Thomas M. Juliano

Framework for Automatic Condition Assessment of Culverts

A framework for real-time and automated monitoring of the condition of culverts based on identifying internal defects via video inspection is developed. Manual inspection using closed-circuit television has several drawbacks, such as inconsistency and subjectivity due to human evaluation. Analysis of digital video, consisting of thousands of megabytes even at lower resolutions, can be laborious and not suited for real-time implementation. An innovative approach is to extract image frames judiciously from the video and analyze frames to locate and categorize major defects. Rather than analyze all extracted frames, one can skip consecutive frames at a minimal loss of accuracy and bring considerable savings in memory and system requirements. Each frame is preprocessed to enhance contrast, through use of an adaptive scheme, and to reduce dimensionality in pixel-space by implemention of region-based processing. Preprocessing is followed by a two-step image segmentation process, which implements a background elimination procedure in the first step and shape detection in the second step. Fuzzy clustering is used as the underlying segmentation model. Defect shape and depth information after post-processing are used as input to an assessment methodology for automated condition state. A simple formulation based on both the damage area and depth is then used to assess the condition of culverts based on a four-point condition assessment scale. The proposed framework is demonstrated with a test example. Future research would entail consolidating the concept by extensive testing and integration for real-time application.

Framework for inspection, maintenance, and replacement of corrugated steel culvert pipes

A framework for inspection, rehabilitation, and replacement of corrugated steel culvert pipes (CSCP) is developed. It is expected to lead to developing a culvert information management system (CIMS), wherein justification and need are based on recent Governmental Accounting Standards Board (GASB) requirements. The CIMS will assist in evaluating infrastructure assets and facilitate comparing present costs of preserving infrastructure. Benefits include long-term savings from adopting optimized preventive maintenance strategies. CSCP condition states are used to express the extent of deterioration. Rehabilitation options and recommendations are given for deteriorated CSCPs. These options will be incorporated into the proposed CIMS, which uses survival probabilities based on the CSCP condition state during the previous year. Survival probabilities within Condition States 1, 2, and 3 are computed on the basis of corrosion research data. However, implementing the proposed CIMS requires field data for CSCPs or l...

Culvert Information Management System

A pilot scale culvert information management system (CIMS) was developed for the New Jersey Department of Transportation to comply with requirements stipulated by the Governmental Accounting Standards Board, GASB-34, and new federal stormwater regulations. The condition states of culverts are used to express the extent of their deterioration and survival probabilities. A financial analysis model was developed on the basis of the remaining value of culverts and the user cost of failures. Different rehabilitation options were discussed, and recommendations were made for deteriorated culverts on the basis of financial analysis. The pilot CIMS can analyze prescribed culvert information and make decisions to inspect, rehabilitate, or replace culverts or to do nothing at project and network levels. At the project level, this is achieved by comparing inspection, rehabilitation, or replacement costs with risks and costs associated with failure. At the network level, the associated costs are optimized to meet annual maintenance budget allocations by prioritizing culverts needing inspection and rehabilitation or replacement. The CIMS has three major computer software components: databases, user interfaces, and functionality modules. Modules include inlet–outlet structures, culvert segments, culvert assessment, and optimization. Users are able to retrieve culvert and inlet–outlet structure physical and financial information and to generate reports vis-à-vis location, road, and milepost for condition state and assets needing immediate repair. The CIMS will also do the following operations: maintain an up-to-date inventory of eligible infrastructure assets; perform maintenance of eligible infrastructure assets for a given budget using a replicable basis of measurement and measurement scale; and summarize results, noting any factors that may influence trends in the information reported.

A conceptual framework for intelligent monitoring systems

This paper discusses the conceptual development of a continuously monitored intelligent system for underground infrastructure. The proposed sensors are based on advanced coupling and refinement of several technologies: electrically conducting composite pipe (ECCP), electrochemical impedance spectroscopy (EIS) and time domain reflectometry (TDR). A significant benefit gleaned from the combination of these technologies is that the resulting system may be used on non-metallic, as well as, metallic pipes. In addition, the synergism of the technologies obtains the maximum information regarding defect location and characterization. The monitoring signal, waveguides, and damage sensor are also discussed, as well as, the data fusion, dynamic modeling and simulation requirements for the intelligent monitoring system.

Intelligent systems for conveyance and storage infrastructure

The objectives of this research project are to identify, demonstrate, and validate intelligent systems for conveyance and storage infrastructure that will enable effective, affordable, real-time, remote measurement, analysis, and reporting of their structural health. Specifically, the project involves testing and validating smart pipes, which could indicate locations of structurally weak areas, i.e., where leaks are likely to occur, and the location of existing leaks for corrective action. During the initial phase of this project an extensive literature search was conducted to identify technologies that could potentially be used in intelligent systems. Although the search was primarily focused on new emerging smart technologies, consideration was also given to innovative uses of established structural monitoring or testing technologies. Four emerging technologies that can potentially locate structurally weak areas and predict incipient leaks were identified: electrically conducting composite pipes, electrochemistry-based corrosion sensors, instrumented cathodic protection, and distributed piezoelectric sensors. Also identified was an innovative use of acoustic emission techniques to track deterioration in pre-stressed concrete pipes by monitoring energy releases from breaking corroded pre-stressing wires. A review of each of these technologies is presented. During the next phase of the program one or more of these technologies will be tested and evaluated further.