الفهرس 
Techniques For Measuring Structural DeformationOnly 14 pages are availabe for public view
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Abstract
The continuous and obvious development in the field of construction nowadays in Egypt like high rise buildings, different structures, dams, towers and different plants as petrol plants make us in a very need of finding suitable and new surveying techniques to measure and monitor any horizontal and vertical displacements or deformations expected in these sensitive and valuable structures and building as well as spatial deformations. Any distortion, movement or deformation in any element of the structure greater than the allowable values may cause damage to the structure and make negative effects. Therefore these structural deformations must be measured and monitored during and after construction by using new precise techniques which will be assessed here in this study compared to precise traditional techniques and studying the applicability and feasibility and accuracy and suitability of these techniques in various engineering projects to validate it for the sake of human safety as well as economic considerations.
Such deformations constitute some problems from the structural point of view. Thus, it is necessary to measure and monitor such deformations before the repair stage; during the repair and after finishing the repair. This is essential to avoid any undesirable consequences that may happen and cause disaster risks of any part of the monument with time.The insurance of the safety of such huge engineering constructions against any human or non-human hazards caused by any shortcoming in detecting and remedy of any expected deformations or damages has been the basic motivation behind under taking the present investigation.
The methods used for monitoring deformations may be generally classified as surveying methods and non-surveying methods and the surveying methods is classified as traditional and new. selecting the method of measurements depends upon the accuracy requirements. This, in turn, is determined by the purpose of the measurements and by the magnitude and direction of the expected deformations or movements.
Hence, the main objective of the current research is to study the practical feasibility, applicability, and accuracy of using some new precise surveying techniques for measuring and monitoring the deformations of structure and compare it with traditional techniques.The thesis analysis is divided into three parts. The first one is a comparison between traditional techniques and GPS in measuring horizontal deformation, the second one is the comparison between the traditional techniques and GPS in measuring vertical deformation, and the third one is comparison between total station and laser scanners in measuring spatial deformation and the best accuracy in transformation methods between the two systems.
The first part is to compare between the use of traditional techniques as vernier scale and new surveying techniques as GPS relative positioning method in measuring and monitoring horizontal structural deformation and what is the applicability and suitability and feasibility and accuracy of using GPS in measuring and monitoring of horizontal structural deformation in various projects.
The second part is to compare between the use of traditional techniques as precise level and new surveying techniques as GPS relative positioning method in measuring and monitoring vertical structural deformation and what is the applicability and suitability and feasibility and accuracy of GPS in measuring vertical structural deformations in various projects.
The third part is to compare between the use of some new surveying techniques which are laser scanners and total stations in measuring horizontal and vertical positioning and spatial distances and the assessment of the transformations methods from a system to another from the point view of its accuracy.
The accuracy of GPS method in measuring and monitoring horizontal and vertical deformations was concluded and it was about 0.3mm in horizontal and 4.85mm in vertical where we can use it in measuring deformation in concrete bridges for horizontal deformation and steel bridges for vertical deformation.
The accuracy of point position (3D) surveyed by laser scanner in raw data compared to total station are 11 mm in X-direction (horizontal direction of the façade), and 7 mm in Z-direction (vertical direction of the façade, and 17 mm in Y-direction (perpendicular direction of the façade) as well as 18 mm in space position. Polynomial transformation is the best approach for transformation from laser data to total station data where it increases the accuracy of results.