Cables, which represent between 5 and 8% of the investment of a structure, are critical and sensitive elements that need regular monitoring due to stress and exposure. Wire rope and guy-wires hold up critical infrastructures worldwide. From flare stacks, to broadcast towers, transmission towers and more. Many of these wire ropes have not been properly inspected in years due to their height, time it takes to inspect and that manual, visual inspections are not comprehensive and they don’t provide quantitative data or deterioration progression over time.
Manual Inspection vs Robotic Inspection
Despite the fact that the failures of a structural element or a complete structure are rare, they happen to be attributed generally to three causes: pre-existing manufacturing defects, weather and ageing induced deterioration or damage induced during service. The first type of cause results fundamentally from negligence, ignorance or human errors in any of the design, material selection, manufacturing or quality control processes.
In contrast, the second cause of structural failure is the most common. Over time materials break down and age. Combine this with being exposure to the elements and corrosion which occurs in all infrastructure elements and the third which is more difficult to prevent because it occurs due to unknown behaviours or conditions that could not be anticipated or predicted during design.
Infrastructure Inspection Services
Have you ever thought about who decides how to inspect and repair an infrastructure, such as a road or a bridge? The most common is for the most part still the same as it was a hundred years ago, that an operator, on foot, goes down with a notebook notating the deteriorations that he sees and uses these annotations to determine the state of the infrastructure. On many occasions the operators walk along the shoulder, while the traffic circulates normally around them, with the consequent danger both for them and for road users. This task is really monotonous and repetitive, causing visual fatigue in the operators, which makes it difficult for them to obtain acceptable degrees of reliability. Furthermore, although visual inspection when carried out by experienced operators adapts well to new situations, it has a high degree of subjectivity, which means that two different operators, or the same operator on different occasions, offer different results in the same situation. Due to the above, one of the biggest challenges that civil engineers keep encountering is the inspection and maintenance of existing infrastructure to ensure that bridges, roads, pipelines and tunnels continue to provide reliable service in safe conditions.
The application of new technologies to carry out these inspections makes it possible to reduce these risks, obtain objective results, increase the inspection speed, and have this digitized data available. In short, it improves the working conditions of the operators and the quality of the results.
Structural cables (cable-stayed bridges, suspended bridges and decks) are civil engineering structures of complex operation, where the cable-stayed system constitutes an essential element of the structure. To reach the end of their useful life in good condition, the tie rods and their anchors need periodic monitoring, and must also undergo detailed inspections in the event of extreme events: exposure to vehicle fire, shock wave of an explosion, impacts, lightning, storm winds, earthquakes, etc.
Periodic inspection and instrumentation of the cable-stayed system allow us to better understand its behaviour over time, detect possible anomalies and undertake maintenance actions when necessary, before the action of time has a negative effect on the life of the system. In general, it can be said that the most common non-destructive techniques are: visual inspection; ultrasound; eddy currents; magnetic particles and penetrating liquids; of which, although limited because it only allows the identification of superficial defects, typically restricted to a few small areas where an experienced inspector believes may have issues, visual inspection is still the most used of all.
Is this the last vestige of manual services left on the planet. The availability of viable technology to do a more comprehensive inspection exists and yet is not often used. While we won’t go into the the corporate and political reasons, the advanced ageing of much of the worlds infrastructure will soon dictate the adoption of these technologies.
The technical advancement in nondestructive testing technology and advancement in robotics and software make it possible today to conduct more comprehensive inspections than ever before. Lets look at an example.
Cable Stayed Bridge Inspection. The most common practice to inspect a cable stayed bridge is to close a lane on a bridge and park a “crash truck” and bucket truck. The bucket truck is used to send an inspector at height to inspect the HDPE sheathing that surrounds the steel the holds up the bridge. Then how is the steel inspected? In most cases it is not. What is the crash truck for? Traffic crossing the bridge would frequently crash into the bucket truck so a crash truck is used so that a careless driver not expecting an obstruction crossing the bridge can crash into the crash truck and not harm the inspector.
A Better way.
Getting to a solution
Infrastructure around the US and the world continues to deteriorate at an alarming rate. The catastrophe caused by these failures including rising death tolls and loss of economic productivity and GDP for countries around the world. In order to prevent this there are powers at work that would like to see the advancement of inspection methods from manual and subjective to more quantitative with the use of technology. More and more asset and maintenance management as well as construction companies have turned to the robotics industry to solve this problem. With the skilled labour for manual inspections retiring and not enough experience to take its place it is imperative to advance the adoption of technology into one of the last manual industries. Utilizing technology for inspections will improve speed and efficiency, increase job site safety and make better profits. Reducing lane closures will help decrease the amount of lost productivity due to traffic, help get goods to ports and deliveries to their destination on time, increase economic health.
Non-destructive evaluation can be defined as the process of inspection and analysis of a structural component or element to determine its integrity. Thus, non-destructive evaluation not only includes the entire non-destructive inspection process, but also the analysis of the results of this inspection to qualify the structural condition of the evaluated component.
Infrastructure Preservation Corporation (IPC) is a non-destructive testing and robotic engineering company that provides comprehensive condition assessment reports on critical infrastructure assets worldwide. IPC has unparalleled experience in these complex operations. Buy utilizing advanced nondestructive testing technologies and marrying it with robotics and advanced software,
Infrastructure Preservation Corporation
Infrastructure Preservation Corporation has developed inspection services that can provide more quantitative data for asset manager to better manage their inspection and maintenance budgets. The repetitive use of their technology provides a road map for deterioration progression over time saving billions in maintenance repairs and potential catastrophe.
As more of these technologies are adopted to replace the current manual methods, the health of infrastructures will continue to improve, lane closures and heavy equipment will become a thing of the past and the technology will do what it is supposed to do, make better the human condition.
Infrastructure Inspection Blog
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