In this thesis I provide general guidelines for a commercial building owner’s decision making process for heating, ventilation, and air-conditioning (HVAC) system energy efficiency projects, discuss an example HVAC project at an existing building, and recommend the most energy-efficient, cost-effective project option. First, a building’s HVAC system’s inefficiencies are identified. The systems and the components can be investigated to understand the nature of the operations. In the building owner’s interests, possible alternatives can be developed to address the systems with improvements. Consulting engineers, contractors, and other building professionals can assist in this process. There are necessary engineering and construction considerations for defining realistic project alternatives. With the alternatives, there are costs, benefits, and trade-offs. The costs, which mainly include the investment and the operational costs, and the benefits, which mainly include the available financial incentives, defined in dollars, are identified for the alternatives. The alternatives can be evaluated with Building Life Cycle Cost (BLCC) software. In this evaluation the net present-value (NPV) method is used to rank the alternatives. Then, the highest-ranking, lowest life-cycle cost, alternative is recommended for the owner. In the example, an existing commercial building’s HVAC systems are considered. The construction plans, the facilities records, and the existing field conditions were investigated and analyzed. A few operational inefficiencies were identified. To address two of these existing inefficiencies, there were alternatives considered to replace the standard-efficiency air handling unit motors with premium-efficiency motors and to renovate the ventilation system with an energy recovery wheel. The investment costs, the available rebates, the net annual energy savings, and the energy and other operational costs were estimated, over a 30-year study period, for each of these alternatives, and compared to the costs of the existing system. The BLCC evaluations were performed across a range of discount rates in the present-value calculations. Based on the lowest present-value life-cycle cost reports, the premium-efficiency motor replacement project only is recommended. / text

Pavements encompass a significant component of the total civil infrastructure investment. In Ontario, the Ministry of Transportation (MTO) is responsible for the maintenance and construction of approximately 39,000 lane-kilometres of highway. In 2004, the province estimated the value of the total highway system at $39 billion dollars. Thus, managing this asset is an important factor to ensure a high level of service to the traveling public. One of the most important indicators of level of service for a road network is safety. Each year, thousands of motorists across North America are involved in motor vehicle collisions, which result in property damage, congestion, delays, injuries and fatalities. The MTO estimated that in 2002, vehicle collisions in Ontario cost nearly $11 billion. Despite the importance of highway safety, it is usually not considered explicitly in the pavement management framework or maintenance analysis. A number of agencies across North America collect skid data to assess the level of safety at both the project and network level (Li et al, 2004). However, a number of transportation agencies still do not collect friction data as part of their regular pavement data collection programs. This is related to both liability concerns and lack of knowledge for how this data can be effectively used to improve safety. The transportation industry generally relies on information such as collision rates, black-spot locations and radius of curvature to evaluate the level of safety of an alignment (Lamm et al., 1999). These are important factors, but the use of complementary skid data in an organized proactive manner would also be beneficial. In preparation for a considered Long Term Area Maintenance Contract, a project was initiated by the MTO to collect network level friction data across three regions in the Province of Ontario. This project represents the first time friction data was collected at the network level in Ontario. In 2006, approximately 1,800 km of the MTO highway network was surveyed as a part of this study. This research utilized the network level skid data along with collision data to examine the relationships and model the impacts of skid resistance on the level of safety. Despite the value of collecting network level skid data, many Canadian transportation agencies still do not collect network level skid data due to the costs and potential liability associated with the collected data. The safety of highway networks are usually assessed using various levels of service indicators such as Wet-to-Dry accident ratio (W/D), surface friction (SN), or the collision rate (CR). This research focused on developing a framework for assessing the level of safety of a highway network in terms of the risk of collision based on pavement surface friction. The developed safety framework can be used by transportation agencies (federal, state, provincial, municipal, etc.) or the private sector to evaluate the safety of their highway networks and to determine the risk or probability of a collision occurring given the level of friction along the pavement section of interest. As a part of the analysis, a number of factors such as Region, Season of the Year, Environmental Conditions, Road Surface Condition, Collision Severity, Visibility and Roadway Location were all investigated. Statistical analysis and modeling were performed to developed relationships which could relate the total number of collisions or the collision rate (CR) to the level of available pavement friction on a highway section. These models were developed using over 1,200 collisions and skid test results from two Regions in the Province of Ontario. Another component of this study examined the Wet-to-Dry accident ratio and compared it to the Skid Number. A number of Transportation Agencies rely on the Wet-to-Dry accident ratio to identify potential locations with poor skid resistance. The results of the comparison further demonstrated the need and importance of collecting network level skid data. Another component of this study was to evaluate the effectiveness of various preservation treatments used within the Long Term Pavement Performance (LTPP) study. In addition, modeling was performed which examined the historical friction trends over time within various environment zones across North America to investigate skid resistance deterioration trends. The results of the analysis demonstrated that commonly used preservation treatments can increase skid resistance and improve safety. The cost effectiveness of implementing preservation and maintenance to increase the level of safety of a highway using Life Cycle Cost Analysis (LCCA) was evaluated. A Decision Making Framework was developed which included the formulation of a Decision Matrix that can be used to assist in selecting a preservation treatment for a given condition. The results of this analysis demonstrate the savings generated by reducing the number of collisions as a result of increasing skid resistance. The results of this research study have demonstrated the importance of network level friction testing and the impact of skid resistance on the level of safety of a highway. A review of the literature did not reveal any protocol or procedures for sampling or minimum test interval requirements for network level skid testing using a locked-wheel tester. Network level friction testing can be characterized as expensive and time-consuming due to the complexity of the test. As a result, any reduction in the required number of test points is a benefit to the transportation agency, private sector (consultants and contractors) and most importantly, the public. An analysis approach was developed and tested that can be used to minimize the number of required test locations along a highway segment using common statistical techniques.

During the evaluation of the seismic retrofitting option for risk reduction/mitigation measures to be applied over buildings, Benefit Cost Analysis is an often-used method. During this study of Benefit Cost Analysis, the condition that the earthquake can happen just after or sometime after retrofitting will be taken into consideration rather than some approaches that focus on the benefits and costs regarding the annual probability of the occurrence for possible earthquakes. The analysis will use conditional probability such that the earthquake will be assumed to occur at different periods of time (5, 10, 20 years etc.) after the mitigation measures are taken so that benefit-cost ratios and net social benefits can be observed over time using the results at these periods. Also during this study the indirect effects of earthquake such as business disruption, social disturbance will also be taken into consideration. As a final step, it is aimed to conclude with convincing financial results regarding the direct and indirect effects of the earthquake in terms of benefits and costs to encourage people and the public officials to reduce the potential vulnerability of the housing units people live by taking the necessary precautions against the earthquake.

An office building (sthlm new hus 4) located in the south of Hammarbyhamnen overlooking Hammarbybacken is planned in 2018. Climate control of the office building are via radiators, high-temperature chilled beam and pre-treated supply air. The building is currently being designed for district heating and remote cooling. The study aims to investigate whether borehole thermal energy system (BTES) are a reasonable alternative to provide the office building with heat and cooling, from an environmental- and life cycle cost (LCC) perspective. The aim of the study is to generate an energy requirement for the office building, which is done by construct a model of the building using IDA ICE, a simulation software. The energy requirement is covered by either district heating/-cooling (energy system I) or BTES (energy system II) as the primary energy source. A model of the BTES is constructed in excel based on data from experience input. Life cycle cost analysis are used for economical comparison between the energy systems. The environmental assessment is based on Nordic electricity mix, which controls the impact of the energy systems. Energy system II entails a need for energy support to avoid over dimension the heat pump, which is done by complementing the surplus need through district heating and remote cooling. LCC shows an economic breakpoint at 11-year calculation period, where BTES becomes economically advantageously. Environmentally, energy system II releases 14.3 tonnes of CO2eq compared to energy system II which results in a reduced emission of 47 tonnes of CO2eq based on Nordic electricity mix.

abstract: The major challenge for any pavement is the freight transport carried by the structure. This challenge is expected to increase in the coming years as freight movements are projected to grow and because these movements account for most of the load related distresses for the pavement. Substantial effort has been devoted to identifying the impacts of these future national freight trends with respect to the environment, economic growth, congestion, and reliability. These are all important aspects relating to the freight question, but an equally important and often overlooked aspect of this issue involves the impact of freight trends on the physical infrastructure. This study analyzes the impact of future freight traffic trends on 26 major interstates representing 68% of the total system mileage and carrying 80% of the total national roadway freight. The pavement segments were analyzed using the Mechanistic Empirical Pavement Design Guide software after collecting the relevant traffic, climate, structural, and material properties. Comparisons were drawn between the expected pavement performance using current design standards for traffic growth and performance predictions that incorporated more detailed freight projections which themselves considered job growth and six key drivers of freight movement. The differences in the resultant performance were used to generate maps that provide a bird’s eye view of locations that are especially vulnerable to future trends in freight movement. The analysis shows that the areas of greatest vulnerability include segments that are directly linked to the busiest ports, and surprisingly those from Atlantic and Central states that provide long distance connectivity, but do not currently carry the highest traffic volumes. / Dissertation/Thesis / Masters Thesis Civil and Environmental Engineering 2016

Uma nova abordagem de sistema de gerência de pavimentos ferroviários é exposta nesta tese. O objetivo principal da pesquisa foi o desenvolvimento de um sistema de gerência em nível de rede e análises do custo do ciclo de vida em nível de projeto, adotando como estudo de caso a Estrada de Ferro Vitória Minas. A revisão bibliográfica apresenta modelos de avaliação da qualidade geométrica e estrutural no Brasil e no mundo. O desenvolvimento iniciou-se com a composição do sistema de gerência em nível de rede utilizando um inventário do trecho em estudo, a subdivisão dessa via em segmentos homogêneos de comprimento variável de acordo com a geometria (curva e tangente), e a aplicação de seis códigos: (i) classe de via; (ii) inventário da estrutura do pavimento com base no tipo de dormente; (iii) geometria com a definição da metodologia de avaliação da qualidade geométrica, propondo um índice que aplica o desvio padrão dos parâmetros geométricos (bitola, empeno, alinhamento e nivelamento transversal), a contagem de exceções e os respectivos limites de alerta, intervenção e segurança; (iv) superfície pela análise do desgaste do trilho e defeitos superficiais; (v) segurança pelo coeficiente de atrito; e (vi) capacidade estrutural com a aplicação do módulo de via parametrizado pelo carro controle. A partir dos seis códigos, foi possível categorizar a estratégia de manutenção aplicável e, em nível de projeto, foram analisadas as degradações do lastro e do desgaste do trilho, com definições de equações de predição, o que permitiu simular o custo do ciclo de vida das estratégias. Por fim, para verificar a viabilidade técnica da estratégia de manutenção apontada, foram estudadas as tensões no topo do lastro e do subleito e ainda o módulo de via por retro análise das deflexões medidas da via permanente em duas seções da EFVM. / A new approach to the railroad track management system is presented in this thesis. The main objective of the research was the development of a network management system and life cycle cost analysis in a project level, adopting as a case study of the Estrada de Ferro Vitoria Minas. The bibliographic review has exposed geometric and structural track quality evaluation models in Brazil and in the world. The development began with the composition of the network management system using an inventory of the track under study, the subdivision of the railway into homogeneous segments of variable lengths depending on the geometry (curve and tangent), and the application of six codes: (i) class, (ii) pavement structure inventory based on tie type, (iii) geometry with definition of quality assessment methodology proposing an index that applies the exception counting and the standard deviation of the parameters - cross level, warp, alignment and gauge - and safety, alarm and intervention limits, (iv) surface by analysis of rail wear and rail surface defects, (v) safety by friction coefficient, and (vi) structural capacity with the application of the track modulus parameterized by the track geometry car. From the six codes, it was possible to categorize the applicable maintenance strategy at a project level, create prediction equations of the ballast and the rail wear degradation and simulate life cycle cost of the strategies. In order to verify the technical feasibility of the mentioned maintenance strategy, it was measured the stress at the top of the ballast and subgrade and the track modulus by retroanalysis deflections in two sections of the EFVM.

Orientador: Cassio Eduardo Lima de Paiva / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-08T04:23:34Z (GMT). No. of bitstreams: 1 RodriguesFilho_Silvio_M.pdf: 3429729 bytes, checksum: 7f6d53cce70fa58663e34d8677056eac (MD5) Previous issue date: 2006 / Resumo: Este estudo identifica o ponto de equilíbrio econômico entre o uso de um Pavimento Flexível ou Rígido em função do nível de tráfego e capacidade de suporte de subleito, relacionado a custo/m2 e taxa de amortização através do dimensionamento do Pavimento Flexível pelo método CBR e do pavimento rígido pelo método da PCA/66. Considera cenários de intervenções nesses pavimentos ao longo de um ciclo de vida de 10 e 40 anos onde os materiais são variados, referenciando as estruturas de pavimento a um mesmo patamar monetário e temporal, através da variável dependente Valor Presente Líquido (VPL). Mostra que quaisquer que sejam os procedimentos de dimensionamento que venham a definir o tipo de estrutura de pavimento a ser adotado em um empreendimento rodoviário, esses devem ser acompanhados de uma análise econômica utilizando-se do conceito de ¿Life Cycle Cost Analysis (LCCA)¿. Como conclusão, é mostrado que deve ser evitado a opção por um tipo de estrutura de pavimento que envolve custo inicial e os custos de intervenções, baseado apenas em seu custo inicial. A simples análise de custo inicial pode não ser a melhor opção ao longo do ciclo de vida de um pavimento sob o ponto de vista do investidor, em função do custo do dinheiro disponível no mercado / Abstract: This study identify the break-even-point between Rigid and Flexible pavement use function of the traffic and subgrade support related to cost/m2 and discount rate, through CBR method of Flexible Pavement Design and PCA/66 Rigid pavement design. Consider intervention scenarios of 10 and 40 years with materials variations referred to the pavement structures of the same monetary and temporal landing through dependent variable Net Present Value (NPV). Show that wherever be the design pavement procedures to define the pavement structure in a roadway enterprise is mandatory to come with an economic analysis using the Life Cycle Cost Analysis (LCCA) conceptions. As a conclusion is showed to be mandatory to avoid option for a pavement structure that involves initial and interventions costs, based only on its initial costs. The simple initial cost analysis couldn¿t be best option over the investor point of view considering the money cost available in the market / Mestrado / Transportes / Mestre em Engenharia Civil

Energy and cost performance optimization for commercial building system design is growing in popularity, but it is often criticized for its time consuming process. Moreover, the current process lacks integration, which not only affects time performance, but also investors’ confidence in the predicted performance of the generated design. Such barriers keep building owners and design teams from embracing life cycle cost consideration. This thesis proposes a computationally efficient design optimization platform to improve the time performance and to streamline the workflow in an integrated multi-objective building system design optimization process. First, building system cost estimation is typically completed through a building information model based quantity take-off process, which does not provide sufficient design decision support features in the design process. To remedy this issue, an automatic cost estimation framework that integrates EnergyPlus with an external database to perform building systems’ capital and operation costs is proposed. Optimization, typically used for building system design selection, requires a large amount of computational time. The optimization process evaluates building envelope, electrical and HVAC systems in an integrated system not only to explore the cost-saving potential from a single high performance system, but also the interrelated effects among different systems. An innovative optimization strategy that integrates machine learning techniques with a conventional evolutionary algorithm is proposed. This strategy can reduce run time and improve the quality of the solutions. Lastly, developing baseline energy models typically takes days or weeks depending on the scale of the design. An automated system for generating baseline energy model according to ANSI/ASHRAE/IESNA Standard 90.1 performance rating method is thus proposed to provide a quick appraisal of optimal designs in comparison with the baseline energy requirements. The main contribution of this thesis is the development of a new design optimization platform to expedite the conventional decision making process. The platform integrates three systems: (1) cost estimation, (2) optimization and (3) benchmark comparison for minimizing the first cost and energy operation costs. This allows designers to confidently select an optimal design with high performance building systems by making a comparison with the minimum energy baseline set by standards in the building industry. Two commercial buildings are selected as case studies to demonstrate the effectiveness of this platform. One building is the Center for Sustainable Landscapes in Pittsburgh, PA. This case study is used as a new construction project. With 54 million possible design solutions, the platform is able to identify optimal designs in four hours. Some of the design solutions not only save the operation costs by up to 23% compared to the ASHRAE baseline design, but also reduce the capital cost ranging from 5% to 23%. Also, compared with the ASHRAE baseline design, one design solution demonstrates that the high investment of a product, building integrative photovoltaic (BiPV) system, can be justified through the integrative design optimization approach by the lower operation costs (20%) as well as the lower capital cost (12%). The second building is the One Montgomery Plaza, a large office building in Norristown, PA. This case study focuses on using the platform for a retrofit project. The calibrated energy model requires one hour to complete the simulation. There are 4000 possible design solutions proposed and the platform is able to find the optimal design solution in around 50 hours. Similarly, the results indicate that up to 25% capital cost can be saved with $1.7 million less operation costs in 25 years, compare to the ASHRAE baseline design.

Water shortage, water contamination, and the emerging challenges in sustainable water resources management (e.g., the likely impacts of climate change and population growth) necessitate adopting a reverse logistics approach, which is the process of moving wastewater from its typical final destination back to the water supply chain for reuse purposes. This practice not only reduces the negative impacts of wastewater on the environment, but also provides an alternative to withdrawal from natural water resources, forming a closed-loop water supply chain. However, the design of such a supply chain requires an appropriate sustainability assessment, which simultaneously accounts for economic, environmental, and social dimensions. The overall aim of this work was therefore to contribute to the literature by evaluating the impacts of water reclamation and reuse according to the triple-bottom-line sustainability indicators (i.e., economic, environmental, and social) and to develop frameworks and mathematical models to help decision-makers, stakeholders, and officials with the design of sustainable water reclamation and reuse systems. The applicability of the developed frameworks and models was examined using real case studies and hypothetical scenario analyses. This enactment also revealed the tradeoffs and thresholds associated with the design of sustainable water reclamation and reuse systems. To conquer the mentioned goal, the research was conducted in three major sections. The first part of the research was outlined to design possible scenarios for water reuse based on water reuse guidelines and evaluate the different types of end-use based on the three major dimensions of sustainability (i.e., economic, environmental and social aspects), simultaneously. The different reuse types considered include unrestricted urban reuse, agricultural reuse, indirect potable reuse (IPR), direct potable reuse (DPR), distributed unrestricted urban reuse, as well as some degree of decentralization of treatment plants for distributed unrestricted urban reuse. The tradeoff investigation and decision-making framework were demonstrated in a case study and a regret-based model was adopted as the support tool for multi-criteria decision-making. This study revealed that although increasing the degree of treatment for water reuse required implementation of advanced treatment options and it increased the implementation, operation, and maintenance (O&M) costs of the design, it increased the value of resource recovery significantly, such that it can offset the capital and O&M costs associated with the treatment and distribution for DPR. Improving the reclaimed water quality also reduced the environmental footprint (eutrophication) to almost 50% for DPR compared to the other reuse scenarios. This study revealed that the distance between the water reclamation facility and the end use plays a significant role in economic and environmental (carbon footprint) indicators. In the second part of this research, a multi-objective optimization model was developed to minimize the costs and environmental footprint (greenhouse gas emissions), and maximize social benefits (value of resource recovery) of the water reclamation systems by locating the treatment facility, allocating treatment capacity, selecting treatment technology, and allocating customers (final reclaimed water users). The expansion of the water reclamation system in Hillsborough County, Florida was evaluated to illustrate the use of the model. The impacts of population density and topography (elevation variation) of the water service area on the model outputs were also investigated. Although the centralization of treatment facilities takes advantage of the economies of scale, the results revealed that simultaneous consideration of economic and environmental indicators favored decentralization of treatment facilities in the study area. This was mainly due to the significant decrease in water transfer requirements, especially in less populous areas. Moreover, the results revealed that contribution of population density to the optimal degree of decentralization of treatment facilities was significant. In the last part of this work, hypothetical scenarios for a water service area were generated to evaluate the impacts of external variables on the design of water reclamation and reuse systems. Although the conducted sensitivity analyses in the previous sections revealed the tradeoffs and thresholds associated with the design of water reclamation systems, the concept of a hypothetical study helped with the elimination of case-specific factors and local conditions that could possibly influenced the outcomes. These factors, which were specific to the case studies (e.g., the location of candidate sites for implementation of water reclamation facilities and special population distribution patters) made barriers to the conclusions and hurdled the interpretation of findings. Two major factors, which were found to be significant among the factors influencing the design of water systems (i.e., elevation variation and population density), were selected for the evaluation. Accordingly, three different topographies (i.e., flat region, medium elevation variation, and hilly) and three types of population density (i.e., low, medium, and high) were considered for the design of hypothetical cases and the previous model developed in the second section was modified and used to evaluate the impacts. The results revealed that although decentralization of water reclamation facilities decreases the costs and environmental impacts associated with water transfer phase (i.e., wastewater collection and reclaimed water distribution), there were tradeoffs between the impacts of decentralization of treatment plants and the benefits from economies of scale for treatment. The results showed that when the population density is high and there is moderate to high elevation variations in the water service area, decentralization of treatment facilities is the beneficiary option. However, if the population density is low, economies of scale for treatment becomes more influential and lower degrees of decentralization of treatment facilities is preferred.

In the last 40 years an increase in train speed and axle load around the world and other challenges in the conventional ballasted track system gave birth to ballastless railway track system. This study examines in depth the various slab track systems that are being used today. Their design characteristics as well as the various requirements for efficient use are thoroughly explained. At least 34 different ballastless systems have been recorded in many railway networks throughout the world. The most significant slab track systems are analysed in detail and compared. Slab track designs have significant advantages comparing to ballasted tracks. The most significant are the high stability of the track, the almost non-existent need for maintenance, the long life cycle (60 years) and the reduced weight and height of the track. Their disadvantages against the ballasted tracks are mainly summarized in their higher construction costs. The Finite Element package ABAQUS/CAE is used to model a 3-D slab track design under static traffic loading. The results suggest that slab tracks have profoundly better stability and durability comparing to ballasted tracks mainly due to their higher stiffness and strength. The author underlines the need for further studies to undoubtedly prove the claimed advantages of slab track systems as well as to improve the costs associated with construction.