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Currently, in North America, a large percentage of infrastructure assets, including education and healthcare buildings, are deteriorating rapidly due to age and over capacity. The budget constraints under which municipalities and public agencies operate also make the sustainability of these buildings a serious challenge. This is particularly so when capital renewal programs are downsized to save money, thus hindering the proper inspection of buildings and the allocation of renewal funds. In addition, building inspections and condition assessments are generally resource intensive, subjective, time-consuming, and costly. To support capital renewal decisions that pertain to buildings, this research introduces a comprehensive condition assessment framework that overcomes the drawbacks of the existing processes. A prototype of the framework utilizing hand-held devices has been developed and tested on the capital renewal program of the Toronto District School Board (TDSB). The framework is innovative on three main fronts: (1) it utilizes available reactive-maintenance records to predict the condition of components and to prioritize inspection tasks among limited available resources; (2) it employs a unique visual guidance system that is based on extensive surveys and field data collection to support uniform condition assessment of building components; and (3) it introduces a location-based inspection process with a standardized building hierarchy. The research contributes to restructuring the inspection and condition assessment processes, providing a better understanding of the interactions among building components, integrating capital renewal and maintenance data, and developing a practical condition assessment framework that is economical, less-subjective, and suitable for use by individuals with less experience. The framework also incorporates permanent documentation of the condition of the asset along its life cycle, and aids in scheduling inspections so as to maintain low-cost condition tracking. Ultimately, the proposed system will provide timely and sufficient information to facilitate accurate repair decisions for maintaining the building infrastructure. The framework is of benefit to both researchers and practitioners. Its formulation is innovative and helps building owners automate most inspection tasks, quantify the impact of alternative funding scenarios, and reduce the cost of asset management. In addition, because asset management is a less-developed multi-billion dollar business, the research is expected to establish leading technology and know-how that will help Canadian companies gain a competitive global advantage. At the municipality level, the proposed prototype is expected to assist managers in arriving at decisions that will ensure the cost-effective operation of buildings and uninterrupted service to the public.

Currently, in North America, a large percentage of infrastructure assets, including education and healthcare buildings, are deteriorating rapidly due to age and over capacity. The budget constraints under which municipalities and public agencies operate also make the sustainability of these buildings a serious challenge. This is particularly so when capital renewal programs are downsized to save money, thus hindering the proper inspection of buildings and the allocation of renewal funds. In addition, building inspections and condition assessments are generally resource intensive, subjective, time-consuming, and costly. To support capital renewal decisions that pertain to buildings, this research introduces a comprehensive condition assessment framework that overcomes the drawbacks of the existing processes. A prototype of the framework utilizing hand-held devices has been developed and tested on the capital renewal program of the Toronto District School Board (TDSB). The framework is innovative on three main fronts: (1) it utilizes available reactive-maintenance records to predict the condition of components and to prioritize inspection tasks among limited available resources; (2) it employs a unique visual guidance system that is based on extensive surveys and field data collection to support uniform condition assessment of building components; and (3) it introduces a location-based inspection process with a standardized building hierarchy. The research contributes to restructuring the inspection and condition assessment processes, providing a better understanding of the interactions among building components, integrating capital renewal and maintenance data, and developing a practical condition assessment framework that is economical, less-subjective, and suitable for use by individuals with less experience. The framework also incorporates permanent documentation of the condition of the asset along its life cycle, and aids in scheduling inspections so as to maintain low-cost condition tracking. Ultimately, the proposed system will provide timely and sufficient information to facilitate accurate repair decisions for maintaining the building infrastructure. The framework is of benefit to both researchers and practitioners. Its formulation is innovative and helps building owners automate most inspection tasks, quantify the impact of alternative funding scenarios, and reduce the cost of asset management. In addition, because asset management is a less-developed multi-billion dollar business, the research is expected to establish leading technology and know-how that will help Canadian companies gain a competitive global advantage. At the municipality level, the proposed prototype is expected to assist managers in arriving at decisions that will ensure the cost-effective operation of buildings and uninterrupted service to the public.

This thesis explores the Bohmann Park neighborhood of Washington County as a case study of contemporary style in Oregon. As both individual and the largest grouping of homes by Robert Rummer, Bohmann Park informs treatment of Rummer homes and contemporary resources. Nationally, contemporary homes by architects and builders have been recognized for their architectural and historic value through the historiography, National Register listing, and local protections. Modern architecture in Oregon has yet to be equally rigorously explored. Rummer’s prolific work is an ideal point of exploration. Within the context of architectural history and preservation practice, two condition assessments of individual residences in the neighborhood analyze the varied care and common threats faced by these resources. The adverse effects faced by Bohmann Park from the City of Portland’s Fanno Creek Pump Station and its mitigation efforts explore challenges faced by the subdivision as a potential historic district.

The condition of water and wastewater pipelines has been deteriorating with time and since this infrastructure is out-of-sight, the assessment has been neglected over the years. The advancement of technology in various fields has provided pathway for development of several technologies for assessment of the condition of pipeline systems. However, there is no standard guidance or tool for the utilities to use these technologies appropriately. The utilities are unaware of the present state-of- the- art technologies. The predictability and condition assessability indices will help utilities predict a probable failure and take steps to prevent it. The predictability index will indicate the inherent, theoretical predictability of key types of pipe failures. The pipe failure predictability index would be a score calculated by identifying high priority pipe types, characterizing their failure modes, mechanism, conditions, and indicators, reliability of indicators, lead-time of the indicators, and other factors. The condition assessability index will indicate the technical and economical methods of preventing key types of pipe failures. The pipe failure condition assessability index is similar to the predictability index, but it takes into account the capability of existing inspection technologies for measuring the required failure indicator parameters. Prestressed Concrete Cylinder Pipes are used in large diameter water pipelines throughout the United States to convey large volumes of water. Prestressed Concrete Cylinder Pipes are complex composite pipes. Therefore, prediction and prevention of failure of these pipelines is complex and requires a better understanding of the system. This research concentrates around development of Predictability and Condition Assessability Indices for PCCP pipelines. / Master of Science

There is an unprecedented need to manage our deteriorating water infrastructure systems effectively to mitigate the enormous consequences of their premature failure such as loss of service, money, time, damage to other infrastructure, and damage to property. Most of the water utilities understand this need and are implementing asset management approaches and technologies to increase the overall service life of their assets. However, to indeed achieve sustainable water infrastructure systems, there is a requirement to implement a risk-based asset management program which provides a more comprehensive approach to manage these aging assets. A risk-based asset management program assesses and manages the risk of failure associated with the water infrastructure assets and helps water utilities in prioritizing their assets for renewal. This program identifies the critical assets for renewal and saves the money and time invested in the renewal of 'not so critical' assets. This research incorporates an extensive literature and practice review on risk-based asset management of pipes, valves, and hydrants. The risk-based asset management consist of the following four major components: (1) understanding the deterioration modes and mechanisms, (2) implementing risk assessment and management approaches, (3) implementing condition assessment approaches and technologies, and (4) implementing asset renewal approaches and technologies. This research aims to provide enhanced guidelines based on the EPA 10 step asset management program which will help water utilities in developing a risk-based asset management program as well as in improving their existing asset management program. This research combines the in-depth knowledge gained through a state-of-the-art literature review and practice review. The practice review is conducted to capture the real world application of the risk-based asset management through interviews with the water utilities across the united states. This research has also compiled the knowledge gained by already published case studies to provide a more comprehensive overview of the current practices and trend in the risk-based asset management of drinking water pipelines, valves, and hydrants. / Master of Science

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No description available.

Mechanical waves provide information about the stiffness and the condition of a medium; thus, changes in medium conditions can be inferred from changes in wave velocity and attenuation. Non-destructive testing (NDT) methods based on ultrasonic waves are often more economical, practical and faster than destructive testing. Multichannel analysis of surface waves (MASW) is a well-established surface wave method used for determination of the shear-wave profile of layered medium. The MASW test configuration is also applicable to assess the condition of concrete elements using appropriate frequency range. Both attenuation and dispersion of ultrasonic waves can be evaluated by this technique. In ultrasonic testing, the characterization of a medium requires the precise measurement of its response to ultrasonic pulses to infer the presence of defects and boundary conditions. However, any ultrasonic transducer attached to a surface affects the measured response; especially at high frequencies. On the other hand, ultrasonic transducers available for engineering application are mostly used to measure wave velocities (travel time method). Therefore, these transducers do not have a flat response in the required frequency range. Moreover, in the case of full-waveform methods, the recorded signals should be normalized with respect to the transfer functions of the transducers to obtain the real response of the tested specimen. The main objective of this research is to establish a comprehensive methodology based on surface wave characteristics (velocity, attenuation and dispersion) for condition assessment of cemented materials with irregular defects. To achieve the major objective, the MASW test configuration is implemented in the ultrasonic frequency range. The measured signals are subjected to various signal processing techniques to extract accurate information. In addition, a calibration procedure is conducted to determine the frequency response functions (FRF) of the piezoelectric accelerometers outside their nominal frequency range. This calibration is performed using a high-frequency laser vibrometer. This research includes three main studies. The first study introduces the calibration approach to measure the FRFs of the accelerometers outside of their flat frequency range. The calibrated accelerometers are then used to perform MASW tests on a cemented-sand medium. The original signals and the corrected ones by eliminating the effect of the FRFs are used to determine material damping of the medium. Although, the damping ratios obtained from different accelerometers are not same, the values from the corrected signals are found closer to the characteristic damping value compared to those from the uncorrected signals. The second study investigates the sensitivity of Rayleigh wave velocity, attenuation coefficient, material damping and dispersion in phase velocity to evaluate the sensitivity of these characteristics to the damage quantity in a medium. The soft cemented-sand medium is preferred as the test specimen so that well-defined shaped defects could be created in the medium. MASW test configuration is implemented on the medium for different cases of defect depth. The recorded signals are processed using different signal processing techniques including Fourier and wavelet transforms and empirical mode decomposition to determine the surface wave characteristics accurately. A new index, ‘dispersion index’, is introduced which quantifies the defect based on the dispersive behaviour. All surface wave characteristics are found capable of reflecting the damage quantity of the test medium at different sensitivity levels. In the final study, the condition assessment of six lab-scale concrete beams with different void percent is performed. The beam specimens involving Styrofoam pellets with different ratios are tested under ultrasonic and mechanical equipment. The assessment produce established in the second study with well-defined defects is pursed for the beams with irregular defects. Among the characteristics, attenuation, P and R-wave velocities and dispersion index are found as the promising characteristics for quantifying the defect volume.

Performance-based Maintenance Contracts (PBMCs) are increasingly being used for roadway maintenance as an alternative to method-based specifications. However, this technique is still relatively new and several issues have not been adequately addressed in the literature. The paper provides a systematic process for developing quality assurance measures to be used within these contracts. The process addresses key issues, including the development of performance standards and targets, a method for monitoring the roadside performance, and a methodology for developing pay adjustment factors. The developed performance standards presented in the paper are easily measured and assigned grades of pass, fail, or not applicable. The required sample size is a function of the project characteristics, including performance variability along the project, required confidence level, and allowable tolerance. Finally, the pay adjustment curves are a function of the initial project LOS, the target LOS, and the maintenance cost to achieve the target LOS.