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Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
Instrument Supported Tree Evaluation in Hungary
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Instrument Supported Tree Evaluation in Hungary

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Divos Presentation Ndt2009 Id

Divos Presentation Ndt2009 Id

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  • 1. Instrument supported tree evaluation in Hungary<br />Ferenc Divos<br />University of West Hungary<br />Jozsef Bodig wood NDT Laboratory<br />Beijing, <br />16th International Wood NDT Symposium<br />October 12-14, 2009<br />
  • 2. Content<br />Visual tree evaluation<br />Acoustic test, single path<br />Acoustic tomography<br />Acoustic root detection<br />Pulling test<br />Seedling test<br />Conclusions<br />
  • 3. Human case Tree case<br />1st step: visual investigation<br />2nd step can be:<br /> - X-ray<br /> - Ultrasonic<br /> - CT, or MR<br /> - ………………<br />Arborist and patient <br />2nd step: NDT<br /> - acoustic tomography<br /> - pulling test<br /> - root detection<br /> - tree mechanics<br />
  • 4. 1. Visual tree evaluation<br />Goal: tree related risk reduction.<br />Requirement: well trained expert.<br />Expert focusing to...<br />
  • 5. ... holes<br />
  • 6. ... openings, truntcations<br />
  • 7. ... fungi fruits, wounds<br />
  • 8. ... crone structure, tree shape<br />
  • 9. ... soil conditions, environment<br />
  • 10. Failure type 1.<br />
  • 11. Failure type 2.<br />
  • 12. Accident in Budapest, 2008<br />
  • 13.
  • 14. 2. Acoustic defect detection<br />Single path (2 sensors)<br />
  • 15. Principle of decay detection<br />Sound propagation in an intact and in a decayed tree.<br />
  • 16. Principle of decay detection<br />
  • 17. Principle of decay detection<br />
  • 18. FAKOPP Microsecond Timer<br />Measurement perpendicular to the grain<br />
  • 19.
  • 20. Evaluation of measurement results<br />The relative velocity change (RVC) is a measure of the defect size. If RVC is lower than 90% of the velocity in an intact tree, the tree contains an internal defect.<br />
  • 21. Sound propagation<br />Oak disk, grid size is 2 by 2 cm, time resolution is 20 s.<br />
  • 22. The setup for wave mapping<br />
  • 23.
  • 24.
  • 25.
  • 26.
  • 27.
  • 28.
  • 29.
  • 30. 3. Acoustictomography<br />by using more sensors<br />
  • 31. Intact poplar trunk<br />
  • 32. Decayed poplar trunk<br />
  • 33. FAKOPP 2D Acoustic Tomograph<br />
  • 34.
  • 35.
  • 36.
  • 37.
  • 38.
  • 39.
  • 40.
  • 41.
  • 42.
  • 43.
  • 44.
  • 45.
  • 46.
  • 47.
  • 48. FAKOPP 2D<br />Acoustic Tomograph<br />
  • 49. Linden and <br /> Nut tree<br />
  • 50.
  • 51.
  • 52. 4. Acoustic Root Detection<br />
  • 53. Signal attenuation in soil is high, high sensitivity sensor is required<br />Amplitude (mV)<br />Distance (m)‏<br />
  • 54. P-vawe velocity in soil is 300 m/s<br />Distance (mm)‏<br />Propagation time (ms)‏<br />Velocity in root is 3000 m/s <br />
  • 55. Theoretical wavefront around a tree<br />
  • 56. Soil velocity depends on depth<br />
  • 57. Setup for acoustic root detection<br />
  • 58.
  • 59. High sensitivity (10V/g) <br />soil sensors<br />
  • 60.
  • 61. Velocity distribution around a tree<br />
  • 62.
  • 63.
  • 64.
  • 65.
  • 66. Root depth is measured by a steel bar.<br />
  • 67.
  • 68.
  • 69.
  • 70.
  • 71. Limitation of acoustic root detection<br />Large rocks, fence, concrete roads guidesthe sound propagation.<br />Technique is working well in parks and forest, but limited in urban area. <br />
  • 72. 5. Pulling test<br />
  • 73. Generalized <br />Inclination -<br /> tipping load curve<br />From Koch, 1989<br />
  • 74.
  • 75. Inclination sensor<br />
  • 76. Force sensor<br />
  • 77. Force display<br />
  • 78. Loading device<br />
  • 79. Pulling test in progress<br />
  • 80. Fitted curve and extrapolated maximum load<br />
  • 81. Evaluation<br />Generalizedinclination curve:<br /> = 1/3 tan(p/73,85) +0,00005 p2- 0,0009 p<br />where: : inclination in degree<br />p: force in % of maximum load.<br />
  • 82.
  • 83. Inclination (degree)<br />Force (N)<br />
  • 84. Inclination (degree)<br />Force (N)<br />
  • 85. Results of pulling test<br />
  • 86. Limitations of pulling test<br />Uncertain factors: <br /> wind speed, <br />drag factor, <br /> curve extrapolation,..<br />Load is not static, but dynamic.<br />Trees are falling down not only in storms, <br /> but sometimes in wind silent condition. <br />
  • 87. Paulownia tomentosa trees in the yard of city the hall Kecskemét, the city of Zoltan Kodály<br />
  • 88. Kecskemét, city hall<br />
  • 89.
  • 90.
  • 91.
  • 92.
  • 93. Mechanical model for tree stability evaluation<br />
  • 94.
  • 95. Green wood material compression strength can be predicted by MOE. <br />A stress wave velocity in fiber direction, together with the nominal density of the tree, provides the dynamic MOE and compression strength.<br />
  • 96. Tree stiffness determination and strength prediction<br />MOE=V2<br />Higher velocity:<br /> higher MOE<br /> higher strength<br /> longer fibers<br /> low microfibril angle<br />
  • 97. 6. Ultrasonic seedling test<br />
  • 98. Shear type sensor<br />
  • 99. Sensor attached to seedling<br />
  • 100. Sensor attached to seedling<br />
  • 101. Testing oak seedling<br />
  • 102. 7. Conclusions<br /><ul><li>Visual Tree Evaluation is the most common tree evaluation technique.
  • 103. Recently acoustic test becoming a standard tree evaluation technique in Hungary.
  • 104. Acoustic technique is a reliable tool for tree trunk evaluation.
  • 105. Acoustic root detection technique is approved in the practice.
  • 106. Instrument supported tree evaluation increases tree safety, reduces tree related risk.</li></li></ul><li>Thank you for <br />your attention!<br />

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