using hds to assess the effects of the haiti earthquake on various types of structures
DESCRIPTION
Using HDS to Assess the Effects of the Haiti Earthquake on Various Types of Structures. Shakhzod Takhirov and Khalid Mosalam nees@berkeley and PEER University of California, Berkeley. High-Definition Leica Laser Scanners. Scan Station 2 1 unit was acquired in 2008 - PowerPoint PPT PresentationTRANSCRIPT
Using HDS to Assess the Effects of the Haiti Earthquake on Various Types of Structures
Shakhzod Takhirov and Khalid Mosalam Shakhzod Takhirov and Khalid Mosalam
nees@berkeley and PEERnees@berkeley and PEER
University of California, BerkeleyUniversity of California, Berkeley
2010 Leica Geosystems Worldwide HDS User Conference, October 25-27, San Ramon, CA
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High-Definition Leica Laser Scanners
Scan Station 21 unit was acquired in 2008Single-point range accuracy of ±4mmAngular accuracies of ± 60 micro-radiansLaser beam spot size of 4mm from 0-50m rangeField of view: 360° x 270°.Built-in camera for taking snap shots of the object and specifying scan zonesCyclone software application
2010 Leica Geosystems Worldwide HDS User Conference, October 25-27, San Ramon, CA
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Background: Wood-Frame Building Evaluation after Earthquake
Wood-Frame Building Test: Before and After Scans4-5 scans in each conditionsAt least 4 reference targets for each scanBest resolution: 1000x1000 points Scans stitched together based on the reference targets
2010 Leica Geosystems Worldwide HDS User Conference, October 25-27, San Ramon, CA
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Background: Wood-Frame Building Evaluation after Earthquake
Wood-Frame Building Test: Before and After ScansContour of deformed shape of the north wall
2010 Leica Geosystems Worldwide HDS User Conference, October 25-27, San Ramon, CA
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Background: Wood-Frame Building Evaluation after Earthquake
Before and After ScansCompare vertical slices of building before and afterHDS point cloud well correlates to transducer data
2010 Leica Geosystems Worldwide HDS User Conference, October 25-27, San Ramon, CA
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Background: Wood-Frame Building Evaluation after Earthquake
Before and After ScansCompare horizontal slices of building before and afterHDS point cloud well correlates with transducer data
2010 Leica Geosystems Worldwide HDS User Conference, October 25-27, San Ramon, CA
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Background: Long Range Leica vs. Short Range Konica Minolta
Several individual scans from all sides of a specimen were obtainedStitched together in application supplied by the scanner manufacturer (Cyclone and Polygon)3D image of the specimen is generated
Model Manufacturer Range, m
Accuracy, mm
Target acquisitio
n accuracy,
mm
Achieved stitching accuracy (error)
Scan Station 2
Leica Geosystems
100 4 <1 < 4 mm
Vivid 910 Konica Minolta 1.2 0.22 NA < 0.4 mm
2010 Leica Geosystems Worldwide HDS User Conference, October 25-27, San Ramon, CA
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Background: Long Range Leica vs. Short Range Konica Minolta
Longitudinal slices:Scan Station 2 (slice thickness 4 mm: scan range ~ 10 m)Vivid 910 (slice thickness 1 mm: scan range < 1m)
2010 Leica Geosystems Worldwide HDS User Conference, October 25-27, San Ramon, CA
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Background: Long Range Leica vs. Short Range Konica Minolta
Transverse section:Scan Station 2 (slice thickness 4 mm: scan range ~ 10 m)Vivid 910 (slice thickness 1 mm: scan range < 1m)
2010 Leica Geosystems Worldwide HDS User Conference, October 25-27, San Ramon, CA
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Background: Long Range Leica vs. Short Range Konica Minolta
Points cloud from Vivid 910 scanner:Transverse sections with position transducer readingsLongitudinal sections with position transducer readings
2010 Leica Geosystems Worldwide HDS User Conference, October 25-27, San Ramon, CA
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Structural Damage Assessment in Haiti
More than 20 structures were scannedFor each scan position a panorama was generated
2010 Leica Geosystems Worldwide HDS User Conference, October 25-27, San Ramon, CA
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Structural Damage Assessment in Haiti
Environmental conditions on the sites
Structure Time of scanPeak temperature
shadow (direct sun), FDate
Residential building
PM scans NA 6/29/2010
Asscotia Hotel AM scans 104 6/30/2010
Mon Parfum PM scans 100 6/30/2010
Bank Building AM scans 106 7/1/2010
Hospital PM scans 105 7/1/2010
Block 7 AM scans 117 (136) 7/2/2010
Church PM scans 102 7/2/2010
Bridge AM scans NA 7/3/2010
2010 Leica Geosystems Worldwide HDS User Conference, October 25-27, San Ramon, CA
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Structural Damage Assessment in Haiti
Bridge damaged during the earthquake was scanned from 2 positions
2010 Leica Geosystems Worldwide HDS User Conference, October 25-27, San Ramon, CA
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Structural Damage Assessment in Haiti
3D panoramic view of the bridge from Station 2.
2010 Leica Geosystems Worldwide HDS User Conference, October 25-27, San Ramon, CA
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Structural Damage Assessment in Haiti
The cross sections of the shear key (images #1 and 2) at it face is shown in image #3. The section taken at the middle of the shear key is shown in image 4 with zoomed view shown in image 5.
9.2 mm
1 2 3 4
5
2010 Leica Geosystems Worldwide HDS User Conference, October 25-27, San Ramon, CA
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Structural Damage Assessment in Haiti
Registration of Asscotia Hotel and nearby intersection
N
2010 Leica Geosystems Worldwide HDS User Conference, October 25-27, San Ramon, CA
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Structural Damage Assessment in Haiti
Two horizontal sections at the 1st story of Asscotia Hotel are reduced in Matlab and overlaid on top of the building image in Google Earth
2010 Leica Geosystems Worldwide HDS User Conference, October 25-27, San Ramon, CA
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Structural Damage Assessment in Haiti
Clicking on balloon with Cal sign will bring interactive panoramic movie of the building and its surrounding (user can look around the shooting point and zoom into certain details)
2010 Leica Geosystems Worldwide HDS User Conference, October 25-27, San Ramon, CA
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Structural Damage Assessment in Haiti
Clicking on balloon with Cal sign will bring interactive image that contains links to points clouds generated by the laser scanner (TruView), so measurements of the objects can be performed
2010 Leica Geosystems Worldwide HDS User Conference, October 25-27, San Ramon, CA
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Structural Damage Assessment in Haiti
Points with colors based on deviation of columns from a vertical plane show residual deformation of south wall of Asscotia Hotel
2010 Leica Geosystems Worldwide HDS User Conference, October 25-27, San Ramon, CA
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Structural Damage Assessment in Haiti
Residual drift and directivity is estimated from the difference of the top and bottom slices
7.4 7.5 7.6 7.7 7.8 7.9 8 8.1 8.2-0.8
-0.6
-0.4
-0.2
0
0.2
0.4
0.6
East-West Coordinate (m)
Nor
th-S
outh
Coo
rdin
ate
(m)
Scans of Bottom and Top Portions of First-Story Columns (1 m Apart)
2.3%
Bottom Slice
Top Slice
-0.8 -0.6 -0.4 -0.2 0 0.2 0.4 0.6
1.5
2
2.5
3
3.5
East-West Coordinate (m)
Nor
th-S
outh
Coo
rdin
ate
(m)
Scans of Bottom and Top Portions of First-Story Columns (1 m Apart)
3.4%
Bottom Slice
Top Slice
2010 Leica Geosystems Worldwide HDS User Conference, October 25-27, San Ramon, CA
22
Structural Damage Assessment in Haiti
Two horizontal sections at the 1st story of Asscotia Hotel were reduced in Matlab and overlaid on top of the building image in Google Earth showing calculated residual drifts in
the columns
2010 Leica Geosystems Worldwide HDS User Conference, October 25-27, San Ramon, CA
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Structural Damage Assessment in Haiti: Validation
Corner beam-column specimen for a study on non-ductile RC frames
2010 Leica Geosystems Worldwide HDS User Conference, October 25-27, San Ramon, CA
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Structural Damage Assessment in Haiti: Validation
Validation of the technique in the lab conditions: digital level readings were 10.82% (top) and 11.82% (bottom)
2010 Leica Geosystems Worldwide HDS User Conference, October 25-27, San Ramon, CA
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Structural Damage Assessment in Haiti
Block 7 from Google Earth imagery taken on January 25, 2010
2010 Leica Geosystems Worldwide HDS User Conference, October 25-27, San Ramon, CA
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Structural Damage Assessment in Haiti
In opposite to conventional ground surveillance laser scans quantify the degree of permanent damage and its directivity
1st building at south-east corner
Ground observations presented by Eduardo Fierro
2010 Leica Geosystems Worldwide HDS User Conference, October 25-27, San Ramon, CA
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Structural Damage Assessment in Haiti
In opposite to conventional ground surveillance laser scans quantify the degree of permanent damage and its directivity
2nd building at south-east corner
-21 -20 -19 -18 -17 -16 -15 -14 -13 -12 -11-2
-1
0
1
2
3
4
5
6
7
8
0.8%
1.8%
East-West Coordinate (m)
Nor
th-S
outh
Coo
rdin
ate
(m)
Scans of Bottom and Top Portions of First-Story Columns (1 m Apart)
Bottom Slice
Top Slice
Ground observations presented by Eduardo Fierro
2010 Leica Geosystems Worldwide HDS User Conference, October 25-27, San Ramon, CA
28
Structural Damage Assessment in Haiti
Overall residual drift and directivity is estimated from the difference of the top and bottom slices for Asscotia Hotel
Rotation [radians]
X-translation
[mm]
Y-Translation
[mm]
Drift translation vector [%]
Drift angle to X
[degrees]0.0013 -14.4 -27.5 3.1 207.60
Thank you!
The authors acknowledge the financial support, Award # 1034808, from the National Science Foundation through the RAPID Program. Thanks are due to Mr. E. Fierro and Prof. E. Miranda for being members of the reconnaissance team. The following PEER/nees@berkeley summer interns: Victoria Servin, Clay Sorensen, and Sean Wade, contributed to the pre- and post-field work using the laser scanners. Their help is gratefully acknowledged.
http://nees.berkeley.edu