RFS Future Foresters Technology Day. Modern Tree Inspection Methods

Transcription

1 RFS Future Foresters Technology Day Modern Tree Inspection Methods

2 Is this tree safe????

3 Traditional Methods VTA Visual Tree Assessment Knowledge, Experience, Reference Books Basic Tools Mallet, Probe, Binoculars The above often cannot tell you everything. Further methods of inspection required.

4 Inspection Methods SoT ERT Microdrill DIRECT Defect Defect Remaining wall thickness? - sufficient or not? Sorbus International Limited

5 IML Resi-PD microdrill : Precision Perfected The IML Resi-PD microdrill Test and Measuring Instrument for Trees and Timber Structures The most advanced microdrill system ever produced SORBUS INTERNATIONAL LIMITED

6 Case example Laetiporus sulphureus fungus (brown rot) on an acacia tree Good compartmentalization 2015IML. All rights reserved. 6

7 Cracks Drilling resistance profile of a chestnut tree with cracks Pith at tree centre crack crack In crack area feed curve drops down to 0% amplitude The pith consists of a reduced wood density 2015IML. All rights reserved. 7

8 Two Tomographic Methods Sonic Tomography (SoT) Acoustic waves mechanical / structural info. (Stiffness, Density) Shows measuring level only Electric Resistance Tomography (ERT) Electricity - Resistance Moisture chemical composition wood cell structure Column of the trunk is measured

9 Sonic Tomography (SoT) What is needed to record a Sonic Tomogram? Timers: travel times of acoustic waves Distances between MP Software: Velocity = distance / time

10 Sonic Tomography (SoT) PICUS 3 / PRHD Sensors Main unit

11 Sonic Measurement Sorbus International Limited

12 Sonic Tomography (SoT) Example of sonic paths Timers in each sensor Receiver Receiver Receiver Impact Start Signal Receiver Receiver Damaged wood (decay, cavity..) v = MOE ρ Receiver MOE = ModulusOfElasticity ρ = Density Receiver

13 Reconstruction Algorithm Velocity on intersections determines the colour (Black = fast : Grey = slower : White = slowest) Velocity 100%

14 Photo merge (Q74 software)

15 Electric Resistance Tomography ERT Apply current Voltage measurement Sorbus International Limited

16 Electric Resistance Tomography Species dependant Information given from below ground level! Preferably used in combination with Sonic Tomograms High resistivity (low conductivity) High conductivity (low resistivity) Reference ERT ground level scan: Fungus in roots

17 Multiple scans Origin of the defect Example: root related defect Slow velocity AND high conductive wood = decay

18 Tomographic Methods Gives more information about the tree than visual inspection Documentation of the situation Does not damage compartmentalization zones Time lines for estimating future Long term relation to clients

19 TreeQinetic Static Pull / Load Test Sorbus International Limited

20 What is the Pulling Test used for? Stem fracture Uprooting Tree is loaded to simulate wind. Sorbus International Limited

21 Pulling Test How to Measure Do not exceed inclination of max 0.25 when pulling! tension compression Forcemeter Strainmeter 1/1000 mm Elastometer F Inclinometer or Tiltmeter 1/100 degrees Sorbus International Limited

22 NEW METHOD! PICUS TreeMotion Sensor system TMS Measures the effect of natural wind loading on trees to assess tree stability

23 Wind the unknown force Tree in open land / protected / tunnels Sorbus International Limited

24 PICUS TMS system Identification of trees with root anchorage problems. Combination with static pull tests. Supervision of trees near construction works. Long term monitoring of a tree to assess if: - the wind response gets better ( ie. new roots grow) - gets worse (ie roots deteriorate or have been cut) - there is no measurable change

25 TMS Sensors Tilt-meters / Inclinometers and dataloggers at the base of tree (like pulling test by Wessolly/Sinn) Inbuilt GPS, compass Base sensor at the base Control sensor 2-3 m above ground Control confirms wind tilt. Is affected by tilt AND horizontal motion. Measuring for hours, days, weeks Sorbus International Limited

26 Application and Data Analysis Software shows maximal tilts Web service PC self analysis software Sway motion of the tree Base sensor (blue) Control sensor (green) Sorbus International Limited

27 Interpretation comparing max tilts High Wind-v no/little tilt Comparing several trees 0,08 0,05 0,07 0,28 0,06 0,09 Sorbus International Limited

28 Interpretation - Bending or Rotation? Bending (good) or rotation (not as good)? Relation R between Control and Base sensor R = control / base 3,5 3,1 4,0 1,5 2,9 3,4 Sorbus International Limited

29 Tree Inspection Methods Visual Tree Assessment (VTA) (Knowledge, Experience, Mallet,probe etc) SoT The Truth ERT Microdrill TMS Pull - test Sorbus International Limited

30 Trees are amazing! Thank you!