Autonomous non-intrusive condition assessment of structures. Presenterat av Kamyab Zandi, Chalmers, på Betongdagen den 13 oktober 2016 i Stockholm.

1. Concrete Structures
Autonomous Non-intrusive Condition
Assessment of Structures
Betongdagen
13 October 2016, Stockholm
Kamyab Zandi
Associate Professor
Concrete Structures Research Group

2. Concrete Structures
Skurubron 1915, 1953-57
Sufficient load carrying capacity?

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Reinforcement corrosion: An important problem
• Corrosion the main cause of
degradation in many structures
• Expected climate change will increase
the degradation rate
• Built environment in Europe
~50% of national wealth
• Maintenance and repair
~50% of the expenditure in the construction industry

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Yet disasters happen…
I-5 Skagit River Bridge collapse on May 23, 2013 in the state of Washington

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http://www.upandundergroup.com/uubridges.html http://www.upandundergroup.com/uubridges.htmlwww.dot.wisconsin.gov
www.dot.wisconsin.gov www.facelift.co.uk www.dot.nd.gov
Future inspection practice …
The safety of road users/workers and flow capacity of
the transport infrastructure should not compromised
but mutually inclusive!
Current inspection practices …

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Autonomous
Data Collection
Platform
Automated
Data Interpretation
Platform
Enhanced
Damage Identification
Platform
Advanced
Structural Simulation
Platform
Structural Inspection Distress Quantification Performance Prediction
Bridge/Building Information Modelling (BIM)
① ② ③ ④
⑤

7. Concrete StructuresUNICA
Autonomous Data Collection Platform
3D reconstruction of a building skeleton

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RABIT™ Bridge assessment tool - FHWA
UNICA
Autonomous Data Collection Platform
http://cait.rutgers.edu/rabit-asce-award

9. Concrete StructuresUNICA
Automated Data Interpretation Platform
3D models with building/bridge information models (BIM)

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Unordered
digital images
SfM + MVS
Point Cloud
3D mesh
model
Crack
detection
Adjustments for
detecting
micro-cracks
UNICA
Enhanced Damage Identification Platform
Automatic generation of 3D mesh and detect concrete surface crack/spalling

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Figure 13: Overview of the earlier developments of deterioration model by PIs including major milestones
1999-2005
• development of bond
and corrosion model
and validation
2006-2010
• Extending the corrosin
model for flow of rust
and validation
2011-2014
• Simulated cracking &
spalling and validation
σt
Stress in the inclined
compressive struts
μ
-c
Yield line F1: friction
σn
σt
-σn
c
Yield line F2: the upper limit at a pull-out failure
Steel bar
ut
σn
σt
un
Bond and
corrosion layers
Advanced Structural Simulation Platform

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Advanced Structural Simulation Platform
Zandi (2010) and Zandi, Coronelli & Lundgren (2011)

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Advanced Structural Simulation Platform

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Advanced Structural Simulation Platform

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Autonomous
Data Collection
Platform
Automated
Data Interpretation
Platform
Enhanced
Damage Identification
Platform
Advanced
Structural Simulation
Platform
Structural Inspection Distress Quantification Performance Prediction
① ② ③ ④
The challenge is …
CUSTOMIZATION / INTEGRATION / VERIFICATION

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Four-point bending specimen

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Data Collection / Point cloud
3D laser scanning Structured light scanning

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Data Interpretation
Point cloud ---> (meshed) objects
Meshed object Object

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Data Interpretation
Point cloud ---> FE mesh
Course FE Mesh Fine FE Mesh

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Structural Simulation
FE model ---> structural performance
Principal Strains
Principal stresses

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Take away messages …
Future condition assessment methods
Safer | Quicker | more accurate
• Safer: human role minimized, non-intrusive
• Quicker: autonomous, automated, integrated
• More accurate: human error minimized, massive
data

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Collaborators
Dimitrios Boubitsas (CBI)
Shayan Fahimi (CBI – MS student)
Karin Lundgren (Chalmers)
Mario Plos (Chalmers)
Mohammad Tahershamsi (Chalmers)
Mathias Johansson (SP-MT)
Jörgen Spetz (SP-MT)
Mathias Flansbjer (SP-Safety)
Mani Golparvar-Rad (University of Illinois at Urbana-Champaign)
Tim Bretl (University of Illinois at Urbana-Champaign)

23. Concrete Structures
References
Most of them available in full-text on http://publications.lib.chalmers.se/
Berg, Fredrik and Johansson, David (2011): Design of Test Set-up using FEM: Pilot tests on Anchorage of
Naturally Corroded Reinforcement. Master Thesis, Chalmers tekniska högskola.
Lundgren, K., Kettil, P., Zandi Hanjari, K., Schlune, H. and San Roman, A. S. (2012): Analytical model for
the bond-slip behaviour of corroded ribbed reinforcement, Structure and Infrastructure Engineering,
Volume 8, Issue 2, pp 157-169.
Lundgren K. and Plos, M. (2006): The effect of corrosion on bond in reinforced concrete. In Proceedings
“European Symposium on Service Life and Serviceability of Concrete Structures ESCS-2006”, Espoo,
Finland, June 2006, pp. 252-257.
Lundgren, K., Soto San Roman, A., Schlune, H., Zandi Hanjari, K., Kettil, P. (2007): Effects on bond of
reinforcement corrosion. International RILEM workshop on Integral Service Life Modeling of Concrete
Structures, 5-6 November 2007, Guimaraes, Portugal, RILEM Publications S.A.R.L, pp 231-238.
Lundgren, K. (2007): Effect of corrosion on the bond between steel and concrete: an overview. Magazine
of Concrete Research, Vol. 59, Issue 6, pp. 447-461.
Tahershamsi, M. (2013): Anchorage of Corroded Reinforcement in Existing Concrete Structures. Licentiate
Thesis, Chalmers tekniska högskola.
Zandi Hanjari, K. (2010): Structural Behaviour of Deteriorated Concrete Structures. PhD Thesis, Chalmers
tekniska högskola.
Zandi, K. (2014): Corrosion-Induced Cover Spalling and Anchorage Capacity, accepterad för publicering i
Structure and Infrastructure Engineering.
Zandi Hanjari, K., Coronelli, D. and Lundgren, K. (2011): Bond capacity of severely corroded bars with
corroded stirrups, Magazine of Concrete Research, Vol. 63, No. 12, pp. 953-968.