measuring techniques of building façades rak-43.3312 repair methods of structures ii (4 cr) esko...
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Measuring techniques of building façades
Rak-43.3312 Repair Methods of Structures II (4 cr)
Esko Sistonen
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)
The Use of ICT 3D Measuring Techniques for Visual Inspection
of Building Facades
KITARA- Rakentamisen laadun parantaminen 3D-mittaustekniikan avulla
– Background• Building envelope• Deterioration of building facades • Visual inspection• Similar laser-scanning research (different fields)
– Research focus– Methodology– Some expected results
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
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.
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?).
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)
Building envelope
Deterioration of building facades
Spalling of concrete cover due to corrosion
Frost damage
Cracking of concrete panels
Bending of concrete panels due to frost action
• 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
Literature reviewRoad surface texture inspection using high resolutionTransverse profile measurementsC. MAYS et al 2006,Phoenix Scientific Inc.
Literature reviewFeature Extraction And Modeling Of Urban Building From Vehicle-Borne Laser Scanning Data B.J. Li, 2004 Hong Kong, China
DoPP = Density of Projected points
Literature review Deformation Measurement using Terrestrial Laser Scanningat the Hydropower Station of GabčíkovoThomas SCHÄFER, 2004Slovakia
Selecting building facades
Selecting building facadesRaiviosuonmäki 7, Vantaa. Kohteessa on kaksi rakennusta 5- ja 4-kerrosta
FARO LS 880 laser scanner. www.faro.com
Scanning
The tacheometer Leica TCA2003
Potential research idea
Before earthquake After earthquake
• 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
Results Examples from the literature review
Results
Examples from the literature review (quality control in the metal industry using laser scanning)
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
Bowing Potential Test
Bow-meter
Field measurements (LTS & Tachymeter)
Anna Erving
KITARA- Rakentamisen laadun parantaminen 3D-mittaustekniikan avulla 20.3.2007
Building Quality
KITARA- Rakentamisen laadun parantaminen 3D-mittaustekniikan avulla
Building Quality
KITARA- Rakentamisen laadun parantaminen 3D-mittaustekniikan avulla
Building Quality
KITARA- Rakentamisen laadun parantaminen 3D-mittaustekniikan avulla
Building Quality
Antero Kukko
Crack in the building facade footing
KITARA- Rakentamisen laadun parantaminen 3D-mittaustekniikan avulla
Nina Heiska
The surface structure of the marble panel
Antero Kukko
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!!
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.
The potential of terrestrial laser scanning for detecting the
deterioration of building facades
Concrete Solutions 20093rd International Conference on Concrete RepairVenice/Padova, Italy29 June-2 July 2009.
Outline of the presentation
o Introduction• Research project
• Laser scanning
• Building facades inspection
o Field measurements
o Results
o Conclusions
o Future work
Page 36
Introduction Introduction
Field measurements
Field measurements
ResultsResults
ConclusionsConclusions
Future workFuture work
Research projecto This paper is a part of the research project:
“Use of ICT 3D measuring techniques for high quality construction” o 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
Page 37
Introduction Introduction
Field measurements
Field measurements
ResultsResults
ConclusionsConclusions
Future workFuture work
How laser scanning works
Page 38
Introduction Introduction
Field measurements
Field measurements
ResultsResults
ConclusionsConclusions
Future workFuture work
o Laser scanners use either the Time-of-Flight (TOF) measurement method or phase-based measurement to obtain target point distance.
o 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.
o Advanced high-speed electronics are used to measure the small time difference and compute the distance range to the target.
o The distance range is combined with high resolution angular encoder measurements to provide the three-dimensional (X,Y,Z) location of a point.
o Laser scanner is capable of measuring up to 50,000 distances per second.
Laser scanning data processing
Page 39
Introduction Introduction
Field measurements
Field measurements
ResultsResults
ConclusionsConclusions
Future workFuture work
Raw XYZformatting and exporting the raw data into
raw XYZ data from the scanning system
Raw XYZformatting and exporting the raw data into
raw XYZ data from the scanning system
Aligned XYZdetermined by processing third-party
software
Aligned XYZdetermined by processing third-party
software
Processed modelis the basis for the interpretation and
decision making
Processed modelis the basis for the interpretation and
decision making
Raw observationscollected by the scanner
Raw observationscollected by the scanner
Laser scanning for building facades inspection
Page 40
Introduction Introduction
Field measurements
Field measurements
ResultsResults
ConclusionsConclusions
Future workFuture work
Examples:• Deformations and bending of concrete elements • Delamination of bricks and rendering coatings • Reconstruction of building facades drawings
(comparing to original drawings)
Field measurements
Page 41
Introduction Introduction
Field measurements
Field measurements
ResultsResults
ConclusionsConclusions
Future workFuture work
FARO LS 880HE80 terrestrial laser
scanning system
Leica TCA2003 tachymeter
Measurement distance to the façade• 4.5 m to the center of the facade• About 5 m to the corners
Sketch of the bow-meter and the location of the measuring points on the marble panel.
Bowing of marble panels
Page 42
Introduction Introduction
Field measurements
Field measurements
ResultsResults
ConclusionsConclusions
Future workFuture work
Terrestrial laser scanning data, colored by the magnitude of the deformation in meters from the planarity.
Bowing of marble panels
Page 43
Introduction Introduction
Field measurements
Field measurements
ResultsResults
ConclusionsConclusions
Future workFuture work
• 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.
1000L
d B
Bowing of marble panels: examples
Page 44
Introduction Introduction
Field measurements
Field measurements
ResultsResults
ConclusionsConclusions
Future workFuture work
Bowing of marble panels
Page 45
Introduction Introduction
Field measurements
Field measurements
ResultsResults
ConclusionsConclusions
Future workFuture work
Method Marble panel Type of bowing B(mm/m)
Laser scanning
Mar–R4–C2 (Hal) Convex 6Mar–R4–C2 (Val) Convex 9Mar–R4–C4 (Hal) Concave -6Mar–R4–C4 (Val) Concave -9
Tachymeter
Mar–R4–C2 (Hal) Convex 8Mar–R4–C2 (Val) Convex 8Mar–R4–C4 (Hal) Concave -9Mar–R4–C4 (Val) Concave -10
Manual measurement (Bow-meter)
Mar–R4–C2 (Hal) Convex 5Mar–R4–C2 (Val) Convex 7Mar–R4–C4 (Hal) Concave -6Mar–R4–C4 (Val) Concave -7
Results of measurements carried out on the marble facade using terrestrial laser scanning system tachymeter and bow-meter
Surface delamination of bricks
Page 46
Introduction Introduction
Field measurements
Field measurements
ResultsResults
ConclusionsConclusions
Future workFuture work
Aligned XYZGeoMagic studio
software
Surface delamination of bricks
Page 47
Introduction Introduction
Field measurements
Field measurements
ResultsResults
ConclusionsConclusions
Future workFuture work
• 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.
Reconstruction of building facades drawings
Page 48
Introduction Introduction
Field measurements
Field measurements
ResultsResults
ConclusionsConclusions
Future workFuture work
Conclusionso 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
o Terrestrial laser scanning technique gives a reasonable method for measuring the bowing of marble and many other kinds of cladding panels
o 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
o Due to large amount of three dimensional data, efficient computing and analysis tools are needed to be developed and tested
Page 49
Introduction Introduction
Field measurements
Field measurements
ResultsResults
ConclusionsConclusions
Future workFuture work
Future work: 4D concept
Page 50
Introduction Introduction
Field measurements
Field measurements
ResultsResults
ConclusionsConclusions
Future workFuture work
Measurement technology (Real world)
Laser scanning
Photogrammetry
Visual inspection
Automatic evaluation of
the condition of the structure
Condition surveydatabase
Analysis
Time (years)