Corporate Overview. We will start shortly

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1 Corporate Overview We will start shortly

2 Case studies presentation: I-35W Bridge in Minneapolis and Punggol EC26 Building in Singapore Presented by: - Luca Manetti, S&S Manager, SMARTEC SA - Branco Glisic, R&D Manager, SMARTEC SA

3 Web Seminar You should hear my voice through your PC speaker / headset You can ask questions using the Questions panel on the right of your screen. We will answer: In the Questions Panel At the end of the presentation By Later this week you will receive link to: Presentation in PowerPoint, PDF and with narration

4 Contents Case study #1: I-35W bridge in Minneapolis Case study #2: Punggol EC26 Building in Singapore Questions and Answers

5 Case study #1: I-35W Bridge in Minneapolis Presented by: - Luca Manetti, S&S Manager, SMARTEC SA

6 Project description On Aug. 1, 2007 the I-35W bridge over the Mississippi River in Minneapolis collapsed, killing several people New Bridge built at the same location Two twin pre-stressed, reinforced concrete bridges Designed and built in record time Including SHM system

7 I-35W bridge in Minneapolis Old bridge opened to traffic in 1967 Scheduled for reconstruction in Deficiencies were acknowledged in inspection reports dating back to Mn/DOT had taken several steps to address these deficiencies. Some cracking in the approach spans was repaired or was being monitored 13 people were killed and 145 were injured Mn/DOT s initial study concluded that road-user costs due to the unavailability of the river crossing would total $400,000 per day. In addition to the road user cost study, further analysis by DEED and Mn/DOT estimate the economic impact - or loss to Minnesota s economy - at about $17 million in 2007 and $43 million in Mn/DOT = Minnesota Department of Transportation DEED = Department of Employment and Economic Development

8 Collapsed Bridge Pictures

9 Collapse causes (National Transportation Safety Board photo) This image shows a fracture in a gusset plate that played a key role in the collapse of the Interstate 35W bridge.

10 New bridge design year life span 10 lanes of traffic (5 in each direction) 1223 feet (~372m) long 189 feet (50.6 m) wide 1223 (~372m) Span 1 Span 2 Span 3 Span (100.5m) 504 (153.6m) 242 (73.6m) 147 (44.8m) Light Rail Transport-ready which may help accommodate future transportation needs 5 lanes 5 lanes (3.35m) (27.5m)

11 New bridge design 2

12 The new bridge Design-build project complete in 339 days.

13 I35 Bridge Instrumentation Cooperation between: Designer: FIGG Contractor: Flatiron / Mason Owner: MNDOT / FHWA Research: University of Minnesota Instrumentation: Roctest / SMARTEC / Others SHM system included in: Bridge bidding proposal Bridge design Bridge executive plans Fast construction planning

14 SMART Bridge System Integrated Bridge Sensor Monitoring System covering five areas: Support construction processes Record of structural behavior (structure monitoring) Control of the automated anti-icing system Intelligent Transportation System (ITS) Bridge security

15 Instrumentation I Strain Gauges Thermistors Linear Potentiometers Local static strain Local curvature Concrete shrinkage and creep Temperature Temperature gradient Thermal strain Joint movements Accelerometers (mid-spans) Traffic induced vibrations Modal Frequencies (eigen-frequencies) Corrosion Sensors Concrete resistivity Corrosion current

16 Instrumentation II Long-gauge fiber optic sensors Average strains Strain distribution along the main span Average Curvature Deformed Shape Detection of Cracks Dynamic Strains Dynamic Deformed Shape Vertical mode shapes Dynamic damping

17 SHM System Plans I

18 SHM System Plans II

19 Sensor Locations

20 Sensor Locations

21 Sensor Locations

22 Sensor Locations

23 SOFO Sensor Network span 2 SOFO Sensors LA=4m Junction box SOFO Bee (TCP-IP) Multifiber Extension cable

24 SOFO sensors installation I Bottom sensors

25 SOFO sensors installation II Top sensors Junction boxes

26 Control Room Control room

27 User Interface (simulation)

28 First results Day Night 4pm 8am

29 Load tests

30 Load test II 6aT 6iT 6aB 6iB

31 Acknowledgements Minnesota DOT Flatiron Corporation Manson Corporation University of Minneapolis

32 Corporate Overview Questions & Answers

33 Case study #2: Punggol EC26 Building in Singapore Presented by: - Branco Glisic, R&D Manager, SMARTEC SA

34 Outline Introduction Monitoring criteria Long-term measurements hours Post-tremor evaluation 2005 Conclusions

35 Punggol project - introduction Collaborative study between HDB Singapore s Public Housing Authority & Smartec, Switzerland Purpose of study As a part of quality assurance, preventive maintenance Understanding of structural behavior Long-term lifespan structural monitoring SOFO monitoring system used ~200 buildings equipped with sensors Status: 7+ years long-term monitoring including: monitoring during construction 48-hours continuous monitoring post-tremor evaluation

36 Monitoring criteria Critical structural members to be monitored Local (column) and global (building) monitoring Long-term lifespan monitoring incl. construction Structural (not material) monitoring required Costs for monitoring to be affordable, so only 10 columns monitored

37 Construction stage Six blocks founded on piles 19 storeys tall, 6 units per storey Columns are cast in-situ

38 Sensors positions C3 C2 UNIT F C9 UNIT E UNIT A C1 C10 MULTI - STOREY VOID C4 UNIT D UNIT B C5 C6 C7 C8 UNIT C 1 ST STOREY FLOOR PLAN

39 Photos of installation Embedding on-site Embedding in plant Passive zone Junction box SOFO sensor After pouring Measurement

40 Completed building

41 Average strain evolution May September /05/01 22/09/01 22/01/02 24/05/02 22/09/02 22/01/03 24/05/03 22/09/03 22/01/04 23/05/04 21/09/04 21/01/05 23/05/05 21/09/05 21/01/06 23/05/06 21/09/06 21/01/07 23/05/07 21/09/07 21/01/08 22/05/08 20/09/08 Results seven + -years record End of construction of 19 storeys 48-h 04 Tremor C1 (1675) C2 (1668) C3 (1676) C4 (1669) C5 (1663) C6 (1683) C7 (1670) C8 (1682) C9 (1662) C10 (1677) 48-h h h 07 Date Average strain [ με]

42 Assessment at local level Sensors measure axial deformation in columns Determine measured strain in columns Evaluate whether strains is acceptable by Comparison between measured strain and estimated theoretical (design) values Comparison between measured strain and ultimate strain Use 48-hours campaigns in order to: Learn the building behavior caused by daily temperature changes and inhabitant fluctuations Record the health state of the building as a reference for comparison with the future monitoring results

43 Estimation of total strain in columns Average strain measured by sensor (simplified): ε m (t) = ε s (t) +ε ϕ (t) +ε T (t) + ε sh (t) ε T = thermal strain ε sh = total shrinkage Neglected (temperature not measured) Estimated, CEB-FIP Model Code 1990 ε ϕ = creep Estimated (using ε s ), CEB-FIP Model Code 1990 ε s = elastic strain (due to load) Designed values

44 Measured vs. designed Strain components, column C Strain components, column C9 Average strain [ με] M easured (total) Shrinkage (CEB-FIP) Creep (CEB-FIP) Load (design) Total (design) Average strain [με] M easured (total) Shrinkage (CEB-FIP) Creep (CEB-FIP) Load (design) Total (design) End of constr. of 19 storeys Time -700 End of constr. of 19 storeys Time

45 Measured vs. designed - example σ ε Parabolic, SLS σ ε Linear, SLS σ ε Parabolic, ULS σ ε Measured by SOFO σ ε Linear, ULS

46 48-hrs 2004: strain & amb. temp. 48 hours, total av. strain, C6 (1683) Average strain [ με] C6 (1683) Amb. temp Amb. temperature [ C] : : : : : : :00 Time [date & hour]

47 48-hours example hours, total av. strain, C4 (1669) C4 (1669) 2004 C4 (1669) 2005 C4 (1669) 2006 C4 (1669) :00 12:00 14:00 16:00 18:00 20:00 22:00 00:00 02:00 04:00 06:00 08:00 10:00 12:00 14:00 16:00 18:00 20:00 22:00 00:00 02:00 04:00 06:00 08:00 10:00 12:00 14:00 Time [hour] Average strain [ με]

48 48-hours example (continued) hours, total av. strain, C6 (1683) C6 (1683) 2004 C6 (1683) 2005 C6 (1683) 2006 C6 (1683) :00 12:00 14:00 16:00 18:00 20:00 22:00 00:00 02:00 04:00 06:00 08:00 10:00 12:00 14:00 16:00 18:00 20:00 22:00 00:00 02:00 04:00 06:00 08:00 10:00 12:00 14:00 Time [date & hour] Average strain [ με]

49 48-hrs : RH & amb. temp. 48 hours averaged relative humidity '04, '05, '06 and '07 48 hours averaged ambient temperature '04,'05, '06 and '07 85% 31 Relative Humidity [%] 80% 75% 70% 65% 60% Averaged 2004 Averaged 2005 Averaged 2006 Averaged 2007 Averaged Amb. Temperature [ C] Averaged 2004 Averaged 2005 Averaged 2006 Averaged 2007

50 24-hrs hours averaged strain 2004, 2005, 2006 and 2007 C1 C2 C3 C4 C5 C6 C7 C8 C9 C10 Averaged strain [ με] Averaged 2004 Averaged 2005 Averaged 2006 Averaged 2007

51 Post-tremor Analysis Punggol EC26, post-tremor evaluation -450 C1 (1675) Average strain [ με] hours 2004 Before and after tremor 48-hours 2005 C2 (1668) C3 (1676) C4 (1669) C5 (1663) C6 (1683) C7 (1670) C8 (1682) -750 C9 (1662) C10 (1677) Time [date & hour]

52 Assessment at Global Level Comparison of strain development of columns per units A, B, C and E Comparison of differential deformation of columns Linear correlation between the sensors

53 During Construction Average strain [ ] nd Construction of storeys 4 th 6 th 8 th 10 th 12 th 14 th 16 th 18 th 5 th 7 th 9 th 11 th 13 th 15 th 17 th 19 th Other construction works Development of strain for C9 unusual, column over dimensioned 19/05/01 16/09/01 14/01/02 14/05/02 11/09/02 09/01/03 09/05/03 Age [Date+Time] Col. 1 Col. 2 Col. 3 Col. 4 Col. 5 Col. 6 Col. 7 Col. 8 Col. 9 Col. 10

54 Linear Correlation in long-term 0 Unit B - correlation with C4 Measurements of columns C5 C1 and C6 C3 [με] C5 (1663) C6 (1683) Measurement of column C4 C2 [με]

55 Linear Correlation in long-term 0 Unit A - correlation with C2 Measurements of columns C1 and C3 [με] C3 (1676) C1 (1675) Event Measurement of column C2 [με ]

56 Settlement in unit A 0 Unit A, average strain evolution May June 2007 Average strain [ με] C3 smaller than expected C1 bigger than expected C1 (1675) C2 (1668) C3 (1676) Settlement of column C3 evaluated to approximately 0.25 mm 1 mm 24/05/01 22/11/01 24/05/02 23/11/02 24/05/03 23/11/03 24/05/04 23/11/04 24/05/05 23/11/05 25/05/06 24/11/06 25/05/07 Date v 1 v 2 v 3 v h A 1 A 2 A 3 h A 1 A 2 A 3 L 1 L 2 Δ L 1 L 2 Δ

57 Punggol EC26 Blks 160 A & B The same contractor, the same design, the same concrete quality Average strain [ ] Punggol EC26 Blk160B - June 01 - March /06/2001 0:00 11/02/2002 0:00 28/09/2002 0:00 Average strain [ ] 15/05/2003 0:00 Time Punggol EC26 Blk160A - June 01 - March /06/2001 0:00 30/12/2003 0:00 27/01/2002 0:00 C1726 C1713 C1684 C1696 C /08/2004 0:00 16/09/2002 0:00 01/04/2005 0:00 C1719 C1717 C1723 C1697 C /05/2003 0:00 Time C1706 C1704 C1701 C1689 C /12/2003 0:00 C1707 C1705 C1710 C1698 C /08/2004 0:00 01/04/2005 0:00 Very similar results!

58 Punggol EC26 Blks 166 A & B The same contractor, the same design, the same concrete quality 0 Average strain [ ] Punggol EC26 Blk166B - June 01 - March Punggol EC26, May 2001-April 2005 C1 (1675) C2 (1668) C3 (1676) C4 (1669) C5 (1663) C6 (1683) C7 (1670) C8 (1682) C9 (1662) C10 (1677) Average strain [ ] /06/2001 0:00 27/01/2002 0:00 16/09/2002 0:00 06/05/2003 0: S1671 S1681 S1680 S S1679 S /05/200 22/11/200 24/05/ :00 S :00 S :00 S1667 S /12/2003 0:00 12/08/2004 0:00 01/04/2005 0:00 22/11/ :00 24/05/ :00 22/11/ :00 Time [date & hour] 23/05/ :00 21/11/ :00 23/05/ :00 Very similar results! Time

59 Conclusions Detected over dimensioning of column C9 will help designer to improve modeling Differential settlements detected small magnitude, doesn't influence the performance of building; settlement is however not stabilized yet and monitoring should continue The 48-hours sessions confirmed sound performance of the building in long-term and made possible post-tremor analysis The creep and shrinkage stabilizes slowly (developed 85% approximately) and dominant influence start to be ambient temperature

60 Conclusions (continued) Pioneer monitoring project for Singapore high-rise buildings: 7- years long-term monitoring successfully performed and important stages in structure life registered Enlarged knowledge concerning the real column behavior during construction (rheological effects) In spite of limitations (temperature not monitored, no continuous readings) results leads to important insights on actual behavior Monitoring strategy developed and successfully applied, monitoring system (SOFO) was properly selected and fully responded to design criteria

61 Conclusions (continued) The use of fiber-optics sensors on such a large scale sets directions that will help designers better understand the behavior of tall buildings during its life cycle from construction to service conditions Project presented in details and used as example in book Fiber Optic Methods for Structural Health Monitoring, available at SMARTEC

62 Acknowledgements Sofotec Singapore Pte Ltd Housing and Development Board, Singapore

63 Corporate Overview Questions & Answers