AP22688230 "Design Realtime Building Foundation performance monitoring systems using distributed fibre-optic sensors from construction to in-service stage"
Supervisor: PhD Buranbayeva Aigerim
Relevance:
Data collection in structural health monitoring involves the selection of the type of sensors to be used, their location, the number of sensors to be used, and the equipment to collect, store, and transmit the data. One of the most important aspects is the frequency of data collection. Since the data can be measured under different conditions, the ability to normalize the data becomes very important to the structural health monitoring system process. The peculiarities of high-rise buildings place increased demands on the results of geotechnical engineering surveys and should address the following main tasks in their performance:
- study of the geological structure of the soil massif of large volumes (up to 60 m in depth and not less than 2 foundation widths beyond its contour);
- reliable assessment of hydrogeological and hydrochemical conditions of the compressible soil massif, as well as in the excavation zone and in the adjacent territory with the establishment of their corrosive aggressiveness, in time;
- determination of deformation and strength properties of dispersed and rocky soils at large ranges of stress changes;
- instrumental observations and monitoring of deformations of the foundation base and adjacent territory under static impacts.
The main problem to date is the lack of generally applicable sensors for direct monitoring of deformation in real conditions. Although some variants exist, they are limited to very specific applications and cannot be generalized.
Recently, fiber optic sensors for civil engineering are becoming more and more common. Their advantages are small size, good resolution and accuracy, as well as excellent ability to transmit the signal over long distances. This is especially true for the construction of high-rise buildings, an example of which monitoring is presented in this paper. In many cases, data fusion is performed in a simple way, such as when the relative information between different sensors is considered to obtain the mode shape. In other cases, complex analysis of information from sensor arrays is performed, e.g., using artificial neural networks. We propose a system that allows obtaining relevant data from sensors for monitoring for many years, which will allow timely detection of damage in the structures of the object, to make quick decisions, which in turn can significantly reduce the cost of repair of buildings and structures and will increase the safety of operation. It is also important that the state pays great attention to safety in the construction of unique facilities, and safety is achieved only through control and monitoring, and the introduction of such a system and its operation for many years can significantly reduce the burden on the state budget.
Scientific novelty of the project is substantiated by:
- scientific and technological support for a new methodology of foundation slab monitoring using fiberoptic sensors;
- a new proposed sensor system to improve the process of visualization and analysis of structural health monitoring, in addition to the operational safety of the building;
- recommendations for basic or structural analysis.
Target:
Development of an innovative system for monitoring the load-bearing structure of buildings and structures using distributed fiber optic strain sensing of foundations, which allows:
- carry out continuous monitoring of the structure of buildings and structures to avoid cracks in the foundation slab and negative consequences in the operation of the building, and thus increase the reliability and safety of the project due to the timely detection of critical points of deformation;
- receive data from sensors with integration into the system for real-time interpretation of results.
Expectation:
The main results of the work include the development of a real-time monitoring system for building foundations using distributed fiber optic sensors from the construction phase to operation. To achieve the results, the following tasks will be accomplished;
˗ existing methods in the field of structural monitoring of buildings and structures be studied;
˗ numerical analysis of slab expansion be performed to determine the minimum track length for fiber-optic sensor cable;
˗ be performed modeling of concrete raft to determine vertical and horizontal displacements using Plaxis/Midas software;
˗ be developed a distributed fiber-optic sensor system on the concrete slab surface for comparative analysis;
˗ will be conducted tests for data collection and processing at the construction site;
˗ be justified the obtained deformations during fiber optic monitoring for interpretation of results;
˗ be interpreted the results for prediction and decision making in a real-time information system;
˗ recommendations for basic structural analysis and detailed structural analysis with the use of fiber-optic sensors, as well as scientific and theoretical conclusions will be developed in the proceedings of international conferences and in 2 articles in journals from the first three quartiles of the impact factor in the Web of Science database or having a CiteScore percentile in the Scopus database of at least 50;
˗ be issued a patent by filing a patent application with the National Institute of Intellectual Property of the Republic of Kazakhstan (www.kazpatent.kz) or near/far abroad.
Result:
Recommendations for basic structural analysis and detailed structural analysis with the use of fiber-optic sensors, as well as scientific and theoretical conclusions will be developed in the proceedings of international conferences and in 2 articles in journals from the first three quartiles of the impact factor in the Web of Science database or having a CiteScore percentile in the Scopus database of at least 50;