Seismic designs of building structures are currently made based on the design criterion of life-safety and this requires that the structures do not collapse to compromise safety of people in the structure, but they can be designed to experience some damage. However, this design approach has allowed large economic losses primarily due to the damage to the nonstructural components at relatively moderate levels of seismic intensities. This led to a new thinking about design approach called performance-based design approach that satisfies the life-safety objective at the same time, reduces the economic loss to an acceptable level. The performance-based design approaches are multi-level design that addresses several different levels of structural performances under different levels of seismic intensities. In this study, we have investigated the use of energy dissipating damping devices to achieve the performance of a building structure in a desirable manner over all levels of seismic intensity. Since the initial motivation of performance-based design was reducing economic loss, the life-cycle cost-based optimization is considered in this study to obtain the optimal designs with different damping devices. For the optimal design, three types of devices are used in this study: fluid viscous dampers, solid visco-elastic dampers, and yielding metallic dampers. The combinations of two different types of dampers are also examined in this study. The genetic algorithm (GA) approach is adopted as an optimizer that searches for the optimal solution in an iterative manner. Numerical results from the application of the optimal design to the selected model building are presented to demonstrate the applicability of the developed approach and to estimate the effectiveness of the obtained optimal design with each device. It is shown in the results that the optimal design with each individual damping devices or the combination of two different types of damping devices are very effective in reducing the expected failure cost as well as the displacement response quantities and fragilities. The results also show that the optimal designs focus relatively more on reducing economic losses for the lower but more frequent excitation intensities as these intensities contribute most to the failure costs. / Ph. D.

This research presents a framework system dynamics (simulation) model that evaluates the effect of maintenance policies on system performance and life-cycle cost. The model highlights factors such as learning, aging and the technological upgrades that occur during the life-cycle of a system. The metrics used to measure the effectiveness of maintenance policies are the system life-cycle cost and cumulative breakdowns. In this research, a varying maintenance policy has been modeled using system dynamics methodology to determine the future performance of the system that is dependent upon its past performance when breakdowns occur randomly. The main objective of this modeling approach is to balance the cost of preventive maintenance actions with the opportunity losses due to system breakdowns. The approach used in this research primarily involves forecasting future breakdowns using an average of accumulated opportunity losses. This research effort was mainly aimed at developing a (framework) model to determine effective maintenance policy for a system and evaluating the effect on the life-cycle cost for various scenarios. This model could further form the basis of a decision support system for maintenance modeling. / Master of Science

A well-maintained bridge infrastructure is a fundamental necessity for a modern society that provides great value, but ensuring that it meets all the requirements sustainably and cost-effectively is challenging. Bridge investment and management decisions generally involve selection from multiple alternatives. All of the options may meet the functional demands, but their life-cycle cost (LCC), service life-span, user-cost, aesthetic merit and environmental impact may differ substantially. Thus, life-cycle analysis (LCCA, a widely used decision-support technique that enables comparison of the LCC of possible options), is essential. However, although LCCA has recognized potential for rationalizing bridge procurement and management decisions its use in this context is far from systematic and the integration of LCCA findings in decisions is often far from robust. Thus, the overall objective of the work underlying this thesis has been to contribute to the development of sustainable bridge infrastructures while optimizing use of taxpayers’ money, by robustly incorporating life-cycle considerations into bridge investment and management decision-making processes. The work has introduced a full scheme for applying LCCA throughout bridges’ entire life-cycle. Several practical case studies have been presented to illustrate how an agency could benefit from use of a bridge management system (BMS) to support decisions related to the management of existing bridges and procure new bridges. Further developments include a comprehensive approach incorporating a novel LCCA technique, “LCC Added-Value Analysis”, which enables procurement of the most cost-efficient bridge design through a fair design-build (D-B) tendering process. A further contribution is a novel, holistic approach designed to enable procurement of bridges with the maximal possible sustainability (life-cycle advantages) under D-B contracts. The approach combines LCC Added-Value analysis with other techniques that make bridges’ aesthetic merit and environmental impact commensurable using an adapted concept named the willingness-to-pay-extra (WTPE). The systematic analytical procedures and potential of LCCA to deliver major savings highlighted in this thesis clearly demonstrate both the feasibility and need to integrate LCCA into bridge procurement and management decisions. This need has been recognized by Trafikverket (the Swedish Transport Administration), which has implemented a software tool developed in the research (BaTMan-LCC) in its bridge and tunnel management system (BaTMan). This thesis introduces readers to the field, considers BaTMan and the bridge stock in Sweden, discusses the developments outlined above and obstacles hindering further implementation of LCCA, then presents proposals for further advances. / <p>QC 20131029</p>

At the Swedish Transport Administration two different maintenance strategies are practiced to keep cameras in road tunnels clean. The theory of Life Cycle Cost, LCC, is applied on maintenance depending on its Level of Automation, LoA, and is further developed. In the case of cameras, in Swedish road tunnels the processes demonstrate two different LoA. LCC is used to compare and analyze how the properties between semiautomatic and manual maintenance affect investment costs, operational costs and the cost of preventive and corrective maintenance. Semiautomatic cleaning maintenance of cameras in road tunnels indicate a larger LCC than manual maintenance. This is due to a larger investment cost for machinery, but a similar annual cost for preventive maintenance. The presented properties affecting LCC are placed in a general context. This emphasize the significance of examining costs at high level of detail and comprehend the properties causing the costs.

This report documents an MSc Thesis work of sub-transmission reliability study using PSS/Eperformed at Vattenfall. The network that is examined in this thesis is a sub-transmission network.Vattenfall Distribution Sweden is going to invest and rebuild the network in their 70 and 130 kVmeshed sub transmission network. To invest and rebuild in a network is very expensive. The gridowners want a reliable system that has a high reliability at a low cost.The main focus in this thesis is to examine different substation layouts. Calculating the failureintensities and unavailability for the different substation layouts gives the opportunity to do a life cyclecosts (LCC) on the different substations. With help of LCC calculations it is possible to find thesubstation that gives the lowest cost during a life time. Choosing right equipment in the grid will helpthe Vattenfall network company lower their equipment costs.The thesis work consists of mainly three parts as follows. Network modeling in PSS/EA subset of the existing sub transmission network was used in the project. This subset was taken outfrom the complete network model and modeled in PSS/E. Validation of PSS/E reliability modulesPSS/E reliability modules were new and have not been used earlier by the Vattenfall networkcompany. To be sure that the program calculates correctly a validation was performed. The main focusof the validation has been in looking if the program calculates the interrupted power correctly. Reliability analysis of different substation layoutsFor each of the substation layout the reliability was calculated. On component level (e.g. breaker,disconnector) different types of configuration were studied. To find out the best layout from aneconomical point of view a LCC calculation was also performed.The LCC calculation on the different substation layouts showed that the investment costs affect theresult very much. When the active power through the substation is low it is preferred to use asubstation that has low investment costs. At active power that is 30 MW or higher it is preferred to usethe substation with higher reliability (having higher investment cost). The result shows that using acombined breaker and disconnector instead of circuit breaker could lower the failure intensity andunavailability of substations.

The transportation infrastructure systems in the United States were built between the 50's and 80's, with 20 years design life. As most of them already exceeded their original life expectancy, state transportation agencies (STAs) are now under increased needs to rebuild deteriorated transportation networks. For major highway maintenance projects, a federal rule enforces to perform a life-cycle cost analysis (LCCA). The lack of analytical methods for LCCA creates many challenges of STAs to comply with the rule. To address these critical issues, this study aims at developing a new methodology for quantifying the future maintenance cost to assist STAs in performing a LCCA. The major objectives of this research are twofold: 1) identify the critical factors that affect pavement performances; 2) develop a stochastic model that predicts future maintenance costs of flexible-type pavement in Texas. The study data were gathered through the Pavement Management Information System (PMIS) containing more than 190,000 highway sections in Texas. These data were then grouped by critical performance-driven factor which was identified by K-means cluster analysis. Many factors were evaluated to identify the most critical factors that affect pavement maintenance need. With these data, a series of regression analyses were carried out to develop predictive models. Lastly, a validation study with PRESS statistics was conducted to evaluate reliability of the model. The research results reveal that three factors, annual average temperature, annual precipitation, and pavement age, were the most critical factors under very low traffic volume conditions. This research effort was the first of its kind undertaken in this subject. The maintenance cost lookup tables and stochastic model will assist STAs in carrying out a LCCA, with the reliable estimation of maintenance costs. This research also provides the research community with the first view and systematic estimation method that STAs can use to determine long-term maintenance costs in estimating life-cycle costs. It will reduce the agency's expenses in the time and effort required for conducting a LCCA. Estimating long-term maintenance cost is a core component of the LCCA. Therefore, methods developed from this project have the great potential to improve the accuracy of LCCA.

Overheight vehicle impact to bridge decks is a major problem in the transportation networks in the United States. An important factor that causes this problem is inadequate vertical clearance of bridges. Using steel pedestals to elevate bridge decks is an efficient and cost-effective solution for this problem. So far, steel pedestals have been used in the low seismic regions of the United States and therefore, their design has been based on providing enough strength to carry vertical loads and the lateral behavior of bridges elevated with pedestals have not been a major concern. But even in low seismic zones the seismic hazard should not be completely ignored. Also there might be some bridges in medium or high seismic regions that need to be elevated because of the lack of enough vertical clearance and using steel pedestals can be considered as an option for elevating those bridges. To address the mentioned needs, this dissertation proposes a framework to determine the structural reliability of bridges elevated with steel pedestals by developing probabilistic capacity and demand models for the slab-on-girder bridges subjected to lateral loads. This study first compares the behavior of previously tested pedestals with the behavior of elastomeric bearings in low seismic regions using statistical tests. Then, to provide a general framework, which can be applied to all bridges that are elevated with steel pedestals, this dissertation develops probabilistic capacity and demand models for steel pedestals considering all the aleatory and epistemic uncertainties of the problem. Using the developed probabilistic models along with the available models for other components of bridges, seismic fragility curves for elevated bridges are obtained and used to determine the structural reliability. Finally, this study uses the developed framework in a decision analysis that helps the engineering community and decision makers to check if the installation of steel pedestals on a specific bridge has financial justification or not. Results show that for a typical two-span slab-on-girder bridge, the use of steel pedestals has financial justification only in low seismic regions and if the societal benefits of elevating the bridge can at least cover the installation cost of pedestals.

Conventional water treatment facilities are the norm for producing potable water for U.S. metropolitan areas. Rapidly-growing urban populations, competing demands for water, imperfect water markets, and uncertainty of future water supplies contribute to high interests in alternative sources of potable water for many U.S. municipalities. In situations where multiple supply alternatives exist, properly analyzing which alternative is the most-economically efficient over the course of its useful life requires a sound economic and financial analysis of each alternative using consistent methodology. This thesis discusses such methodology and provides an assessment of the life-cycle costs of conventional water treatment using actual data from an operating surface-water treatment facility located in McAllen, Texas: the McAllen Northwest facility. This facility has a maximum-designed operating capacity of 8.25 million gallons per day (mgd), but due to required shutdown time and other limitations, it is currently operating at 78% of the designed capacity (6.44 mgd). The economic and financial life-cycle costs associated with constructing and operating the McAllen Northwest facility are analyzed using a newly-developed Excel 2 spreadsheet model, CITY H O ECONOMICS . Although specific results are applicable only to the McAllen Northwest facility, the baseline results of $771.67/acre-foot (acft)/ yr {$2.37/1,000 gallons/yr} for this analysis provide insight regarding the life-cycle costs for conventional surface-water treatment. The baseline results are deterministic (i.e., noninclusive of risk/uncertainty about datainput values), but are expanded to include sensitivity analyses with respect to several critical factors including the facility’s useful life, water rights costs, initial construction costs, and annual operations and maintenance, chemical, and energy costs. For example, alternative costs for water rights associated with sourcing water for conventional treatment facilities are considered relative to the assumed baseline cost of $2,300/ac-ft, with results ranging from a low of $653.34/ac-ft/yr (when water rights are $2,000/ac-ft) to a high of $1,061.83/ac-ft/yr (when water rights are $2,600/ac-ft). Furthermore, modifications to key data-input parameters and results are included for a more consistent basis of comparison to enable comparisons across facilities and/or technologies. The modified results, which are considered appropriate to compare to other similarly calculated values, are $667.74/ac-ft/yr {2.05/1,000 gallons/yr}.

Over the past few years, the Swedish Armed Forces (SAF) in similarity with forces inmany other countries has been undergoing a major process of change. One of the majorreforms is the government‘s decision to replace the compulsory military service with aprofessional army. In order to manage this, SAF requires tools to evaluate the long-termconsequences of different decisions regarding its manpower, such as different recruitment,training and educations policies, mission rehearsal, mission planning, and etc.These tools should, for instance, include information about different type of resourcessuch as weapon systems and materials required for conducting training and missions, asthey directly affect planning of courses, training sessions, etc. These resources have a totallife cycle cost that besides the acquisition cost includes maintenance costs, cost forspare parts and cost of human resources which are required for training and deploymentof the resource.This thesis has been performed in collaboration with FOI (Swedish Defence ResearchAgency) in order to support development of a decision support simulation tool for assistingin the personnel planning process of the SAF. The main objective is to determinethe connection between LCC (Life cycle cost) of personnel and LCC of system Hence,the study facilitates flow of information between the Human Resource Department atSAF and the Defence Material Administration (FMV) in order to base their decisionmaking process on more accurate and complete information about resource costs relatedto different activities that are important to both organizations.In this paper, the inductive approach is the chosen approach as appropriate theories arestudied and used for making hypothesis in order to create a new model. Consequentlythe interpretive approach is deployed as it is associated with this reasoning style. Furthermore,the research purpose is exploratory as it is essential to identify the resourcescost factors and the relations between them.The research strategy is case study and the utilized technique for collecting primary datais interview. The secondary data is gathered by studying hard or digital copy of books,articles, journals, handbooks and dictionaries.Hence, through a set of interviews, information about different activities regarding theeducation and operation phases of the fighter pilots at the Swedish Air Force has beencollected. As a result a corresponding model consisting of resources employed in thoseiiactivities and their relation has been developed. The model is based on the Unified EnterpriseCompetence Modelling Language (UECML).The contributions of this thesis are (1) Identification of the cost factors of personnelrelatedactivities including courses, training sessions and missions, 2) Classification ofcost factor elements in a number of classes, and 3) Illustrating the connections betweenthe classes using UECML.

Advances in materials technology, information and management systems have led to improvements in the engineering design, procurement, construction, installation and commissioning of process columns. The development of the front-end engineering design (FEED) process has led to the incorporation of best practices in the specification of equipment on projects during the design phase. The aim of the research is to investigate whether technical specifications have an impact on the life cycle costs of process columns. Adding to the initial capital cost of equipment, in the form of technical specification requirements, in an attempt to reduce life cycle costs, is always challenged during the project phase of a product life cycle. The principle of designing for the full product life cycle of process columns requires that consideration for both the project and operating life cycle be made at the stage of basic engineering. What is important to note is that the potential for life cycle cost savings at the beginning of a product life cycle is higher than during the operating life cycle. Figure S.1 illustrates this concept, and what is observed is that the potential for life cycle cost savings diminishes as the product life progresses over time. Process columns were chosen as the type of equipment to be investigated based on the nature, size and complexity of the equipment when compared to other equipment on a processing unit. Process columns are amongst the highest capital cost pieces of equipment in petrochemical units and usually have many auxiliary pieces of equipment associated with it in a system i.e. reboilers, condensers, pumps etc. / Dissertation (MEng)--University of Pretoria, 2009. / Graduate School of Technology Management (GSTM) / unrestricted