Presentation on theme: "Measuring techniques of building façades"— Presentation transcript:
1Measuring techniques of building façades Rak Repair Methods of Structures II (4 cr)Esko Sistonen
2Information 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+ GPSLaser Distance MeterDVP-photogrammetric method (stereo pairs of images)
3KITARA- Rakentamisen laadun parantaminen 3D-mittaustekniikan avulla The Use of ICT 3D Measuring Techniques for Visual Inspection of Building FacadesKITARA- Rakentamisen laadun parantaminen3D-mittaustekniikan avulla
4Background Research focus Methodology Some expected results Building envelopeDeterioration of building facadesVisual inspectionSimilar laser-scanning research (different fields)Research focusMethodologySome expected results
5Objectiveto 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
6The 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.
7Research focusThe 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?).
8Research procedureSelecting 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)
10Deterioration of building facades Spalling of concrete cover due to corrosionCracking of concrete panelsFrost damageBending of concrete panels due to frost action
11Visual inspection of building facades Deformations and bending of concrete elementsDelamination of bricks and rendering coatingsWindows and doors cracks and paints etc (?)Reconstitution (interpretation) of building facades and balconies (comparing to original drawings)
12Literature reviewRoad surface texture inspection using high resolutionTransverse profile measurementsC. MAYS et al 2006,Phoenix Scientific Inc.
13Feature Extraction And Modeling Of Urban Building From Vehicle-Borne Laser Scanning Data B.J. Li, 2004 Hong Kong, ChinaLiterature reviewDoPP = Density of Projected points
14Literature reviewDeformation Measurement using Terrestrial Laser Scanningat the Hydropower Station of GabčíkovoThomas SCHÄFER, 2004Slovakia
16Selecting building facades Raiviosuonmäki 7, Vantaa. Kohteessa on kaksi rakennusta 5- ja 4-kerrosta
17Scanning FARO LS 880 laser scanner. www.faro.com The tacheometer Leica TCA2003
18Potential research idea Current methods for evaluating earthquake damage for load bearing structures are visualLaser 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 & peopleBefore earthquakeAfter earthquake
20ResultsExamples from the literature review (quality control in the metal industry using laser scanning)
21Detecting the Deterioration of Building Facades Using Terrestrial Laser Scanning Technique Field measurements (TLS & Tachymeter)Bowing of marble cladding building facadesCrack in the building facade footingThe surface structure of the marble panel
31Crack in the building facade footing Nina HeiskaKITARA- Rakentamisen laadun parantaminen 3D-mittaustekniikan avulla
32The surface structure of the marble panel Antero Kukko
33ConclusionsLaser 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 dataCAD-tools for analytical and visual monitoring of the building conditionlaser scanner instrumental and methodological errors!!
34Conclusions3D 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.
35Concrete Solutions rd International Conference on Concrete Repair Venice/Padova, Italy 29 June-2 July 2009.The potential of terrestrial laser scanning for detecting the deterioration of building facades
36Outline of the presentation IntroductionIntroductionResearch projectLaser scanningBuilding facades inspectionField measurementsResultsConclusionsFuture workField measurementsResultsConclusionsFuture workPage 36
37Research projectThis 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 PuttonenInstitute of Photogrammetry and Remote Sensing, TKK:Anna Erving; Nina Heiska; Pano Salo and Milka NuikkaFinnish Geodetic Institute:Antero KukkoIntroductionField measurementsResultsConclusionsFuture workPage 37
38How 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.IntroductionField measurementsResultsConclusionsFuture workPage 38
39Laser scanning data processing Raw observationscollected by the scannerIntroductionField measurementsRaw XYZformatting and exporting the raw data into raw XYZ data from the scanning systemResultsAligned XYZdetermined by processing third-party softwareConclusionsFuture workProcessed modelis the basis for the interpretation and decision makingPage 39
40Laser scanning for building facades inspection IntroductionField measurementsResultsConclusionsExamples:Deformations and bending of concrete elementsDelamination of bricks and rendering coatingsReconstruction of building facades drawings (comparing to original drawings)Future workPage 40
41FARO LS 880HE80 terrestrial laser scanning system Field measurementsIntroductionField measurementsResultsFARO LS 880HE80 terrestrial laser scanning systemLeica TCA2003 tachymeterSketch of the bow-meter and the location of the measuring points on the marble panel.ConclusionsFuture workMeasurement distance to the façade4.5 m to the center of the facadeAbout 5 m to the cornersPage 41
42Bowing of marble panels IntroductionField measurementsResultsConclusionsFuture workTerrestrial laser scanning data, colored by the magnitude of the deformation in meters from the planarity.Page 42
43Bowing of marble panels IntroductionThe 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 (mm L 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 measurementsResultsConclusionsFuture workPage 43
44Bowing of marble panels: examples IntroductionField measurementsResultsConclusionsFuture workPage 44
45Bowing of marble panels IntroductionMethodMarble panelType of bowingB (mm/m)Laser scanningMar–R4–C2 (Hal)Convex6Mar–R4–C2 (Val)9Mar–R4–C4 (Hal)Concave-6Mar–R4–C4 (Val)-9Tachymeter8-10Manual measurement (Bow-meter)57-7Field measurementsResultsConclusionsFuture workResults of measurements carried out on the marble facade using terrestrial laser scanning system tachymeter and bow-meterPage 45
46Surface delamination of bricks IntroductionField measurementsResultsConclusionsAligned XYZ GeoMagic studio softwareFuture workPage 46
47Surface delamination of bricks IntroductionExample 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 measurementsResultsConclusionsFuture workPage 47
48Reconstruction of building facades drawings IntroductionField measurementsResultsConclusionsFuture workPage 48
49ConclusionsLaser scanning is not a replacement for existing condition survey techniques, but an alternative , which provides location based information on the building defects and deteriorationTerrestrial laser scanning technique gives a reasonable method for measuring the bowing of marble and many other kinds of cladding panelsThe extracting of the deterioration features of building facades like surface delamination of bricks and joint failures can be performed from the laser scanning dataDue to large amount of three dimensional data, efficient computing and analysis tools are needed to be developed and testedIntroductionField measurementsResultsConclusionsFuture workPage 49
50Measurement technology (Real world) Future work: 4D conceptIntroductionField measurementsTime (years)ResultsConclusionsAnalysisLaser scanningAutomatic evaluation of the condition of the structureCondition survey databaseFuture workPhotogrammetryVisual inspectionMeasurement technology (Real world)Page 50