management. First a multi-objective problem based on the multi colony ant colony optimization is analyzed. The objectives of the problem are: (i) Minimizing maintenance costs, (ii) Minimizing maintenance time, (iii) Minimizing environmental impacts and (iv) Maximizing level of service improvement. In the second stage, the results of the multi objective optimization will be prioritized using a Multi Criteria Decision Making (MCDM) process. The proposed approach will simultaneously optimize four conflicting objectives along with using a multi criteria decision-making technique for ranking the resulted non-dominated solutions of multi objective optimization. The results of implementation of the proposed model on a section of I-64 highway are presented for a sub-set of asset items. Moreover, the proposed model is validated using a scalable test problem as well as comparison with existing examples. Results reveal the capability of the model in generation of optimal solutions for the selection of maintenance strategies. The model optimizes decision making process and benefits decision makers by providing them with solutions for infrastructure asset management while meeting national goals towards sustainability and performance-based approach. In addition, provides a tool to run sensitivity analysis to evaluate annual budget effects and environmental impacts of different resource allocation scenarios. Application of the proposed approach is implemented on roadway asset items but it is not limited to roadways and is applicable to other infrastructure assets. / Ph. D.