application of geosynthetics and geosystems in hydraulic/coastal engineering

1. Developments in Design and Application of Geosynthetics and Geosystems in Hydraulic and Coastal Engineering Krystian W. Pilarczyk Former: Rijkswaterstaat, Road and Hydraulic Engineering Institute, Delft, the Netherlands HYDROpil Consultancy, Zoetermeer, the Netherlands [email_address]

2. Developments in Design and Application of Geosynthetics and Geosystems in Hydraulic and Coastal Engineering General Introduction Part I: Geosynthetics in Revetments Part II: Geosystems (geotextile systems)

3. Getting older I understand more and more how little I know (how little my knowledge is) Therefore I have to disappoint you I have more to say on What we do not know than What we do know Why What How Geosynthetics & Geosystems (see also CEM 2006, Rock Manual 2007)

5. Conventional Applications

12. Systems & Materials examples First: solve the problem( functional design) Then: systems & materials (structural design)

13. In the design process one has to distinguish between functional design (solve the problem) and structural design . Functional design concerns the impacts and performance of the coastal alternative with respect to coastal protection, improvement of recreational conditions and conservation of natural living resources. Structural design concerns the resistance of the coastal structure/materials to the actions of waves and currents Initial considerations Environmental conditions Functional pre-design alternative Selection of preferred scheme Detailed design Design Starting Points

14. Wave attack and Interactions with structures and Breaker index L=gT 2 /2 π =1.56T 2 L local =T (gh)^0.5 h= local depth in front of structure

15. Manufacturing , Products and Specifications Wovens Non-wovens

16. Geosynthetics: types and properties Terrafix non-woven composite Wovens vs. Non-wovens

17. Geotextiles

18. Specifications Example of woven materials

19. Remarks on specifications: woven vs. non-woven Wovens: high strength available, small elongation, bad performance at puncturing Non-wovens:lower strength, high elongation, good performance at puncturing, Good soil protection (if thick, i.e., needle-punched) Elongation at break

20. Example of geotextile properties

21. Bed and bank protection /mattresses/ high pulling forces - high tensile strength needed (wovens)

22. Composite products for special applications Woven for strength Non-woven for filtering or surface protection (The type of interconnection is very important for performance) Also non-woven composites

24. Part I Geosynthetics in Revetments

27. Prototype or large-scale verification uplift internal erosion Evidence of failure

28. Stability criteria revetments : wave attack For first estimation/conceptual design) Breaker index F=2.25 riprap F= 3-3.5 basalt F=4-6 blocks b = 0.5 for rip rap b = ½ to 2/3 for blocks Block revetments Usually in diagram form: www.tawinfo.nl

29. Example of stability diagram More examples can be found in: Dikes and Revetments, 1998, ed.K.W. Pilarczyk http://books.google.nl/books?ct=title&q=Coastal+Protection+,+Pilarczyk&lr=&sa=N&start=40

30. Pilarczyk’s formula for first estimation α = slope angle F= Φ Ψ u =2.25 Ψ u Ψ u = upgrading factor in respect to riprap ( Ψ u=1 and F= Φ = 2.25) www.tawinfo.nl

31. Example of composition and construction (Basalton) Geotextile filter Cushion layer Clay or sand Basalton

32. Block mats Cabled system

33. Cabled mat Blocks connected to geotextile by pins

34. Importance of proper composition/ leakage length example or Combined resistance/permeability influence of geotextile Geosynthetic is only one of the components involved

37. Principles of Filters arrest grains

38. Blockage of particles and sieve curves for geometrically closed filters

39. Geotextiles; comparison with granular filters Possible effectiveness of geotextile in filter: sieve curves and situation

40. O 90 < (1 to 2) D 90, base Definitions apertures geotextile and migration of fine particles

41. A lot of different criteria

42. Filter criteria for woven geotextiles; Mlynarek, 1994

43. Filter criteria for non-woven geotextiles ( Mlynarek, 1994)

44. Filter concepts Hydraulic gradients due to waves NL: geometrically sandtight: O 90 < D 90

45. Design diagram for geotextile filters Delft Hydraulics calculation programs

46. Testing and reality (performance) tests in FilterBox Index tests

47. Geotextile on clay Following geometrically closed rules provides very closed geotextile susceptible to clogging. Clay (due to cohesion) has 3 times or more resistance to erosive forces. Proposed: calculate the opening of geotextile (al least) just as for sand. No official rules on that point are known (except NL).

48. Geomats and Geomattresses PROFIX-sand-sausages mat Concrete-filled geomattresses

49. Sand mat (a measure for unstable soils)

50. Erosion Control Geoweb 3dim Composite mat

53. before and after the storm Lack of design criteria

54. Damage hazards Theory of block revetments can be applied to concrete geomattresses

55. Combined permeability of a system Influence of leakage length

56. Durability of geomattresses components vs system Aging effect Mechanical damage of geotextile Execution and maintenance

58. Gabions and stone mattresses Sack gabion Box gabion and gabion mattress Cylindrical gabion Sack gabions in closure works in S. Korea (Isbash) Plastic gabions (Sack) RM 5.2.2.7

59. Stability of Synthetic Gabions in Waves TUDelft: Master of Science Thesis on the Application of Synthetic Grids in Mattress Gabion Constructions and the Stability in Waves,June 2008 Mattress construction Pilarczyk’s stability relation improved friction long short short

60. Puncturing Falling stones

61. References online http:// books.google.nl/books?ct = title&q = Coastal+Protection +,+Pilarczyk&lr =& sa = N&start =0 http://www.library.tudelft.nl/ws/search/publications/theses/index.htm?to =2008&de= Hydraulic+Engineering&n =10&fr=2008&s=1&p=2 http://www.kennisbank-waterbouw.nl/ www.tawinfo.nl (select English, downloads) http:// www.wldelft.nl/rnd/publ/search.html (insert for Author: Breteler, Gent, or other name) http://www.vandermeerconsulting.nl/ http:// www.delftcluster.nl /

63. Discussion

64. Part II Geosystems Geotextile Systems

65. Innovation in Geosystems Project approach and Design process wide view

66. Geosynthetics and Geosystems in Coastal Applications

67. floaters Geosystems in coastal engineering: Principe of inclined curtain as a coastal protection measure anchores Double row of curtains

69. Artificial Seaweed (mats) as scour protection anchor

70. Protection submarine pipelines againt scouring Vertical geo-curtains (i.e. BEROSIN) Artificial Seaweed mats, eventually in combination with a block mat

71. Kliffende House Sylt Island

72. Geobags Repair Application Geobags Usually as temporary structures/measures Filled with sand or concrete

73. Geobags; execution aspects

74. Construction of groin or breakwater with geobags

75. Application of large geobags for underwater dam at Sylt

76. Filling procedure of Mexican system Mexican (large) geobags filled with lean concrete Large bags

77. Geotubes improvement of design techniques and execution stability innovation

79. Application Geotubes

80. Design aspects of geotubes

81. Design Geotubes Calculation shape and strength Similar results using Leshchynski’s GeoCops Palmerton method

82. Remarks on specifications: woven vs. non-woven Seams and safety factors: Seams 50 to 70% of strength Safety factor ~2 Execution damage ~1.3 Chemical degradation ~ 1.5 Creep ~ 1.5 Usually total safety factor in calculation of required strength: FS ~ 4 to 5 Elongation at break For geotubes, if exposed, high strength needed 50 to 80

83. Similar results using Leshchynski’s GeoCops Calculation shape and strength

84. Distribution of pressure along geotube perimeter

85. Influence of fill-grade

86. Influence of submergence

87. Filling of Geotubes Pocket beach using geotubes

88. Example of project: AmWaj Island, Bahrein at low water

89. Functional design: wave transmission Delft Hydraulics, 2000 Geotubes core+riprap

90. Thailand Execution

94. Example of localized humps Proper anchoring and pumping technique

95. Typical section of geotextile tube application Surface protection: additional sheet ??? (usually does not work properly) Durability (still a problem) Usually, surface protection needed

96. Holes repaired with HDPE covers

97. http:// coastal.tamug.edu / am / StudentPowerpointPresentations /Laura_ Mullaney _ Geotubes _ on _ Galveston _ Island %20ppt/ Geotubes _ on _ Galveston _ Island.ppt http://coastal.tamug.edu/capturedwebsites/cepraconference/glo_coastal_presentations/samplejay/sld001.htm

98. Enclosure and Dewatering dredged materials Leshchinsky’s PC-model Nieuw applications and design techniques

99. Dike heightening with geotubes

100. Geocontainers - a new invention

101. Geocontainers; filling procedure

102. Application Geocontainers

104. INNOVATION Geocontainers Research & Development Dry tests (Nicolon) Forces and Deformations procedure

105. Terrafix Soft Rock (geocontainers) Test geocontainer non-woven

106. Installation and dumping geocontainer

107. Submerged reef, Gold Coast a view

108. Dumping loss material and Geocontainer

109. Dumping trajectory of geocontainer Accuracy of placement still a problem (especially for depth larger than 10m) high accuracy needed

110. Large-scale geocontainer tests Delta Flume

111. Large-scale tests Geotubes Delta Flume

112. Stability geotubes&geocontainers - first approximation For geotubes parallel to wave attack For geotubes perpendicular to wave attack; For L/D > 4

113. On crest On slope Stability large geobags on slopes (Oumeraci, 2002)

116. Geocontainers - PhD study by Juan Recio (2007)

117. Geocontainers Juan Recio 2007 PhD-study

118. Juan Recio Formulae & comparison Use thickness D= lc/4 ; min.D = lc/5 Current attack

119. Recio 2007 - final

120. Proposed geocontainers/geotubes reefs West India

121. Numerical simulations by Recio

122. Accuracy of placing ?! Possible application of geocontainers and geotubes (core of breakwater)

123. Geosystems Applications EuroGeo4 2008 A.Bezuijen et al.

125. A.A. Balkema, Rotterdam Remaining questions and closing remarks: - durability - execution - damage - quality control www.balkema.nl

126. Durability/long-term performance ??? to be or not to be 50 years 100 years 200 years We have to answer that ! international cooperation/joined forces ( IGS !)

127. Remember In general it can be said that geosystems as well as all engineering systems and materials have (some) advantages and disadvantages which should be recognized before a choice is made. There is not one ideal system or material. Each material and system has a certain application at certain loading conditions and specific functional requirements for the specific problem and/or structural solution.

130. Verification of design (design rules) Engineers are continually required to demonstrate value for money. Verification of a design is expensive. However, taken as a percentage of the total costs, the cost is in fact often very small and can lead to considerable long-term savings in view of the uncertainties that exist in geosystem design. The client should therefore always be informed about the limitations of the design process and the need for verification in order to achieve the optimum design

131. Reliability of design rules ??!!!

132. Monitoring of projects Systematic (international) monitoring of realized projects (including failure cases) and evaluation of the prototype data may provide useful information for verification purposes and further improvement of prediction methods. It is also the role of the national and international organizations to identify this lack of information and to launch a multiclient studies for extended monitoring and testing programmes.

136. Promotion of geosynthetics is still needed: - marketing - publicity - good cases - quality assurance/control - education & training students engineers (post-academial education)

137. www.balkema.nl Contents: 1. Introduction 2. General design methodology 3. Geosynthetics: properties and functions 4. Revetments and bed protections 5. Fill-containing geosystems 6. Geocontainers 7. Geotextile forms for sand structures 8. Screens and curtains 9. Inflatable dams 10. Geosystems in dams, dikes, banks, dunes 11. Erosion control systems 12. Remaining questions 936pages; More information:

138. Thank you Geosynthetics are benefit for our Society

139. References online http://books.google.nl/books?ct=title&q=Coastal+Protection+,+Pilarczyk http://www.library.tudelft.nl/ws/search/publications/theses/index.htm?to =2008&de= Hydraulic+Engineering&n =10&fr=2008&s=1&p=2 http://www.kennisbank-waterbouw.nl/ www.tawinfo.nl (select English, downloads) http:// www.wldelft.nl/rnd/publ/search.html (insert for Author: Breteler, Gent, or other name) http://www.vandermeerconsulting.nl/ http:// www.delftcluster.nl / www.balkema.nl (author: Pilarczyk)

140. The end And Discussion

141. Discussion

142. Remarks on non-woven geotubes We can calculate stresses for slurry in a non-woven geotextile; it should not make much a difference. If the geotextile will deform significantly, we can do the calculations in parts. Apply a little pressure, calculate the stress, use the geotextile modulus to find the elongation, add the elongation to the previous circumference L, use the modified L and run now for an increase pressure. Repeat the process until reaching the desired pressure (or height of force T).

143. However, deformations are not part of the calculations. If you wish to include its effects, you can do the following: 1. Use a certain specified height (or specified strength or specified pressure). Any specified value should be smaller than the final value. 2. Run the program and get the reinforcement force. Calculate by hand the change in circumference for geotextile (dL=T/k where k is the stiffness of the geotextile). The new L is Ln=Lo+dL. 3. Input Ln as the circumference, increase the pressure (or strength of height) by another increment, and repeat the process. 4. When you get to the final increment of strength (or height of pressure) you have the final length of the circumference and final geometry. The final length Lf minus the initial value Lo (un-deformed value) tells the amount of deformation that is likely to occur under certain working conditions for any deformable membrane. From experience, the amount of deformation (even is 5%) will have little effects on the final shape or stress. You can verify it by doing the process incrementally.

145. Geosynthetics in flood protection and dike construction

146. Traditional application of geotextiles as flood protection measures Piping boils

147. Innovative flood protection measures using geosynthetics Conventional??

148. Geosynthetics in dikes, banks and embankments

149. Inflatable Barrier Ramspol, NL Inflatable dams principle

150. Demontable Inflated Weir

151. Waterwalls water-filled bags/tubes

152. Geotextiles as filters in revetment structures Designing with geotextiles

153. Transitions = weak points