What is Precise Engineering Survey? Application of Precisely Engineering Survey
What is Precise Engineering Survey?
Precise engineering survey is the process of accurately measuring and recording the position of natural or man-made features on the earth’s surface. It is used in engineering, surveying, and navigation, mapping, and construction projects.
The purpose of a precise engineering survey is to establish a control point or reference system that can be used to accurately measure distances and directions between other features.
Precise engineering survey is a process that helps engineers to design and build structures and systems while minimizing waste and errors.
The survey is conducted by engineers who use mathematical models and calculations to identify potential problems and correct them before construction begins.
The Precise Engineering Survey also involves the continuous system for monitoring changes in the condition of concrete structures, such as bridges and roads.
The process involves continuously measuring the elastic and plastic strain within a structural element, which is then used to calculate its condition.
In order to accurately measure the condition of any concrete structure that’s been operating over time, it must be monitored on an ongoing basis.
The process typically involves placing one or two strain gauges at different locations on the structure and then measuring their outputs with an oscillating-type pressure gauge.
Monitoring the structure’s load-bearing capacity is important, because most concrete structures are designed to carry loads in one direction only.
Roads, for example, tend to be built assuming traffic will always be traveling in one direction. As a result, they can become dangerously uneven when subjected to the weight of vehicles traveling in the opposite direction – a risk that increases with age.
But while monitoring can be used to determine if a structure is safe and still usable, it isn’t very precise. That’s where the Precise Engineering Survey comes in.
The system was developed by researchers at the University of Utah, who discovered that measuring changes in a structure’s elastic and plastic strain over time could be used to determine its condition more accurately.
What this means is that determining a structure’s condition with monitoring alone is only an approximate process. It measures age, but doesn’t take into account any specific change in condition over time.
It also doesn’t take into account the responsiveness of a structure to various changes in its load-bearing capacity.
History of Precise Engineering Survey
The Precise Engineering Survey was invented in the 1980s by researchers at the University of Utah.
It has since been used in several instances, including as part of a study that determined the effectiveness of rehabilitation work on a 75-year-old concrete bridge.
The technique was also used to analyze the state of a 40-year-old concrete tunnel.
There are a number of commercial products that perform the same function as the Precise Engineering Survey, including:
- LPS (Life Positioning System),
- SPI (Strain Partitioning Instrument)
- SOS (Shape Operational System).
But while these systems generally operate in much the same way as the Precise Engineering Survey, they only provide measurements, rather than measurement and analysis together
Application of Precisely Engineering Survey
It can be applied in different areas as highlighted below.
- Inspection and Maintenance of Infrastructure investments- The existing deformed bridge inspection methods generally rely on the traditional methods of visual and tactile examination.
As a result, cost and time pressures often result in decisions being made based on inadequate inspection criteria.
The Precise Engineering Survey eliminates this problem through the use of advanced analytical techniques coupled with a conservative evaluation of possible damage to identify problems that in the past were not detected.
- Cracking Evaluations- The direct and indirect costs related to repairing concrete members cracking have become significant.
The Precise Engineering Survey evaluates cracks in a very conservative and useful way using acceptable methods of evaluation.
- Assessment of Structural Integrity- Rather than completely abandon a structure that has reached the end of its useful life, identifying weaknesses that can be corrected with relatively minor repair work can be a cost-effective alternative.
The Precise Engineering Survey method is able to give an accurate diagnosis and provide a cost-effective recommendation for a repair alternative or replacement.
- Planning of Restoration and Rehabilitation- If it’s possible to repair or restore an existing structure, the Precise Engineering Survey can help make this economically feasible by identifying possible failure modes.
In the case of bridges, this can minimize the amount of irreversible damage that may result if some repairs are not carried out correctly.
- Inspection of Unevenness, Flatness and Defects – The typical method of inspecting concrete structures for damage is based on visual and tactile techniques.
The results are often unreliable. The Precise Engineering Survey provides a reliable means of monitoring changes in the structure’s condition.
- Operation and Maintenance decisions – The analysis of the data produced by the Precise Engineering Survey can not only indicate if a structure is safe, but also provide useful information about how to maintain it to ensure safe usage and operation.
- Road Quality Measurement – Nationally, there are more than 1.1 million kilometers of paved roads in the United States. If you include unpaved roads, that length increases to nearly 2.8 million kilometers (1.7 million miles).
This system can be used to accurately measure the condition of concrete roads and other transportation systems, making it easier for government agencies responsible for managing these facilities to protect them from deterioration and to ensure their quality remains high over time.
- Bridge Management – Bridges continue to play a crucial role in commerce and transportation across the United States. The condition of these structures can impact both the public’s perception of a community and the efficient movement of goods and services.
The current methods available for evaluating concrete bridge condition are not very reliable. In some cases, agencies with responsibility for managing these facilities have to resort to visual examination, based on appearance rather than measurement.
This system can provide an affordable, accurate method of assessing the overall condition and performance of bridge decks.
Process of the Precise Engineering Survey
The commonly used procedure for conducting Precise Engineering Survey is:
- Define the structure of to survey.
- Select and apply the appropriate probes to measure the strains at different locations in the structure under loading.
- Record the reading of strain gauges at corresponding locations.
- Take readings of displacement, force, torque, and other load and structure-related variables in each iteration.
- Perform analysis to determine load-carrying capacity and assessment of each structural element and sub-element’s state of health (condition).
- Perform assessment of the structure’s load-carrying capacity and thermal condition by taking readings of displacement, force and torque at different points in the structure.
- Perform analysis of the structure’s load-carrying capacity and thermal condition, where possible.
- Measure strain at various locations in a structural element to determine its relative age.
- Monitor conditioning with daily or weekly or another agreed periodicity
- Make suggestions for further studies to improve condition assessment.
- Inform local agency of any issues and require repairs
- Provide accurate condition assessment for maintenance requirements and rehabilitation programs for the structure.
Precise Engineering Survey Principle
The principle underlying the Precise Engineering Survey involves taking a set of measurements over time and then combining them with model-based calculations to make more accurate predictions about how a structure’s condition is changing.
It’s based on a principle developed by researchers at the University of Utah called “infinite element analysis,” which were originally used to predict structural responses to earthquakes and other natural disasters.
As a result, the Precise Engineering Survey incorporates the use of finite element analysis to determine a structure’s condition over time and then compare those predictions with actual monitored data.
The Precise Engineering Survey Principle is based on developing an understanding of what it means for a structure to remain in constant equilibrium.
To do this, researchers will typically begin by using an analytical model of the structure and performing steady-state analyses to determine how its various components react to various loads over time.
Once a structure’s behavior is well understood, the information can then be used to develop equations that describe how a particular structure responds to changes in its load-bearing capacity.
These equations – in turn – can be used to make more accurate predictions about its condition as time progresses.
Precise Engineering Survey Benefits
Some of the benefits are;
- Better monitoring of concrete structures.
- More accurate data-driven predictions of a structure’s condition.
- Confirmation that a structure has the appropriate load-bearing capacity to remain in an equilibrium state.
- Improved safety of a structure by more accurately predicting its condition over time.
- Defense against lawsuits relating to incidents involving an unsafe concrete structure.
- Reduction of unnecessary maintenance and repair of a bridge or road.
Precise Engineering Survey Practices
Accelerator alignment-rotation test.
This fundamental principle is used to determine the maturation of concrete at different locations within the structure. The test involves applying a force to a structure, recording the deflection.
The sample is then rotated, and the process repeated. By comparing the readings taken from each iteration, it’s possible to determine how its strain has changed over time and thus estimate its relative age.
Solar radiation-temperature decay test.
This test is used to reveal how easily a structure’s condition is influenced by external factors such as solar exposure and temperature.
The test involves taking the temperature of a sample and then gradually increasing that temperature over a period of time.
The readings taken from each iteration are then used to estimate the amount of radiation that has reached a particular location within the structure and thus determine its age.
Industry Measurement-condition prediction.
This test is used to determine the load-carrying capacity of a structure at various locations within it. It involves measuring a structure’s deflection at each location and then performing a calculation to determine its load-carrying capacity.
The analysis is then used to predict the structure’s condition over time, based on whether or not it has been exposed to corrosion.
This test is used to determine the amount of strain that has occurred at various locations within a structure under different thermal conditions.
It involves measuring a structure’s deflection and then performing calculations to determine its elasticity over time.
The analysis is then used to predict the structure’s condition over time, based on the temperature changes it has been exposed to.
High speed railway surveying technology-deflection and rotation measurement.
This test is used to determine the load-carrying capacity of a structure.
It involves measuring a structure’s deflection at various locations and then performing calculations to determine the amount of horizontal force being exerted on it by trains passing through it at different speeds.
The analysis is then used to estimate the structure’s load-carrying capacity and its overall condition at each location, along with their changes over time.
Systems that can be used to monitor Precise Engineering Survey
- Satellite-based systems
A satellite-based system typically involves large telescopic mirrors that are aimed at observing a particular structure, with a camera and other optical components attached to it.
The software calculates images of the structure’s surface, determines its shape using models of various parts of its geometry, and then uses those measurements to make predictions about its condition.
Such systems are typically expensive and limited in the number of structures they can monitor at one time.
- Airplane-based systems
Airplane-based monitoring systems typically involve the use of high-definition cameras, attached to a flying aircraft, that are used to capture images of the structure in question.
The captured images are then used to determine its shape and make predictions about its condition over time.
Such systems can be relatively expensive but allow for more precise measurements than satellite-based monitoring systems.
- Vehicle-based systems
Vehicle-based monitoring systems typically involve the use of specially designed vehicles, mounted with optical or video sensors.
Those sensors are used to capture images of the structure in question and then processed to determine its shape and predict its condition over time.
Such systems are relatively inexpensive but typically offer less precise measurements than satellite-based monitoring systems.
- Ground-based systems
Ground-based monitoring systems typically involve the use of a large vehicle, equipped with optical or video sensors.
Those sensors are used to capture images of the structure in question, and then processed to determine its shape and predict its condition over time.
Such systems can be relatively inexpensive but offer less precise measurements than satellite-based monitoring systems.
- Structural integrity
A structural integrity system is an integrated structure that monitors a particular structure’s condition and performs a prediction.
Most commonly, it involves the use of sensors attached to the structure in question and connected to a computer that performs calculations to determine its overall condition over time.
Such systems are usually inexpensive but do not offer comparisons against other methods of monitoring, so their accuracy cannot be fully evaluated.
How are the measurements from Precise Engineering Survey Systems used?
These measurements are used to determine the structure’s load-carrying capacity and thus its overall condition.
Is there a difference between absolute age and relative age?
The answer depends on the type of sample that is being studied and its location within an object, since different locations can have different ages due to factors such as corrosion failures and other external influences.
How does a Precise Engineering Survey System improve over other methods of surveying?
A Precise Engineering Survey System is able to offer a high degree of accuracy, which cannot be achieved by other methods of surveying such as satellite-based and airborne systems.
How much does a Precise Engineering Survey System cost?
A Precise Engineering Survey System can be used to monitor a number of different structures and has the added benefit of being able to provide a high degree of accuracy, which cannot be achieved by other systems.
How can the accuracy of Precise Engineering Survey Systems be improved?
Precise Engineering Survey Systems are relatively expensive, but it is possible to improve their accuracy by increasing the number of data points that are measured against each other over time.
How long does it take to process and analyze the data from a Precise Engineering Survey System?
The analysis is performed on the system’s calculation engine, which can take around one month to complete.
How accurate are the predictions made by a Precise Engineering Survey System?
This depends on how good the data set and calculations that are used in the system are, since all of them offer a degree of error.
How do Precise Engineering Survey Systems compare to airborne and satellite-based systems?
This depends on the type of data that is being measured, since all three systems are typically capable of providing a high degree of accuracy.
What are some disadvantages of Precise Engineering Survey Systems?
These systems can be quite expensive to install and maintain, as well as require a significant amount of maintenance and recalculation over time.
How can a Precise Engineering Survey System compete with satellite-based systems?
Precise Engineering Survey Systems use data that can be collected with an airplane or vehicle and are able to offer a high degree of accuracy, which is not possible with satellite-based systems.
How long does it take to install a Precise Engineering Survey System?
This depends on the type and location of the structure being monitored, as well as the number of vehicles and other equipment that are required for its installation.
How much time does it take to install a Precise Engineering Survey System?
This depends on the type and location of the structure being monitored, as well as the number of vehicles and other equipment that are required for its installation.
What are some of the most common uses of Precise Engineering Survey Systems?
These systems are used to monitor any structure that can be measured by its shape alone, such as pedestrian bridges and buildings in urban areas