This dissertation focused on the new performance-based teacher evaluation system implemented in the Commonwealth of Virginia. Eight school districts were granted an implementation waiver for one year making the 2013-2014 school year the implementation year for those school districts. A mixed methodology study was designed to understand teacher perceptions in one waiver school district in the Commonwealth of Virginia. The purposes of this study were to collect empirical evidence on the implementation of the new performance-based teacher evaluation system by comparing teachers' and principals' perceptions at three elementary schools to teachers' perceptions in the school district, identified as District Z and were to add to the research base on policy implementation theories and teacher evaluation. Findings and analysis of research questions were based on the responses of 357 teacher participants, two district directors, and three principals. Policy implementation research suggested access to resources and support along with an alignment of beliefs and values resulted in more effective implementation practices. Conclusions of this study, while limited to the district studied, suggested professional development on the new performance-based teacher evaluation system, including the Uniform Performance Standards and SMART goals, would provide teachers and principals with the increased knowledge to use as a resource during new implementation phases. Additionally, involvement in the design and modification of the teacher evaluation system would encourage participation and provide opportunities for teachers and principals to develop shared values regarding aspects of the evaluation system. / Ed. D.

Performance based contracting in the transportation arena is a rather recently implemented concept which has a few number of applications in the United States up to date. Nonetheless, the US Department of Transportation has vigorously promoted (by issuing memorandums to be distributed to the Highway Agencies and State Departments of Transportation) the conversion of traditional contracts to performance based contracts to reach a goal of 80% of the service contracts and actions being performance based by the end of fiscal year 2004 (Tomanelli 2003.) Virginia Department of Transportation (VDOT) has been one of the first state agencies that took the initiative of using a performance based contract for the maintenance of a portion of its interstate highway system. This initiative resulted in the establishment of the 'Comprehensive Agreement for Interstate Highway Asset Management Services' between VDOT and a private contractor in 1996 which resulted in the privatization of highway maintenance services. One of the important aspects of this contract related to this research is that it does not encompass any warranty clauses. In other words, the contractor does not provide any warranty to the VDOT for the services it is obligated to undertake. The contract is mute in this subject, making the contractor incur no liability for the underperformance of the maintenance activities. According to this research, this might lead to some cases which VDOT would not be willing to encounter. Just like performance based contracting, the use of warranties in highway contracts in the United States is a quite new concept which mainly dates back to 1995. There are different views possessed by different parties about the possible outcomes of implementing warranties in highway contracts. Nonetheless, this research proposes that the incorporation of warranty clauses into the VDOT issued performance based road maintenance contracts is vital to ensure the quality and durability of the work after the project completion. According to this research, warranty clauses, if developed carefully, give the contractor the motivation to implement superior maintenance practices to improve the overall conditions of the assets during the contract period. This is done in order to lengthen the life of each asset item and achieve the long term performance. Ultimately, the incorporation of warranty clauses is believed to reduce the risk imposed upon VDOT. Within the context of the discussion presented above, this research first illustrates that the complete satisfaction of one of the parties (VDOT) may be in question due to the absence of the warranty clauses within the contract, then lists and explores the benefits that would/may be gained by the incorporation of warranty clauses into the contract, and finally develops a warranty clause template and proposes it to be used in the future performance based road maintenance contracts issued by VDOT. At the bottom line, this study aspires to help the party in question (VDOT) to reduce the risk imposed upon it and to improve the future performance based road maintenance contracts it will issue. This research uses the VDOT contract as a baseline to define the problem and to propose a solution (i.e. the developed warranty clause template) for that. Nonetheless, some of the principles and approaches used during the development of the warranty clause template can also be referred to for the development of warranty clauses for the performance based road maintenance contracts issued by the other state DOTs. / Master of Science

The United States (U.S.) faces significant housing challenges, including a shortage of affordable housing and high rates of homelessness. This, combined with the pursuit of sustainable and resilient communities, has positioned Cross-Laminated Timber (CLT) modular structures as a promising alternative due to their environmental, mechanical, and prefabrication advantages. However, a comprehensive study of their seismic performance and risk across the U.S. is needed to establish CLT modular construction as a resilient housing option. Therefore, this thesis assesses the seismic risk and performance of five modular CLT houses, studying (i) the variability of their collapse fragility curves across the U.S., (ii) the conditional probability of collapse under Maximum Considered Earthquake (MCE) intensities, and (iii) the unconditional probabilities of experiencing non-structural damage and collapse within 50 years for ten representative locations. The houses use the latest platform-constructed CLT shear wall lateral-force resisting system included in ASCE 7-22 (2022) and were designed using prescriptive code-based methods to represent a feasible construction alternative. The analyses were conducted under the performance-based earthquake engineering framework. Ground motion data sets were established for three seismic regions: (1) Western U.S. with forward-directivity pulses, (2) Western U.S. without forward-directivity pulses, and (3) Central and Eastern U.S. Numerical models for each house were developed and calibrated using OpenSees to perform nonlinear static and time history analyses. The Multiple Stripe Analysis procedure was used to derive the conditional probability of collapse fragility curves and interstory drift distributions, which, along with generic damage fragilities and seismic hazard curves, estimated the probabilities of non-structural damage and collapse within 50 years at representative locations. The results indicate that differences in ground motion characteristics, including pulse-like motions, do not significantly impact the collapse fragility curves. All houses satisfy the ASCE 7-22 (2022) target of a 10% conditional probability of collapse at MCE intensity. Expected non-structural damage is within acceptable limits compared to common performance objectives. Increasing house strength does not significantly enhance performance in non-structural damage states, as performance is primarily influenced by the hazard curve of the location. The unconditional probability of collapse within 50 years remains conservatively low, satisfying the ASCE 7-22 (2022) performance objective of a 1% probability of collapse within 50 years. In summary, the consistent behavior, low collapse risk, acceptable non-structural damage levels, and potential improvements through performance-based design make modular CLT houses a reliable, resilient, and high-performance seismic housing alternative in the U.S. / Master of Science / The United States (U.S.) faces significant housing challenges, including a shortage of affordable housing and high rates of homelessness. These, along with the pursuit of sustainability and resilience against natural disasters in communities, positioned modular Cross-Laminated Timber (CLT) structures as a promising alternative. CLT consists of wood panels that are environmentally friendly, strong, and suitable for prefabrication. They enable prefabrication in parts (modules) of entire homes that can be easily assembled at construction sites. Understanding their behavior during seismic events is crucial to determine whether they can resist collapse and minimize damage that causes economic losses. Ground motions in the Western U.S. differ from those in the Central and Eastern U.S., affecting structures in distinct ways. To assess these effects, computer simulations are used to calculate and compare the probability of modular CLT houses collapsing in these regions. Additionally, the study estimates the probability of these houses experiencing damage and collapse in 50 years when constructed at ten different locations. The results show the houses perform satisfactorily and consistently under seismic events and can constitute a viable alternative for housing in the U.S. Differences in earthquake characteristics across the country do not significantly affect the safety of CLT modular houses. They meet and often exceed the safety standards set by building codes for collapse under seismic events. Additionally, any expected damage is also within acceptable limits. This makes them a high-quality alternative for earthquake-resistant housing.

This research adds to the literature and provides insight to practice via three essays that increase understanding about the applications and consequences of the two new approaches to the after-sales service governance: warranty contract and performance-based contracts. First, we attempted to enhance our knowledge of the modeling of the after-sales service process. In the first essay, the research papers with analytical models of after-sales services to present current trends, issues, and future research directions in the literature are classified. In the second essay, the effect of the warranty contract on the supplier's product quality improvement efforts in the context of capital goods is examined. Three sets of optimization models reveal that the existence of a warranty improves product quality. In the third essay, the performance-based contract is examined in the context of the warranty contract. The numerical experimentations conducted demonstrate that the performance-based contract is superior to the warranty contract in terms of the supplier's product quality efforts and the customer's total cost of after-sales services. The alignment of incentives based on the product performance tackles the issues presented in the traditional after-sales service contracting. Collectively, the three studies presented in this research expand our understanding of after-sales service contracts. Thus, the research presents managerial implications and adds to the existing body of knowledge in after-sales service research.

Performance-based contracting (PBC) is an outcome-based product support strategy that provides efficient performance solutions for buyers. Suppliers under performance-based contracting are rewarded after achieving desired performance objectives. While current scholarship has deepened our knowledge of the benefits of PBC, the particular factors behind effective and efficient performance-based contracts (PBCs) are still vague. Thus, this dissertation will focus on essential dimensions for the successful PBC. There remains a great deal that is not understood about the success factors for effective PBCs. When looking at the critical criteria for the selection of suppliers in the context of PBC, even less is known. This dissertation contains three essays with the purpose of: (1) investigating the effect of supply chain collaboration and upfront investments on the benefits of the PBC; (2) exploring supplier selection criteria for successful PBC; and (3) examining the effect of contract length and fleet size on upfront investments for effective and efficient PBC. These three essays offer a solid foundation for theoretical and practitioner understanding for effective PBCs.

A Engenharia de Ventos Baseada em Desempenho (Performance-based Wind Engineering - PBWE) é uma filosofia de projeto que preconiza identificar e quantificar as incertezas envolvidas no projeto estrutural a fim de assegurar níveis previsíveis de desempenho às edificações, não mais gerenciando o risco através da clássica abordagem determinística. Contudo, devido à recente proposição da metodologia, ainda há poucos estudos relacionados à PBWE, cada qual apresentando diferentes limitações. Assim, o presente trabalho propõe uma adaptação da metodologia da Engenharia de Ventos Baseada em Desempenho à análise probabilística do comportamento de torres metálicas, avaliando diferentes modelos de cálculo para estimativa das forças do vento neste tipo de estrutura. Para tanto, investigou-se as incertezas envolvidas na caracterização do campo de ventos e da resistência estrutural e foram analisados quatro métodos distintos para a estimativa das forças de vento em torres metálicas: dois procedimentos de cálculo correspondentes à norma brasileira de ventos ABNT NBR 6123:1988 (ABNT, 1988), a metodologia de Davenport (1993) e a de Holmes (1994). Um estudo de caso envolvendo a estimativa da confiabilidade de uma torre de telecomunicação também foi conduzido. Constatou-se que ambos os procedimentos de cálculo admitidos conduzem a níveis de segurança de mesma ordem de grandeza e que a elaboração de projetos de torres considerando a direção de incidência do vento como sendo a mais desfavorável à estrutura é demasiadamente conservadora. Como contribuição, verifica-se que o projeto ótimo de torres pode ser alcançado com base no nível de segurança desejado para diferentes velocidades máxima de vento associadas a intervalos de recorrência específicos. / Performance-based Wind Engineering (PBWE) is a design philosophy that aims to identify and quantify the uncertainties involved in the structural design in order to ensure predictable performance levels to buildings, no longer managing risk through the classical deterministic approach. However, due to the recent proposal of the methodology, there are few studies related to PBWE, each presenting different limitations. Thus, this paper proposes an adaptation of the Performance-based Wind Engineering methodology to the probabilistic analysis of the behavior of steel towers, evaluating different calculation models for estimating wind forces on this type of structure. To this end, uncertainties involved in the characterization of the wind field and structural strength were investigated and four different methods for the estimation of wind forces on steel towers were analyzed: two procedures relative to the Brazilian winds standard ABNT NBR 6123:1988 (ABNT, 1988), and the methodologies of Davenport (1993) and Holmes (1994). A case study concerning the reliability estimation of a telecommunication tower was also conducted. It was found that both assumed calculation procedures lead to security levels of the same order of magnitude and that the design of towers considering that the wind always blows from the worst direction is too conservative. As a contribution, it is found that the optimum design of towers can be achieved based on the desired security level for different maximum wind speeds associated to specific recurrence intervals.

A Engenharia de Ventos Baseada em Desempenho (Performance-based Wind Engineering - PBWE) é uma filosofia de projeto que preconiza identificar e quantificar as incertezas envolvidas no projeto estrutural a fim de assegurar níveis previsíveis de desempenho às edificações, não mais gerenciando o risco através da clássica abordagem determinística. Contudo, devido à recente proposição da metodologia, ainda há poucos estudos relacionados à PBWE, cada qual apresentando diferentes limitações. Assim, o presente trabalho propõe uma adaptação da metodologia da Engenharia de Ventos Baseada em Desempenho à análise probabilística do comportamento de torres metálicas, avaliando diferentes modelos de cálculo para estimativa das forças do vento neste tipo de estrutura. Para tanto, investigou-se as incertezas envolvidas na caracterização do campo de ventos e da resistência estrutural e foram analisados quatro métodos distintos para a estimativa das forças de vento em torres metálicas: dois procedimentos de cálculo correspondentes à norma brasileira de ventos ABNT NBR 6123:1988 (ABNT, 1988), a metodologia de Davenport (1993) e a de Holmes (1994). Um estudo de caso envolvendo a estimativa da confiabilidade de uma torre de telecomunicação também foi conduzido. Constatou-se que ambos os procedimentos de cálculo admitidos conduzem a níveis de segurança de mesma ordem de grandeza e que a elaboração de projetos de torres considerando a direção de incidência do vento como sendo a mais desfavorável à estrutura é demasiadamente conservadora. Como contribuição, verifica-se que o projeto ótimo de torres pode ser alcançado com base no nível de segurança desejado para diferentes velocidades máxima de vento associadas a intervalos de recorrência específicos. / Performance-based Wind Engineering (PBWE) is a design philosophy that aims to identify and quantify the uncertainties involved in the structural design in order to ensure predictable performance levels to buildings, no longer managing risk through the classical deterministic approach. However, due to the recent proposal of the methodology, there are few studies related to PBWE, each presenting different limitations. Thus, this paper proposes an adaptation of the Performance-based Wind Engineering methodology to the probabilistic analysis of the behavior of steel towers, evaluating different calculation models for estimating wind forces on this type of structure. To this end, uncertainties involved in the characterization of the wind field and structural strength were investigated and four different methods for the estimation of wind forces on steel towers were analyzed: two procedures relative to the Brazilian winds standard ABNT NBR 6123:1988 (ABNT, 1988), and the methodologies of Davenport (1993) and Holmes (1994). A case study concerning the reliability estimation of a telecommunication tower was also conducted. It was found that both assumed calculation procedures lead to security levels of the same order of magnitude and that the design of towers considering that the wind always blows from the worst direction is too conservative. As a contribution, it is found that the optimum design of towers can be achieved based on the desired security level for different maximum wind speeds associated to specific recurrence intervals.

Performance-based contracting (PBC) redefines the relationships between suppliers and buyers and differs from traditional contracting approaches with its reward/payment scheme, emphasis on the performance outcomes, increased supplier autonomy, and transfer of risk and responsibilities to suppliers. Given the 70% of life cycle costs of products/systems reside in sustainment, PBC has led to substantial improvements in availability, maintainability, reliability, and thus total cost of ownership of systems/products. Though PBC has changed the way of doing business and its presence has increased across multiple industry, private and public sectors, for profit and not-for-profit, its implications on various aspects of logistics and supply chain management have been understudied. It is important to explore and establish evidence regarding these implications through academic rigor. Therefore, this three-essay dissertation aims to give some insight regarding structural and behavioral implications of PBC using a multi-method approach. Specifically, it (1) explores the relationship between PBC and supply chain resilience (SCRES), (2) examines the supplier goal commitment (i.e., motivation) in PBC, (3) proposes a mathematical model to find optimal contract length, periodic contract price and investment that concurrently maximizing supplier profit and satisfying buyer requirements. This dissertation offers theoretical and managerial contributions as well.

Master of Science / Department of Architectural Engineering and Construction Science / Kimberly W. Kramer / The basic tenets of performance based seismic design (PBSD) are introduced. This includes a description of the underlying philosophy of PBSD, the concept of performance objectives, and a description of hazard levels and performance indicators. After establishing the basis of PBSD, analysis procedures that fit well within the PBSD framework are introduced. These procedures are divided into four basic categories: linear static, linear dynamic, nonlinear static, and nonlinear static. Baseline FEMA requirements are introduced for each category. Each analysis category is then expanded to include a detailed description of and variations on the basic procedure. Finally, optimization procedures that mesh well with a PBSD framework are introduced and described. The optimization discussion focuses first on the solution tools needed to effectively execute a PBSD multi-objective optimization procedure, namely genetic and evolutionary strategies algorithms. Next, multiple options for defining objective functions and constraints are presented to illustrate the versatility of structural optimization. Taken together, this report illustrates the unique aspects of PBSD. As PBSD moves to the forefront of design methodology, the subjects discussed serve to familiarize engineers with the advantages, possibilities, and finer workings of this powerful new design methodology.

Στην παρούσα εργασία παρουσιάζεται μία νέα βασισμένη στην επιτελεστικότητα μέθοδος αντισεισμικού σχεδιασμού χωρικών μεταλλικών κατασκευών, οι οποίες υπόκεινται σε σεισμικές διεγέρσεις μακρινού πεδίου. Η μέθοδος αυτή συνδυάζει τα πλεονεκτήματα της μεθόδου σχεδιασμού με βάση τις δυνάμεις και με βάση της μετατοπίσεις και γι’ αυτό ονομάζεται υβριδική δυνάμεων-μετατοπίσεων (ΥΔΜ) μέθοδος. Για τη δημιουργία της προτεινόμενης μεθόδου γίνεται παραμετρική σεισμική μελέτη κανονικών καμπτικών μεταλλικών κτιρίων με και χωρίς τυχηματικές εκκεντρότητες, καθώς και μεταλλικών κτιρίων τα οποία εμφανίζουν γεωμετρικές μη κανονικότητες λόγω ανομοιόμορφης καθ’ ύψος κατανομής μάζας και λόγω παρουσίας εσοχών. Αρχικά γίνεται μια βιβλιογραφική ανασκόπηση για τις ήδη υπάρχουσες μεθόδους, όσον αφορά στο σχεδιασμό και στην εκτίμηση της ανελαστικής σεισμικής απόκρισης επίπεδων και χωρικών κατασκευών. Στη συνέχεια περιγράφεται η επιλογή των παραμέτρων και η όλη διαδικασία που ακολουθήθηκε για τη δημιουργία μίας βάσης δεδομένων σεισμικής απόκρισης η οποία απαίτησε 43176 μη γραμμικές δυναμικές αναλύσεις. Με βάση την στατιστική επεξεργασία που έγινε προέκυψαν εμπειρικές σχέσεις αντισεισμικού σχεδιασμού, οι οποίες καθιστούν δυνατό τον έλεγχο της βλάβης κατά το σχεδιασμό νέων κατασκευών και οι οποίες λαμβάνουν υπόψη την επιρροή διαφόρων παραμέτρων, όπως ο αριθμός ανοιγμάτων, ο αριθμός ορόφων, η μορφή της κάτοψης, καθώς και η μη κανονικότητα της κατασκευής. Επιπλέον εξετάστηκε η επιρροή της φυσικής μονοαξονικής εκκεντρότητας, μεταξύ κέντρου μάζας και κέντρου δυσκαμψίας στην ανελαστική σεισμική απόκριση χωρικών κατασκευών με μεικτό σύστημα ανάληψης σεισμικών δυνάμεων. Ωστόσο, επειδή ο αριθμός των κτιρίων που χρησιμοποιήθηκαν ήταν μικρός, δεν έγινε προσπάθεια κατασκευής κάποιων εμπειρικών σχέσεων από τα αποτελέσματα που προέκυψαν για αυτήν την περίπτωση. Τα πλεονεκτήματα της νέας ΥΔΜ μεθόδου αντισεισμικού σχεδιασμού, παρουσιάζονται μέσω τριών παραδειγμάτων, όπου η προτεινόμενη μέθοδος συγκρίνεται με τη μέθοδο σχεδιασμού με βάση τις δυνάμεις στην οποία βασίζονται όλοι σχεδόν οι υπάρχοντες αντισεισμικοί κανονισμοί. Από τη σύγκριση που γίνεται προκύπτει ότι, σε αντίθεση με τη μέθοδο των δυνάμεων, η ΥΔΜ μέθοδος μπορεί να κάνει κατά το σχεδιασμό άμεσο έλεγχο της βλάβης. / This dissertation proposes a preliminary performance-based seismic design method for three-dimensional steel building frames under ordinary (i.e., without near fault effects) ground motions. This method combines the advantages of the well-known force-based and displacement-based seismic design methods in a hybrid force/displacement design scheme. The proposed method was developed based on the results of an extensive parametric study involving the inelastic seismic response of regular and irregular moment resisting frames (MRFs). The regular MRFs are structures with and without the presence of accidental eccentricities, whereas the irregular MRFs, are structures with vertical mass irregularities and structures with setbacks. In total 146 buildings have been studied. The results of 43176 nonlinear dynamic analyses were post-processed in order to create a databank with the response quantities of interest. The main parameters that affect the inelastic response of the examined structures were recognised after the statistical analysis of the created response. Based on regression analysis, a procedure in terms of simple formulae for estimating the maximum roof displacement, the maximum interstorey drift ratio and the maximum rotation ductility along the height of the frame was developed. In addition, the inelastic seismic response of 20 buildings with natural eccentricities has been studied, which combines MRFs with buckling restrained braces. However, the conclusions of this case cannot be generalized, because only few cases were investigated. Comparison of the proposed method with the procedures adopted in current seismic design codes demonstrated the efficiency of the former. The results revealed that the proposed procedure seems to be more rational and efficient than the procedures used in the current seismic design codes. Nonlinear time history analyses proved the consistency of the proposed method to accurately estimate inelastic deformation demands and the tendency of the current seismic design codes to overestimate the maximum roof displacement and underestimate the maximum interstorey drift ratio along the height of the frames.