General
In assessing the stability of tree species, the survey instrument is an important aid in understanding the actual conditions inside of a tree. Several technologies are used, and among them is undoubtedly the sonic tomography system providing a flexible applicability and accuracy. The sonic tomography "Picus ®" works on the principle that the speed of sound through the wood, depends on the modulus and the density of the same. The main damage to the trees are represented by fractures, cavities, degenerative wood (decay), which reduce the elasticity and density of the wood. These characteristics depend on the species and whether measured in absolute need of comparison with the values \u200b\u200bobtained from table standard.Il Picus ® Sonic tomograph then measure the relative speed of sound, so the system automatically calibrates each measurement.
In assessing the stability of tree species, the survey instrument is an important aid in understanding the actual conditions inside of a tree. Several technologies are used, and among them is undoubtedly the sonic tomography system providing a flexible applicability and accuracy. The sonic tomography "Picus ®" works on the principle that the speed of sound through the wood, depends on the modulus and the density of the same. The main damage to the trees are represented by fractures, cavities, degenerative wood (decay), which reduce the elasticity and density of the wood. These characteristics depend on the species and whether measured in absolute need of comparison with the values \u200b\u200bobtained from table standard.Il Picus ® Sonic tomograph then measure the relative speed of sound, so the system automatically calibrates each measurement.
Operation
The instrument consists of a set of sensors (8 to 12), which are placed at strategic points around the area you want to investigate. Each sensor is connected to a nail (0.8 - 1 mm), which allows contact with the wood. The sonic wave is generated manually by a hammer through a cable connected to "Y" to the module and the nail.
Different sensors measure the transmission time sonic wave, the times of transmission and the distance between the sensors, calculates the apparent speed sonic wave.
From these data, the software that processes the tomogram highlights the different areas of the section can be measured successively.
The data transmission to the handheld's wireless (wireless) Bluetooth.
The instrument consists of a set of sensors (8 to 12), which are placed at strategic points around the area you want to investigate. Each sensor is connected to a nail (0.8 - 1 mm), which allows contact with the wood. The sonic wave is generated manually by a hammer through a cable connected to "Y" to the module and the nail.
Different sensors measure the transmission time sonic wave, the times of transmission and the distance between the sensors, calculates the apparent speed sonic wave.
From these data, the software that processes the tomogram highlights the different areas of the section can be measured successively.
The data transmission to the handheld's wireless (wireless) Bluetooth.
Determination of the geometry of the tree
The accuracy of the survey depends on the number of sensors used and the degree of approximation of the reciprocal distance between the sensors. In the case of circular sections measuring the distance between the modules is automatically defined by measuring the circumference (ie 10 modules on a circumference of 200 cm ® 1 module every 20 cm) in the case of elliptical sections are defined axis xel'asse y. In the case of irregular sections we measure the distance of each module by creating a free form which is relevant to the real section examined, the latter procedure assures a very high degree of accuracy by reducing most of the approximations.
The accuracy of the survey depends on the number of sensors used and the degree of approximation of the reciprocal distance between the sensors. In the case of circular sections measuring the distance between the modules is automatically defined by measuring the circumference (ie 10 modules on a circumference of 200 cm ® 1 module every 20 cm) in the case of elliptical sections are defined axis xel'asse y. In the case of irregular sections we measure the distance of each module by creating a free form which is relevant to the real section examined, the latter procedure assures a very high degree of accuracy by reducing most of the approximations.
measurement and definition of the tomogram
The result of the generation of "n" sonic waves is a dense network of information with all the relative velocities in the section indagata.L 'instrumental test can be performed even on different floors or sections, allowing the three-dimensional assessment of the development of caries. This is the only system to see graphically the vertical development of fungal diseases borne by the woody tissues.
Reading Tomogram
tomogram are shown in areas of different colors: black and brown areas indicate a good transmission of the waves so that the wood has been good, and normal mechanical function, the blue areas , purple or white areas are subject to severe cavities or degeneration. These areas have lost their mechanical function therefore should be paid considerable attention to evaluating their size and their positioning. You can not define with certainty the difference between a cavity and a strong degeneration (decay in advanced state) because the tissue density is very similar. In these cases it is possible to trace this difference with a careful observation of the data, from a historical reconstruction of events, from the results of visual and study to what we have. The green areas indicate an intermediate situation between the two described, it is discolored wood, wood still has a mechanical function, but prone to fungal infection. E 'can also represent graphically the limit of T / R useful to verify the amount of sound wood remaining.
Conclusions
A proper investigation of stability of a tree requires first a careful visual analysis of the deepening instrumental, with the identification of all structural defects, disease, etc.. You can not ignore this important phase for the same tomographic investigation. A valid interpretation of the tree, aimed at quantifying the risk of subsidence and the development of all cultural practices aimed at putting down of individuals, then, is the result of two distinct but complementary phases.
E 'can also share the survey at the crown or large branches.
With this technique it is possible to define very precisely the state of health of the wood of the tree, and accurately assess risk or potentially dangerous situations in order to prevent damage events.
A proper investigation of stability of a tree requires first a careful visual analysis of the deepening instrumental, with the identification of all structural defects, disease, etc.. You can not ignore this important phase for the same tomographic investigation. A valid interpretation of the tree, aimed at quantifying the risk of subsidence and the development of all cultural practices aimed at putting down of individuals, then, is the result of two distinct but complementary phases.
E 'can also share the survey at the crown or large branches.
With this technique it is possible to define very precisely the state of health of the wood of the tree, and accurately assess risk or potentially dangerous situations in order to prevent damage events.
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