Measuring techniques of building façades

1. Measuring techniques of building façades Rak-43.3312 Repair Methods of Structures II (4 cr) Esko Sistonen

2. Information is needed: the surface area of the façade to berepaired -the whole façade dimensions, the original drawings (inaccurate or missing) Information about the facade dimensional tolerances, especially important in the repair of the old facade in which it is covered with a cartridge or shell element solution  Tachymeter+ GPS Laser Distance Meter DVP-photogrammetric method (stereo pairs of images)

3. The Use of ICT 3D Measuring Techniques for Visual Inspection of Building Facades KITARA- Rakentamisen laadun parantaminen 3D-mittaustekniikan avulla

4. Background Building envelope Deterioration of building facades Visual inspection Similar laser-scanning research (different fields) Research focus Methodology Some expected results

5. Objective to develop ICT-based tools to automatically retrieve dimensions of factory-made elements and their surface quality as well as deformations after installation and automatic comparison of these variables against 3D CAD models

6. The work consists of the following tasks: 1.To develop methods for analytic and visual inspection of deviations between planned and measured dimensions of component units. 2. To develop methods for verification of the skeletal structure of a building and surface quality of the facade. 3. To identify measuring devices and establish the tolerances for the new up-to-date component technology and to study the propagation of precision through the whole measurement process, considering both instrumental properties and measurement geometry. 4. To improve the measuring process at the construction site. 5. To study the potential of terrestrial laser scanner in construction monitoring. 6. To develope image based methods to extract geometric information from buildings and to create methods to produce image data suitable for CAD-overlaying.

7. Research focus The research will focus on the building envelope facades, windows and outer doors. Brick and concrete wall façades will be investigated. The research doesn’t involve glass or steel facades (future work?).

8. Research procedure Selecting of building facades (concrete and bricks facades) Field work (Laser scanning and tacheometry as reference) Image processing (Scanning software) Model creation (AutoCAD) Database design (include modeling data + photos?) Develop condition surveying methods (feature extraction and inspection of the model)

9. Building envelope

10. Deterioration of building facades Spalling of concrete cover due to corrosion Cracking of concrete panels Frost damage Bending of concrete panels due to frost action

11. Deformations and bending of concrete elements Delamination of bricks and rendering coatings Windows and doors cracks and paints etc (?) Reconstitution (interpretation) of building facades and balconies (comparing to original drawings) Visual inspection of building facades

12. Literature review Road surface texture inspection using high resolution Transverse profile measurements C. MAYS et al 2006, Phoenix Scientific Inc.

13. Literature review Feature Extraction And Modeling Of Urban Building From Vehicle-Borne Laser Scanning Data B.J. Li, 2004 Hong Kong, China DoPP = Density of Projected points

14. Literature review Deformation Measurement using Terrestrial Laser Scanning at the Hydropower Station of Gabčíkovo Thomas SCHÄFER, 2004 Slovakia

15. Selecting building facades

16. Selecting building facades Raiviosuonmäki 7, Vantaa. Kohteessa on kaksi rakennusta 5- ja 4-kerrosta

17. Scanning FARO LS 880 laser scanner. www.faro.com The tacheometer Leica TCA2003

18. Potential research idea • Current methods for evaluating earthquake damage for load bearing structures are visual • Laser scanning is a potential measurement method for forming a database of load bearing structures of important buildings, like airports, train stations, governmental buildings etc. • Quick scanning of damage after earthquake secure the safety of buildings & people Before earthquake After earthquake

19. Results Examples from the literature review

20. Results Examples from the literature review (quality control in the metal industry using laser scanning)

21. Detecting the Deterioration of Building Facades Using Terrestrial Laser Scanning Technique Field measurements (TLS & Tachymeter) Bowing of marble cladding building facades Crack in the building facade footing The surface structure of the marble panel

22. Bowing Potential Test

23. Bow-meter

24. Field measurements (LTS & Tachymeter)

25. Anna Erving

26. Building Quality KITARA- Rakentamisen laadun parantaminen 3D-mittaustekniikan avulla 20.3.2007

27. Building Quality KITARA- Rakentamisen laadun parantaminen 3D-mittaustekniikan avulla

28. Building Quality KITARA- Rakentamisen laadun parantaminen 3D-mittaustekniikan avulla

29. Building Quality KITARA- Rakentamisen laadun parantaminen 3D-mittaustekniikan avulla

30. Antero Kukko

31. Crack in the building facade footing Nina Heiska KITARA- Rakentamisen laadun parantaminen 3D-mittaustekniikan avulla

32. The surface structure of the marble panel Antero Kukko

33. Conclusions • Laser scanning is a new technology for acquiring building facade data in three dimensions with high accuracy and low processing time. • The rapid collection of 3D information serves several purposes including historical documentation, building condition documentation, construction as-built development, and BIM development. • The result will be: • Methods to automatically extract geometric information from laser scanner data • CAD-tools for analytical and visual monitoring of the building condition • laser scanner instrumental and methodological errors!!

34. Conclusions 3D laser scanning has become an emergingly prominent vehicle for acquiring building spatial data in three dimensions with high fidelity and low processing time. The rapid collection of 3D information serves several purposes across GSA business lines, including historical documentation, facility condition documentation, construction as-built development, and BIM development.

35. Concrete Solutions 20093rd International Conference on Concrete RepairVenice/Padova, Italy29 June-2 July 2009. The potential of terrestrial laser scanning for detecting the deterioration of building facades

36. Outline of the presentation Introduction • Introduction • Research project • Laser scanning • Building facades inspection • Field measurements • Results • Conclusions • Future work Field measurements Results Conclusions Future work Page 36

37. Research project Introduction • This paper is a part of the research project: “Use of ICT 3D measuring techniques for high quality construction” • Research group: • Structural Engineering and Building Technology, TKK: Fahim Al-Neshawy; Susanna Peltola; Jukka Piironen and Prof. Jari Puttonen • Institute of Photogrammetry and Remote Sensing, TKK: Anna Erving; Nina Heiska; Pano Salo and Milka Nuikka • Finnish Geodetic Institute: Antero Kukko Field measurements Results Conclusions Future work Page 37

38. How laser scanning works • Laser scanners use either the Time-of-Flight (TOF) measurement method or phase-based measurement to obtain target point distance. • Time-of-Flight measurement is based upon the principle of sending out a laser pulse and observing the time taken for the pulse to reflect from an object and return to the instrument. • Advanced high-speed electronics are used to measure the small time difference and compute the distance range to the target. • The distance range is combined with high resolution angular encoder measurements to provide the three-dimensional (X,Y,Z) location of a point. • Laser scanner is capable of measuring up to 50,000 distances per second. Introduction Field measurements Results Conclusions Future work Page 38

39. Laser scanning data processing Raw observations collected by the scanner Introduction Field measurements Raw XYZ formatting and exporting the raw data into raw XYZ data from the scanning system Results Aligned XYZ determined by processing third-party software Conclusions Future work Processed model is the basis for the interpretation and decision making Page 39

40. Laser scanning for building facades inspection Introduction Field measurements Results Conclusions • Examples: • Deformations and bending of concrete elements • Delamination of bricks and rendering coatings • Reconstruction of building facades drawings (comparing to original drawings) Future work Page 40

41. Field measurements Introduction Field measurements Results FARO LS 880HE80 terrestrial laser scanning system Leica TCA2003 tachymeter Sketch of the bow-meter and the location of the measuring points on the marble panel. Conclusions Future work Measurement distance to the façade • 4.5 m to the center of the facade • About 5 m to the corners Page 41

42. Bowing of marble panels Introduction Field measurements Results Conclusions Future work Terrestrial laser scanning data, colored by the magnitude of the deformation in meters from the planarity. Page 42

43. Bowing of marble panels Introduction • The bowing of marble panels was calculated according the following formula: • where B is the bowing magnitude (mm/m) d is the measured value of bowing (mmL is the measuring distance between the supports of the marble panel in (mm). • The bowing of the convex and concave marble panels was calculated by fitting a second order curve to the laser scanning point cloud data from the centre line of the panel both in the vertical and the horizontal direction. Field measurements Results Conclusions Future work Page 43

44. Bowing of marble panels: examples Introduction Field measurements Results Conclusions Future work Page 44

45. Bowing of marble panels Introduction Field measurements Results Conclusions Future work Results of measurements carried out on the marble facade using terrestrial laser scanning system tachymeter and bow-meter Page 45

46. Surface delamination of bricks Introduction Field measurements Results Conclusions Aligned XYZGeoMagic studio software Future work Page 46

47. Surface delamination of bricks Introduction • Example of the delamination of bricks and the deterioration of joints detected from the laser scanning data. • The maximum delamination of the bricks (red colour) was about 10 mm from the outer surface. • The depth of the weathered plaster of the joint is about 10 mm. Field measurements Results Conclusions Future work Page 47

48. Reconstruction of building facades drawings Introduction Field measurements Results Conclusions Future work Page 48

49. Conclusions Introduction • Laser scanning is not a replacement for existing condition survey techniques, but an alternative , which provides location based information on the building defects and deterioration • Terrestrial laser scanning technique gives a reasonable method for measuring the bowing of marble and many other kinds of cladding panels • The extracting of the deterioration features of building facades like surface delamination of bricks and joint failures can be performed from the laser scanning data • Due to large amount of three dimensional data, efficient computing and analysis tools are needed to be developed and tested Field measurements Results Conclusions Future work Page 49

50. Future work: 4D concept Introduction Field measurements Time (years) Results Conclusions Analysis Laser scanning Automatic evaluation of the condition of the structure Condition surveydatabase Future work Photogrammetry Visual inspection Measurement technology (Real world) Page 50