Temporary Flood Protection Research at U of M. Title of presentation. Faculty of Engineering. Shawn Clark, Ph.D., P.Eng.

Transcription

1 Temporary Flood Protection Research at U of M Shawn Clark, Ph.D., P.Eng. Contributors: James Blatz, Steven Harms, Raymond Offman, Kevin Sagan Title of presentation umanitoba.ca Faculty of Engineering

2 Photo by Ken Skaftfeld, P.Eng..Before

3 Photo by Ken Skaftfeld, P.Eng. And After

4 Photo by Ken Skaftfeld, P.Eng.

5 Photo by Ken Skaftfeld, P.Eng.

6 Volunteer Sanbag Dikes

7 Limited physical evidence regarding sandbag dike performance leading to many questions about risks (height limit?). Even though not a permanent structure, little doubt sandbags will be needed in future events. Need QUANTITATIVE data!

8 Dike Interface Properties PES on WPP PES on PES WPP on WPP WPP on Sand PES on Sod WPP on SOD

9 Physical Experiments

10 Large-Scale Direct Shear Box 1m

11 Normal vs Shear Stress Summary of all Interfaces Tested in Large-Scale Shear Apparatus 140 Shear Stress (kpa) PES on PES PES on WSFPP PES on Sod WSFPP on WSFPP WSFPP on Sod RMC Sand on WSFPP Sandbags on Sod Sandbags on Sandbags Normal Stress (kpa)

12 Preparation for 8 Test

13 City of Winnipeg Design Guideline 1 2 2V:1H

14 8 Dike Near Overtopping

15 Densification by Wetting 9

16 Failure of Dike Without Poly

17 Impact of Volunteer Construction

18 6 Baseline Research Dike

19 6 Volunteer Dike

20 Wave resistance tests HRTF wave flume ( 30 m long, 1.5 wide, 1.5 high) 5 ft dike, City of Wpg. template

21

22

23 4 hr wave test duration Varied the wave height H s Sandbags from City of Winnipeg Stockpile Woven slit film polypropylene bags (WSFPP) Sand d 50 = 0.66 mm mm apparent opening size 6 mil polyethylene sheet as waterproof membrane

24

25

26 Sandbad test video clips Impact Clip 1 Impact Clip 2 Wave Clip 1 Wave Clip 2 Wave Clip 3 Wave Clip 4

27 Before After H s = 0.45 m Elevation (m) Dike Location Along Wave Flume (m)

28 Before After H s = 0.55 m Elevation (m) Dike Location Along Wave Flume (m)

29

30 Deltalok GTX sanbags Non-woven geotextile mm apparent opening size 6 mil polyethylene sheet as waterproof membrane

31

32 No Time for Sandbags Retained to provide testing / deployment of alternative flood protection methods / products. Testing and verification in the field. Employed four new products: 1. HESCO Barrier System 2. Tiger Dams 3. MuscleWall 4. ABC Waterbloc

33 HESCO Barriers

34 HESCO Barriers

35 HESCO Barriers

36 Tiger Dams

37 Muscle Wall

38 Muscle Wall

39 ABC Waterbloc

40 ABC Waterbloc

41 ABC Waterbloc

42

43

44 Syn-Tex Wave Breaker Sand-filled compartments Made of a woven polypropylene geotextile fabric Cover to protect and retain fill

45 Standardized Testing Protocol (USACE) 1. Constructability evaluation 2. Hydrostatic testing 3. Wave-induced hydrodynamic load testing 4. Overtopping 5. Debris impact test

46

47 Syn-Tex Wave Breaker Installation

48 Syn-Tex Wave Breaker Installation

49 Syn-Tex Wave Breaker Installation

50 Syn-Tex Wave Breaker Installation

51 Syn-Tex Wave Breaker Installation

52 Hydrostatic Loading virtually no movement recorded

53 Seepage Summary Water Level (inches) Water Level Aug 28 Seepage Rates Aug 29 Seepage Rates Aug 23 Seepage Rates Aug 27 Seepage Rates Change in Time (days) Seepage Rate (cfs)

54 Hydrodynamic Loading

55

56 Overtopping Test

57 Overtopping Test

58 Impact Testing 12 foot long hydro poles used 12 and 17 diameters 5 mph impact velocity 20 degree impact angle

59

60

61 Conclusions 1. Sand-filled flood protection products densify after first loading. 2. Volunteer sandbags need to be closely monitored. 3. The performance of typical sandbags decreases with wave induced loading Pressure fluctuations cause fill loss, which leads to compromised front face of the dike A compromised poly layer leads to minimal flood protection 4. Non-woven geotextile bags provide improved perfomance

62 Conclusions 1. Experience is essential for Wave Breaker installation 2. Using the steel X-frame for installation is more effective than the PVC frame 4. The Wave Breakers are very stable although the product settles as it saturates 5. Seepage occurs both at the bag/wall interface and through the product Maximum seepage rate observed was 1gpm/ft 6. Wave Breaker material maintains the product s fill

63 Future Work 1. Perform testing in a stacked configuration 2. Isolate seepage rates at bag/wall interface and through product 3. Test product on a slope

64 Thank You!

65 Title Faculty of presentation of Engineering umanitoba.ca

66 Major Task Minor Task Duration of Minor Task Manpower Used Approximate Man-Hours Duration of Major Task Preparing product for installation Unload product and installation frame from delivery truck Remove product from delivery packaging 15 min 2 people min 2 people min Orient product in appropriate test configuration Cut wall 1 to appropriate length and place in appropriate location 20 min 3 people 1 Connect walls 1 and 2 25 min 4 people min Lay out walls 2 and 3 in appropriate location 5 min 2 people 0.2 Fill first cell with sand 10 min 6 people 1 Fill subsequent cells with sand Varied greatly Varied from 3-6 people 17 Fill product with sand Move PVC frame between cells (average) Move X-frame between cells (average) 3 min Varied from 2-4 people min 2-3 people h Deliberation regarding filling technique and order Varied greatly 1-3 people 4 Cover product to complete installation Fill sandbags to weigh down cover and poly Lay out poly and get small sandbags into position 1 hr 2 people hr 3-4 people h T O T A L 32.5 hours 9.25 hours

67 Importance of Construction Quality 6' Sandbag Dike, August 6, Extensometer Summary 0.83m above base of Dike 6' Sandbag Dike, August 21, Extensometer Summary 0.83m above base of Dike Water Behind Dike Water Behind Dike Displacement (mm) Water Depth (m) Displacement (mm) Water Depth (m) Time (min) Time (min) BASELINE VOLUNTEER

68

69 Sensor Locations