The Information System for Bridge Networks Condition Monitoring and Prediction

Author(s):  
Khalid Aboura ◽  
Bijan Samali

This paper introduces an information system for estimating lifetime characteristics of elements of bridges and predicting the future conditions of networks of bridges. The Information System for Bridge Networks Condition Monitoring and Prediction was developed for the Roads and Traffic Authority of the state of New South Wales, Australia. The conceptual departure from the standard bridge management systems is the use of a novel stochastic process built out of the gamma process. The statistical model was designed for the estimation of infrastructure lifetime, based on the analysis of more than 15 years of bridge inspection data. The predictive curve provides a coherent mathematical model for conducting target level constrained and funding based maintenance optimization.

Author(s):  
Jaakko I. Dietrich ◽  
Mikko A. Inkala ◽  
Vesa J. Männistö

Reliable data on the condition of bridge networks are critical for successful bridge management. However, little attention has been paid to the quality of the data gathered in bridge inspections. This paper reviews the most important areas of bridge inspection that cause variation in bridge condition data and presents possible misjudgments made as a result of poor inspection data quality. The main elements of the inspection quality management system adopted in the Finnish Road Administration are presented, and the development of the quality of inspection data in 2002 and 2003 is briefly summarized. The evidence shows that the quality of inspection data has improved considerably but that the current quality level is not yet sufficient. The quality control system could be improved by increasing inspector interaction during control inspections, using an independent consultant in inspection quality measurements and inspector training, increasing the number of quality measurements, and introducing quality targets.


Author(s):  
David V. Jáuregui ◽  
Kenneth R. White

The innovative use of QuickTime Virtual Reality (QTVR) and panoramic image–creation utilities for recording field observations and measurements during routine bridge inspections is reported. A virtual reality approach provides the ability to document a bridge’s physical condition by using different media types at a significantly higher level of detail than is possible in a written bridge inspection report. Digitally recorded data can be stored on compact disc for easy access before, during, or after an inspection. The development of a QTVR bridge record consists of four major steps: selection of the camera stations, acquisition of the digital images, creation of cylindrical or cubic panoramas, and rendering of the QTVR file. Specific details related to these steps are provided, as applied to various bridge inspection projects. The potential impact of QTVR on bridge management—in which routine inspection data are a factor in making decisions regarding the future maintenance, rehabilitation, or replacement of a bridge—is discussed.


Author(s):  
Glenn A. Washer ◽  
Mohammad M. Hammed ◽  
Paul Jensen ◽  
Robert J. Connor

Bridge inspection results provide input for several important functions such as maintenance, repair, and rehabilitation, bridge load capacity ratings, truck load routing/permitting, and future safety/condition predictions. As a result, the quality and reliability of inspection data are important for bridge management and to ensure the safety and serviceability of bridges. Element-level data collection has been required nationwide for bridges on the National Highway System since 2014, and therefore is relatively new to some bridge owners. The objective of the research reported here was to assess the quality of element-level bridge inspection data by comparing bridge inspection results between different bridge inspectors assessing the same bridges. This paper reports results from two research studies completed to collect data on the quality (i.e., variability) of element-level inspection data. Results of field trials indicated that there was significant variability in the data for bridge elements reported in the study. Based on these data, the element-level inspection results were widely dispersed—the smallest coefficient of variation calculated from the current studies was 18%, but typical values were found to be greater than 50% in most cases, and often greater than 100%. These data provide examples from a series of field trials that illustrate the need for improving the quality of element-level inspections to ensure the reliability of the data provided.


Author(s):  
Ahmed M. Abdelmaksoud ◽  
Tracy C. Becker ◽  
Georgios P. Balomenos

<p>Bridge inspection is essential for sustaining safe and well-performing transportation networks. The Ministry of Transportation of Ontario (MTO) bi-yearly inspects over 2800 bridges in Ontario, Canada. Then assigns each bridge a Bridge Condition Index (BCI) representing its performance level and required rehabilitation<span>. </span>As this is a time and resources consuming practice, this study explores the BCI trends which can allow a better control on inspection and maintenance scheduling. First, statistical analysis is conducted to identify the correlation of the bridge parameters with the BCI. The analysis reveals that the main parameters associated with BCI are bridge age, and time since last major and minor maintenances. Then, multivariate regression analysis is performed to establish a BCI prediction equation function of these parameters. The proposed framework can supplement existing practices for smarter inspection and maintenance scheduling.</p>


2018 ◽  
Vol 18 (08) ◽  
pp. 1840011 ◽  
Author(s):  
Maria Rashidi ◽  
Chunwei Zhang ◽  
Maryam Ghodrat ◽  
Shaun Kempton ◽  
Bijan Samali ◽  
...  

Movement of bridge abutment is a significant issue affecting the overall reliability and safety of the structure. However, despite considerable consequences, potential movement of abutment is usually not considered in design of bridges for serviceability and abutments are generally designed as fixed elements. Theoretical analysis of bridge abutment and deck design provides background knowledge of reactions that should be anticipated and accounted for. Case studies of bridges experiencing movements and rotations show that practical outcomes often deviate from theoretical expectations. The research presented in this paper, aims to develop a better understanding of abutment stability from both a design and maintenance point of view. This paper includes an in-depth case study of the Kanahooka Road Overbridge in New South Wales, Australia. The results of a full bridge inspection leading to identification of multiple serviceability issues caused by movement of abutments are presented. Moreover, a systematic methodology is implemented, to identify potential remedial options for treatment of abutment movement. The knowledge gained through this case study has led to the development of a model for the management of abutment movement.


1973 ◽  
Vol 13 (62) ◽  
pp. 259 ◽  
Author(s):  
H Brownlee

During an experiment conducted for eighteen months at Condobolin, New South Wales, the production and persistence of dryland lucerne grazed by Merino wethers at 10 ha-1 yr-1 were measured under set stocking and three rotational grazing treatments differing in length of spelling period between grazings (grazed one week in four, six or eight weeks). The results showed that although dry matter availability and lucerne survival increased with decreased grazing frequency, only 35 per cent of the lucerne survived in the treatment with the slowest rotation.


2006 ◽  
Vol 46 (7) ◽  
pp. 845 ◽  
Author(s):  
K. Behrendt ◽  
O. Cacho ◽  
J. M. Scott ◽  
R. Jones

Pasture improvement is a well-established technology for increasing production in extensive livestock grazing industries by changing pasture composition and increasing soil fertility. The Cicerone Project farmlets located at Chiswick Research Station, near Armidale in New South Wales, are providing valuable information at a credible scale on the response to 3 different management systems varying in levels of inputs and grazing management. The purpose of this paper is to outline a methodology for assessing farmlet performance in such studies. The assessment focuses on the stochastic efficiency of the different treatments. The impact of pasture persistence, climatic risk, and stochastic commodity prices on optimal rates of farm development are explored by using preliminary data from the Cicerone farmlets to calibrate the GrassGro model. The farmlets modelled represent 2 technology packages. One is a moderate-input package and the other is a high-input package. Preliminary analysis indicates that direct comparison of the 2 farmlets may produce the wrong assessment, because 1 farmlet is operating at a suboptimal level of efficiency in a stochastic sense. This means that direct comparisons of technologies based on the field data may be biased as the technologies should be evaluated at the risk-efficient frontier. The concept of a risk efficient frontier is explained and applied to aid in identifying the trade-offs between profit and risk, and identify differences in the efficiency of the 2 farmlets.


1998 ◽  
Vol 20 (1) ◽  
pp. 26 ◽  
Author(s):  
DB Gardiner ◽  
GJ Tupper ◽  
GS Dundeon

Landsat Multispectral Scanner (MSS) digital imagery was used to estimate the distribution, density and change in woody shrub cover over time in western New South Wales. The purpose of the project was to derive maps of woody cover which can be used as a basis for regional planning and property planning. Assessment of woody vegetation cover using satellite imagery enables regions which are more susceptible to shrub encroachment to be targeted for control strategies. Dry season images which had minimal green vegetation were used, because the spectral signatures of scrubby ground cover interfered with the proper classification of woody vegetation. For each region, multidate imagery was classified using a pixel unmixing algorithm to derive data sets which showed woody canopy cover. These data were then rescaled to percentage values using aerial photography sampled throughout each region. A geographic information system (GIS) was used to derive changes in woody cover between both dates and to present the data in map form. Most current woody cover in the study area occurs at less than 20% cover, whilst higher levels (40 to 80%) occur in the eastern parts of the Louth and Barnato regions. At least 20,3 10 km2 of the 120,000 km2 study area is already affected by woody vegetation cover levels of greater than 40%, which significantly reduces carrying capacity and pastoral productivity. Changes in woody cover over a 10 to 20 year period were varied. Approximately 24% (26,041 km2) was relatively stable, whilst 20% of the Barnato region had moderate decreases (1 1 to 30%) due to wildfires, and increases of 11 to 30% cover occurred on 'hard red' soils in the east. Emerging woody vegetation of less than 10% cover occurred over 1816 km2 of Sandplains and Stony Lowlands in the Louth and Barnato regions, whilst woody vegetation levels of more than 40% cover occurred in the Barnato region. Considerable 'infilling' of previously unwooded areas was noted for regions which already had high levels of woody cover. A minimal amount of prescribed clearing was apparent from the change data, which suggests that effective control of shrubs is difficult to achieve and that future scenarios will see continued encroachment. The findings suggest that the southern Louth and Barnato regions are most at risk of further shrub encroachment, and that these areas need to be targeted for shrub control. The data provide a quantitative estimate of woody shrub cover which is useful for economic assessments, as well as providing an information base upon which woody shrub management strategies can be developed. Key words: Landsat Multispectral Scanner, remote sensing, geographic information system, change detection, rangeland, monitoring, land cover.


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