Modeling Terrestrial Laser Scanner Data for Precise Structural Deformation Measurement
Publication: Journal of Surveying Engineering
Volume 133, Issue 2
Abstract
A modeling strategy has been developed that permits coarse-precision terrestrial laser scanner observations to be used to accurately measure vertical deflections of deforming beams. The model is developed from fundamental beam-deflection equations and implemented using a weighted-constraint, least-squares curve-fitting approach. After the solution is computed, a statistical testing procedure is applied to assess the level of contribution of each of the estimated parameters in the model and identify redundant terms for removal. Two terrestrial laser scanners (TLSs) are employed to test the approach by measuring the vertical displacement of beams undergoing controlled loading for which the magnitude of displacements was at the level. Results demonstrate that the modeled TLS data, when compared to conventional monitoring equipment, such as convergent digital photogrammetry and contact sensors, achieved an accuracy that is up to 20 times higher than the TLS’s coordinate precision, thus underscoring the benefits of modeling raw point data for precise surface representation. It is shown that one brand of TLS (coordinate precision of ) reliably measured the vertical displacements with an accuracy of (both ).
Get full access to this article
View all available purchase options and get full access to this article.
Acknowledgments
The writers wish to thank McMullen Nolan and Partners Surveyors Pty. Ltd. for the use of their Cyra Cyrax 2500 and Dr. Ian Chandler from the Department of Civil Engineering at Curtin University of Technology for organizing the load tests.
References
Beer, F. P., and Johnston, E. R. (1992). Mechanics of materials, McGraw-Hill, New York.
Clarke, T. A., and Robson, S. (1993). “Building a digital close range three dimensional measuring system for less than £5000.” Photogramm. Rec., 14(82), 675–680.
Fraser, C. S. (1992). “Photogrammetric measurement to one part in a million.” Photogramm. Eng. Remote Sens., 58(3), 305–310.
Fraser, C. S. (1997). “Digital camera self-calibration.” ISPRS J. Photogramm. Remote Sens., 52(4), 149–159.
Fraser, C. S., and Edmundson, K. L. (2000). “Design and implementation of a computational processing system for off-line digital close-range photogrammetry.” ISPRS J. Photogramm. Remote Sens., 55(2), 94–104.
Fraser, C. S., and Riedel, B. (2000). “Monitoring the thermal deformation of steel beams via vision metrology.” ISPRS J. Photogramm. Remote Sens., 55(4), 268–276.
Gordon, S. J., Lichti, D. D., and Stewart, M. P. (2003). “Structural deformation measurement using terrestrial laser scanners.” Proc., 11th Int. FIG Symp. on Deformation Measurements, S. C. Stiros and S. Pytharouli, eds., Publication No. 2, Geodesy and Geodetic Application Laboratory, Dept. of Civil Engineering, Patras Univ., Patras, Greece, 8.
Jacobsen, K. (1982). “Attempt at obtaining the best possible accuracy in bundle block adjustments.” Photogrammetria, 37(6), 219–235.
Leica Geosystems. (2005). “HDS2500 description.” Leica Geosystems, ⟨http://hds.leica-geosystems.com/products/HDS2500_description.html⟩ (January 13, 2005).
Riegl. (2005). “3D imaging sensor LMS-Z210i.” Riegl, ⟨http://www.riegl.com/terrestrial_scanners/lms-z210i_/210i_all.htm⟩ (January 13, 2005).
Stanton, J. F., Eberhard, M. O., and Barr, P. J. (2003). “A weight-stretched-wire system for monitoring deflections.” Eng. Struct., 25(3), 347–357.
Wetherill, G. B. (1986). Regression analysis with applications, Chapman and Hall, London.
Whiteman, T., Lichti, D. D., and Chandler, I. (2002). “Measurement of deflections in concrete beams by close-range digital photogrammetry.” Proc., Joint Int. Symp. on Geospatial Theory, Processing and Applications (CD-ROM), 9.
Zhong, D. (1997). “Robust estimation and optimal selection of polynomial parameters for the interpolation of GPS geoid heights.” J. Geodesy, 71(9), 552–561.
Information & Authors
Information
Published In
Copyright
© 2007 ASCE.
History
Received: Jan 24, 2005
Accepted: Jun 9, 2005
Published online: May 1, 2007
Published in print: May 2007
Authors
Metrics & Citations
Metrics
Citations
Download citation
If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download.