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Growing needs for maintenance, repair, and replacement (MRR) of existing transportation infrastructure signifies the importance of new and innovative contracting strategies. Among the emerging contracting methods in the area of transportation infrastructure management is long-term performance-based maintenance contracts, also known as performance-based contracting (PBC). To date, PBC has not been implemented in the area of bridge infrastructure maintenance management due to uncertainties in the bridge deterioration process and challenges in modeling performance. The main objective of this research is to develop short- and long-term optimal MRR plans for bridge decks under PBC settings. This objective necessitates the development of a performance model to define the current condition of bridges and predict their future deterioration rates. The performance model is essential to select appropriate MRR actions that enable planning these actions and estimating the needed budget. The research introduces an integrated condition as a key performance indicator of the bridge component (i.e., bridge deck). Further, an associated level of service (LOS) threshold is defined. The output of this research is a decision support model for selecting optimal rehabilitation strategies while maintaining a defined performance LOS and budget constraints. A modified genetic algorithm (GA) is developed to perform the optimization of resources under the defined LOS and is coded in MATLAB version R2014a software to perform the needed analysis. The decision support model is evaluated with a real case study for a bridge located in Quebec, Canada. Sensitivity analysis is performed to evaluate the impacts of the decision variables against the cost. For instance, the analysis proved that improving the LOS by 18% requires an increase of an MRR budget by about 51%. Research findings concluded that integrating the PBC approach into the decision-making process offers better results in long-term plans. The focus of this study has mainly been on bridge decks. Future work may target expanding to the other bridge components and additional related assets. [ABSTRACT FROM AUTHOR]

Purpose: Although ground penetrating radar (GPR) technology is commonly used to assess the condition of reinforced-concrete (RC) bridge decks, the GPR data interpretation is not straightforward. Further, the thresholds that define the severity of deterioration are selected arbitrarily. This paper aims to solve a problem associated with GPR results generated by using a numerical amplitude method to assess corrosiveness of bridge decks. Design/methodology/approach: Data, for more than 50 different bridge decks, were collected using a ground-coupled antenna. Depth-correction was performed for the collected data to normalize the reflected amplitude. Using k-means clustering technique, the amplitude values of each bridge deck were classified into four categories. Later, statistical analysis was performed where the threshold values of different categories of corrosion and deterioration are chosen. Monte-Carlo simulation technique was used to validate the value of these thresholds. Moreover, a sensitivity analysis was performed to realize the effect of changing the thresholds in the areas of corrosion. Findings: The final result of this research is a four-category (good, fair, poor and critical) GPR scale with three fixed numerical thresholds (−7.71 dB, −10.04 dB and −14.63 dB) that define these categories. Besides, deterioration curves have been modeled using Weibull function and based on GPR outputs and corrosion areas. Originality/value: The developed numerical GPR-based scale and deterioration models are expected to help the decision-makers in assessing the corrosiveness of bridge decks accurately and objectively. Hence, they will be able to take the right intervention decision for managing these decks. [ABSTRACT FROM AUTHOR]

The manuscripts involve the performance of GPR in defect detection, novel data processing and interpretation techniques, deterioration and rehabilitation models, and GPR applications in the inspection, corrosion mapping, condition assessment, and asset management of concrete structures. This Special Issue includes a collection of papers that address the practical applications of GPR to various civil infrastructure systems. [Extracted from the article]

In this study, the applications and the limitations of the Ground-penetrating radar (GPR) investigation have been addressed with the main objective of improving the efficient GPR application of subsurface surveys on Korean expressways. The depth of investigation and detection performance of anomalous objects have been studied using two different types of multichannel GPR on the Korean Expressway Corporation's nondestructive testing testbed for subsurface detection. Based on the field survey, it was found that utilizing the plane view by depth, cross-sectional and longitudinal profile data of the multichannel GPR simultaneously, analysis and evaluation of the GPR signals are more efficient and practical. Although there was a difference in the frequency of use, the precision difference between two GPR is almost similar in the investigation depth and detection performance of the pavement subsurface anomaly. Under an asphalt concrete standard pavement section, the effective depth of cavity detection is 1–1.5 m, while detection under concrete pavement is less than 1.0 m. In addition, there is still a need to calibrate depths using field cores when constructing a 3D underground facility map. [ABSTRACT FROM AUTHOR]