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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

High-Intensity Discharge Industrial Lighting Design Strategies for the Minimization of Energy Usage and Life-Cycle Cost

Flory, Isaac L. IV 13 October 2008 (has links)
Worldwide, the electrical energy consumed by artificial lighting is second only to the amount consumed by electric machinery. Of the energy usage attributed to lighting in North America, approximately fifteen percent is consumed by those lighting products that are classified as High-Intensity Discharge (HID). These lighting products, which are dominated by Metal-Halide and High-Pressure Sodium technologies, range in power levels from 35 to 2000 watts and are used in both indoor and outdoor lighting applications, one category of which is the illumination of industrial facilities. This dissertation reviews HID industrial lighting design techniques and presents two luminaire layout algorithms which were developed to provide acceptable lighting performance based upon the minimum number of required luminaires as determined by the lumen method, regardless of the aspect ratio of the target area. Through the development of lighting design software tools based upon the Zonal Cavity Method and these layout algorithms, models for the quantification of energy requirements, lighting project life-cycle costs, and environmental impacts associated with conventional industrial lighting installations are presented. The software tools, which were created to perform indoor HID lighting designs for the often encountered application of illuminating general rectangular areas with non-sloped ceilings utilizing either High-Bay or Low-Bay luminaires, provide projections of minimal lighting system costs, energy consumption, and environmental impact based upon lamp selection, ballast selection, luminaire selection and lighting system maintenance practices. Based upon several industrial lighting application scenarios, lighting designs are presented using both the new software tools and a commercially available lighting design software package. For the purpose of validating this research, analyses of both designs for each scenario are presented complete with results of illuminance simulations performed using the commercially available software. / Ph. D.
52

Economic Performance Assessment of Three Renovated Multi-Family Houses with Different HVAC Systems

Khadra, Alaa January 2018 (has links)
Since the building sector is responsible for 40% of the energy consumption and 36% of CO2 emissions in the EU, the reduction of energy use has become a priority in this sector. The EU has adopted several policies to improve energy efficiency. One of these policies aims to achieve energy efficient renovations in at least 3% of buildings owned and occupied by governments annually. In Sweden, a large part of existing buildings was built between 1965 and 1974, a period commonly referred to as ‘miljonprogrammet’. Stora Tunabyggen AB, the public housing company in Borlänge municipality, begun a renovation project in the Tjärna Ängar neighborhood within the municipality with the greatest share of its buildings stock from this period. The pilot project started in 2015. The aim of this project was to renovate three buildings with similar measures, that is, by adding 150 mm attic insulation, replacing windows with higher performing ones (U-value 1 W/m ²K), by adding 50 mm of insulation to the infill walls and by the installation of flowreducing taps. The essential difference between the three renovation packages is the HVAC systems. The selected HVAC systems are (1) exhaust air heat pump, (2) mechanical ventilation with heat recovery and (3) exhaust ventilation. Life cycle cost analysis was conducted for the three building and sensitivity analysis for different values of discount rate and energy price escalation was performed. The study found that the house with exhaust ventilation has the lowest life cycle cost and the highest energy cost. The house with exhaust air heat pump has 3% higher life cycle cost and 18% lower energy use at 3% discount rate and 3% energy price escalation. The study found that mechanical ventilation with heat recovery is not profitable, although it saves energy. The sensitivity analysis has shown that the possible increment of price energy and lower discount rate give higher value for the future costs in life cycle cost analysis. This lead to the main finding of this thesis, which is that exhaust air heat pump is the best choice for the owner according to the available data and the assessed parameters.
53

LIFE-CYCLE COST ANALYSIS OF REINFORCED CONCRETE BRIDGES REHABILITATED WITH CFRP

Smith, Jeffrey L. 01 January 2015 (has links)
The deterioration of highway bridges and structures and the cost of repairing, rehabilitating, or replacing deteriorated structures is a major issue for bridge owners. An aging infrastructure as well as the need to upgrade structural capacity for heavier trucks adds to problem. Life-cycle cost analysis (LCCA) is a useful tool for determining when the deployment of fiber-reinforced polymer (FRP) composite components is an economically viable alternative for rehabilitating deteriorated concrete bridges. The use of LCCA in bridge design and rehabilitation has been limited. The use of LCCA for bridges on a project level basis has often been limited to the non-routine design of major bridges where the life-cycle cost model is customized. LCCA has historically been deterministic. The deterministic analysis uses discrete values for inputs and is fairly simple and easy to do. It does not give any indication of risk, i.e. the probability that the input values used in the analysis and the resulting life-cycle cost will actually occur. Probabilistic analysis accounts for uncertainty and variability in input variables. It requires more effort than a deterministic analysis because probability distribution functions are required, random sampling is used, and a large number of iterations of the life-cycle cost calculations are carried out. The data needed is often not available. The significance of this study lies in its identification of the parameters that had the most influence on life-cycle costs of concrete bridge and how those parameters interacted. The parameters are: (1) Time to construct the new bridge; (2) traffic volume under bridge (when applicable); (3) value of time for cars; and (4) delay time under the bridge during new bridge construction (when applicable). Using these parameters the analyst can now “simulate” a probabilistic analysis by using the deterministic approach and reducing the number of iterations. This study also extended the use of LCCA to bridge rehabilitations and to bridges with low traffic volumes. A large number of bridges in the United States have low traffic volumes. For the highway bridge considered in the parametric study, rehabilitation using FRP had a lower life-cycle cost when compared to the new bridge alternative.
54

An approach to multi-objective life cycle cost optimization of wind turbine tower structures

Horsthemke, Hagen Wolfgang 12 1900 (has links)
Thesis (MEng)-- Stellenbosch University, 2013. / ENGLISH ABSTRACT: Support tower structures of Wind Energy Conversion Systems (WECS) are major cost items and by means of integrated design and optimization, the Life-Cycle Cost (LCC) can be reduced substantially. In this thesis, Horizontal Axis Wind Turbine (HAWTs) tower structures are investigated by means of a technique or tool that can bene t in decision making related situations to reduce the LCC of such WECS support towers from inception to disposal. Often, during the conceptual design phase a certain level of uncertainty or fuzziness exists and plays a role. The central focus in this project is on lattice type towers; however an account on tapered, tubular monopole towers is given as well. The problem is identi ed to be of a multi-objective nature, where a variety of criteria or objectives that are identi ed play a role in the possible reduction of the total LCC of the structure. The study also entails the delineation and discussion of the factors and components that a ect the LCC of a steel structure. The decision maker has control over only a few of these factors and components as identi ed, and these can be formulated by means of an objective to be minimized (or maximized in several other cases). Some of the objectives are incommensurable and others are commensurable with each other. In other words, several of these objectives either `compete' or don't `compete' against each other, respectively. The investigation resulted in the development of a multi-objective LCC optimization using the λ-formulation (or min-max formulation) as the objective aggregating approach for the four objectives identi ed (varied during analysis for sensitivity checks). The objectives are user-de ned in terms of membership functions that grade the degree of membership from total acceptance to total rejection by means of boundary values. This formulation is Non-Pareto based and the decision maker obtains the best trade-o or best compromise solution. The detailed discussion around these objectives is included in the literature study. The objectives in the multi-objective study are weight, cost, perimeter and nodal deflections, and a weighting of the objectives is possible but this is excluded from this study. A Genetic Algorithm (GA), coded in MATLAB, is implemented as the optimization tool or technique. The algorithm uses a quadratic penalty function approach and a natively written Finite Element Analysis (FEA) tool is used for the response model in the tness evaluation process, where the performance for stability, capacity and overall deflections of an individual in the population is quanti ed. A GA has the advantage that it operates on an entire population of individuals using basic principles such as genetics, crossover, mutation, selection and survival of the ttest from biology and Darwinian principles. GAs are very robust and e ective global search methods that can be applied to most elds of study. GAs have previously been e ectively applied in structural, single objective optimization (structural weight) problems. The GA is adopted and modi ed and veri ed with results on academic problems obtained from literature. Satisfactory performance was observed, although room for improvement is identi ed. A case study on a full scale model is performed, using circular hollow sections and equal leg angle sections. These are commonly used steel profi les for lattice type towers. The results obtained are as expected. The structural mass was used as a measure to compare the results. A heavier structure is obtained using the equal leg angle sections compared to the CHS structure with a di fference of up to 20% in weight. The best compromise solutions are feasible and near optimal, given the conditions of the equally weighted objectives in this study. The membership function defi nition and boundary value determination still remains a key issue when using fuzzy logic to incorporate the preference information of the decision maker. / AFRIKAANSE OPSOMMING: Toringstrukture van windturbines is belangrike kostekomponente van `n windkragopwekking stelsel. Deur middel van geï ntegreerde ontwerp en optimalisering kan die lewensikluskoste aansienlik verminder word. In hierdie tesis word horisontale-as windturbinetoringstrukture ondersoek. Deur middel van `n tegniek of hulpmiddel wat kan baat vind by besluitneming situasies, word die lewensiklus-koste van sodanige windturbine ondersteuning torings vanaf voorgebruik-fase tot lewenseinde-fase verminder. Dikwels, tydens die konseptuele ontwerp-fase, speel `n sekere vlak van onsekerheid of verwarring ook `n rol. Die sentrale fokus in hierdie projek is op staal vakwerk tipe torings gelê. `n Vereenvoudigde ontleeding van buisvormige torings is ook benader. Die probleem is van multikriteria aard, waar `n verskeidenheid van kriterie of doelwitte ge denti seer was. Hulle speel `n rol in die moontlike vermindering van die totale lewensiklus-koste van die struktuur. Die studie behels ook die bespreking en afbakening van die faktore en komponente wat die lewensiklus-koste van 'n staal struktuur bepaal. Die besluitnemer het slegs beheer oor sekere van hierdie faktore en komponente, en hierdie word deur middel van `n saamgevoegde doel-funksie gede neer wat dan geminimeer word. Sommige van die doelfunksies kompeteer met mekaar en sommige kompeteer nie met mekaar nie. Die ondersoek het gelei tot die ontwikkeling van `n multikriteria lewensiklus-koste optimalisering met behulp van die λ-formulering (of min-max formulering). Hierdie is `n tegniek wat die kriterie in vorm van `n verteenwoordigende doel-funksie saamvoeg. Daar is vier doelwitte wat geï denti seer was. Die gebruiker de nieer spesiale, lineêre doel-funksies wat van totale aanvaarding tot totale verwerping streek. Dit word deur middel van randwaardes gedoen. Hierdie formulering is nie Pareto gebaseer nie, en die besluitnemer verkry die `best trade-off ' of die beste kompromis oplossing. Die detailleerde bespreking rondom hierdie doelwitte is in die literatuurstudie ingesluit. Die doelwitte wat in die multikriteria studie gebruik word is gewig, koste, omtrek van die snitpro el en strukturêle defleksie. `n Gewig kan aan elke kriterium toegeken word, maar dit word van hierdie studie uitgesluit. `n Genetiese algoritme (GA), geï mplementeer in MATLAB, word as die optimalisering instrument en tegniek gebruik. Die algoritme gebruik `n kwadratiese `straf-funksie' en `n MATLAB Eindige Element Analise (EEA) word gebruik vir die gedragsmodel in die `fi ksheid' evalueringsproses. Die prestasie vir stabiliteit, kapasiteit en algehele verlegging van `n individu in die GA bevolking word daardeur gekwanti seer. `n GA het die voordeel, dat dit met `n hele bevolking van individue werk. Dit is gebaseer op beginsels van genetika en Darwin se beginsels. GAs is baie stabiel en ook e ektiewe globale soek metodes wat van toepassing in verskillende studierigtings is. GAs is al e ektief toegepas in strukturêle optimalisering (veral strukturêle gewig optimalisiering). Die GA in hierdie studie was aangepas en die gedrag en prestasie is bevestig met resultate van akademiese probleme uit die literatuur. Bevredigende prestasie is waargeneem, maar ruimte vir verbetering is ook geï denti seer. `n Gevallestudie oor `n grootskaal model is uitgevoer, en die gebruik van ronde holpro ele en gelykbenige hoekpro ele is uitgevoer. Dit is algemeen gebruikte staalpro ele vir vakwerk tipe torings. Die resultate wat verkry is, is soos verwag. Die strukturêle massa is gebruik as `n maatstaf om die resultate te vergelyk. `n Swaarder struktuur is die resultaat wanneer gelykbenige hoekpro ele gebruik word in vergelyking met die ronde holpro el struktuur. `n Verskil tot 20% in gewig is waargeneem. Die beste kompromis oplossing is haalbaar en naby-optimaal, gegewe die omstandighede van die gelyk geweegde doelfunksies in hierdie studie. Die doel-funksie de nisie, die voorkeur van die besluitnemer en die bepaling van die randwaardes bly steeds `n belangrike kwessie by die gebruik van hierdie benadering.
55

Framtida gasanvändning på Kalmar reningsverk : En ekonomisk jämförelse av olika investeringsmöjligheter

Halvorsen, Erik, Axelsson, Erik January 2017 (has links)
Då det finns planer på att ersätta det befintliga reningsverket i Kalmar inom en överskådlig framtid och nya krav om nödförsörjning av el har kommit från MSB, undersöktes möjligheten att använda den biogas som skulle komma att produceras på det nya reningsverket inom den egna verksamheten, istället för att som i dagsläget säljas. I denna studie undersöktes lönsamheten i att antigen investera i en biogasdriven generator som i normalfall ger en besparing i el och fjärrvärme och kan leverera reservkraft vid spänningsbortfall på nätet, eller försäljning av biogasen och inköp av ett dieseldrivet reservkraftverk.  Kostnadsförslag för biogasdrivna generatorer och reservkraftverk togs in. I denna ingick även service och komponenter för att kunna använda biogasen som bränsle. Utav kostnadsförslagen gjordes en LCC. Besparing av el och fjärrvärme samt förtjänst av försäljning av biogasen ställdes i relation mot varandra. Arbetet konkluderar att, baserat på de uträkningar som gjordes, en ottomotor är det mest lönsamma för att generera el och värme för internt bruk. / Because of the plans to replace the old sewage treatment plant in Kalmar, which has come to the end of its life cycle, and due to new requirements of emergency supply from SCCA (Swedish Civil Contingencies Agency), the possibility of using the biogas on the plant itself was evaluated. In this study, the profitability of two alternatives was evaluated. To invest in a biogas powered generator to produce electric power and heat, which would create savings in purchased electricity and district heating and work as an emergency generator, or to continue selling the biogas and invest in a diesel-powered emergency generator. Cost estimates of biogas powered generators and the equipment needed for using the biogas as fuel was required from dealers and manufacturers. The cost estimates were then compiled in a LCC. The calculated savings and the income from selling the biogas was then added to the LCC, the alternatives was then compared to each other. The study concludes that the most profitable alternative, based on the calculations, is to invest in a biogas powered generator and use the electricity and waste heat on the sewage plant.
56

Ackumulatorer som räddar liv : En livscykelkostnadsanalys om UPS som nödkraftkälla

Carlén, Camilla, Sandgathe, Ulrica January 2017 (has links)
Vid strömavbrott på fartyg krävs enligt SOLAS regelverk att en nödkraftkälla startar automatiskt. Världshandelsflottan använder sig idag till största delen av generatorer drivna av en fossildriven förbränningsmotor för detta. Här undersöktes möjligheten att istället använda sig av en UPS. Studien har fokuserat på frågan om det är möjligt enligt gällande regelverk, om det finns produkter på marknaden som uppfyller regelkraven samt hur kostnaderna för de två alternativen skiljer sig vad gäller inköp och underhåll i 25 år. Resultatet för kostnaderna redovisades i en livscykelkostnadskalkyl. Sett till regelverk ifrån Transportstyrelsens författningssamling samt klassificeringssällskapet DNV-GL är det tillåtet att använda ackumulatorer eller generatorer.    För att ha möjlighet att undersöka frågeställningen genom kostnadsförslag, sammanställdes en teoretisk fartygsmodell med svensk flagg. De företag som kontaktades var svenska tillverkare. Resultatet av den LCC som gjordes visade att det idag är billigare att investera i en konventionell nödgenerator. / The SOLAS regulations for merchant vessels states that in the event of loss of power, a backup power supply will start automatically. This paper investigated the possibility to replace the widely-used generator driven by a fossil-fuel powered internal combustion engine, with a UPS. Focus of the investigation included regulations concerning the use of accumulators onboard, market product range fulfilling the legal requirements and price difference based on purchase price and maintenance costs for 25 years. The cost results where compared as a Life Cycle Cost calculation. Regulations by the Swedish transport agency and the Classification DNV-GL allow the use of emergency power from accumulators or generator.   For the possibility to investigate through cost estimations, a theoretical model of a merchant vessel with Swedish flag, was set up. All companies contacted were Swedish manufacturer. The results in the LCC show the situation of today and lets us know that the most cost efficient investment is the conventional emergency generator.
57

Models for Life Cycle Cost Estimation of Spare and Wear Parts for Urban Gondola Lift Systems : A Case Study

Borhidai, András January 2019 (has links)
Urban gondola lift systems are becoming a regular sight rather than a rarity throughout the globe. Authors attribute their increasing popularity to factors such as environmental sustainability, operational reliability and cost efficiency compared to other right-of-way transit solutions. Replacing conventional modes of transit with urban gondolas cannot however be achieved without tackling several operational challenges. As potential new operators often lack the human resources and knowledge base required to successfully man, operate and maintain systems, they turn to manufacturers for increased after-sale support. Companies of the Doppelmayr Garaventa Group, the world’s largest manufacturer of gondola lifts, responded to these demand patterns by offering complete operations & maintenance contracts which, among other services, include the delivery and installation of reserve components. Calculating the total cost of such components for the life cycle of a system however still proves to be demanding and requires new computational models to increase its efficiency. The applicative purpose of this paper was thus set to formulate a model that is capable of performing life cycle cost calculations for components of urban gondola lift systems, according to a set of criterion defined by industrial entities. Its research aim is accordingly to answer questions about how concurrent instruments are set up, what models does contemporary research regard as efficient in similar industries and whether these models are able to enhance life cycle cost calculation capability within the urban gondola lift market. These aims were achieved through an analysis of current company practices, followed by the formulation of two new model alternatives based on a review of contemporary scientific literature, and concluded by an iterative process wherein the two alternatives were compared to each other in terms of performance and then merged to combine the best performing features of each version. Through a second iteration, the merged model was then compared to current instruments and established as the superior choice, using industry criteria. The paper concludes by resolving the research questions it set out to answer and making further recommendations for the direction of future research and studies.
58

Evaluation of low-quality recycled concrete pavement aggregates for subgrade soil stabilization

Tavakol, Masoumeh January 1900 (has links)
Doctor of Philosophy / Department of Civil Engineering / Mustaque A. Hossain / Stacey E. Kulesza / Recycled concrete aggregate (RCA) is the byproduct of the demolition of concrete structures and pavements. An estimated 140 million tons of concrete waste is produced annually in the United States, most of which ends up in landfills. The use of RCA to replace quarried aggregates in paving projects is one way to utilize these materials and alleviate concerns regarding this increasing waste stream. RCA usage prevents waste concrete disposal into landfills, resulting in more sustainable use of mineral aggregate sources, and may further reduce costs associated with paving projects. However, the inferior physical properties of RCA, such as the presence of recycled mortar, complicate the incorporation of RCA into new concrete mixtures. State highway agencies such as the Kansas Department of Transportation are facing further issues with RCA from D-cracked pavements, raising the question if D-cracked aggregates should be used in paving operations. No known work has evaluated the effect of RCA from D-cracked pavements in subgrade soil stabilization. This study stabilized a low-plasticity clay in Kansas using RCA and three stabilizing materials (lime, Class C fly ash, and a combination of Portland cement and fly ash). Candidate mixtures with varying proportions of chemical stabilizers and D-cracked aggregates were evaluated using the standard Proctor, unconfined compressive strength, linear shrinkage, and California Bearing Ratio tests. Microstructure characteristics of selected mixtures were explored using scanning electron microscopy (SEM) and energy dispersive X-ray tests. Laboratory test results indicated that RCA, in conjunction with all cementitious materials except lime, improved clay strength, stiffness, and shrinkage properties. SEM results indicated that RCA caused a low void space and a dense arrangement of soil particles. RCA effectively improved evaluated mixture properties when an adequate soil-RCA bond was reached using chemical agents. The long-term performance of full-depth flexible pavements with stabilized mixtures as subgrade was assessed in the AASHTOWare Pavement ME Design (commonly known as MEPDG) software. The life-cycle cost of flexible pavements with stabilized mixtures was estimated for a 40-year design period. Economic analysis results indicated that RCA was cost effective only if it was used with a combination of fly ash and Portland cement.
59

Contribuição para análise do custo do ciclo de vida de um sistema de gerência de pavimento ferroviário. / Life cycle cost analysis contribution for a railroad track management system.

Ribeiro, Fernando Sgavioli 27 October 2017 (has links)
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.
60

Life-Cycle-Cost Analysis of using Low Impact Development Compared to Traditional Drainage Systems in Arizona: Using Value Engineering to Mitigate Urban Runoff

January 2019 (has links)
abstract: The rate of urbanization has been impacted by global economic growth. A strong economy results in more people moving to already crowded urban centers to take advantage of increased employment opportunities often resulting in sprawling of the urban area. More natural land resources are being exploited to accommodate these anthropogenic activities. Subsequently, numerous natural land resources such as green areas or porous soil, which are less flood-prone and more permeable are being converted into buildings, parking lots, roads and underground utilities that are less permeable to stormwater runoff from rain events. With the diminishing of the natural landscape that can drain stormwater during a rainfall event, urban underground drainage systems are being designed and built to tackle the excess runoff resulting from urbanization. However, the construction of a drainage system is expensive and usually involves massive land excavations and tremendous environmental disturbances. The option for constructing an underground drainage system is even more difficult in dense urban environments due to the complicated underground environments, creating a need for low footprint solutions. This need has led to emerging opportunities for low impact development (LID) methods or green infrastructures, which are viewed as an environmentally friendly alternative for dealing with stormwater runoff. LID mimics the pre-development environment to retain the stormwater runoff through infiltration, retention, detention and evaporation. Despite a significant amount of prior research having been conducted to analyze the performance of runoff volume reduction and peak flow decrement of various green infrastructures, little is known about the economic benefits of using LID practices. This dissertation fills the gap in the knowledge regarding the life-cycle-cost effectiveness of green infrastructure in current urban developments. This study’s two research objectives are: (1) Develop a life cycle cost calculation template to analyze the cost benefits of using LID compared to the traditional drainage system (2) Quantify the cost benefits based on the real-world construction projects A thorough literature review led to the data collection of the hydrological benefits of using LIDs in conjunction with overviewing three real-world construction projects to quantify the cost benefits of LIDs. / Dissertation/Thesis / Doctoral Dissertation Civil, Environmental and Sustainable Engineering 2019

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