Transactions on Transport Sciences, 2009 (vol. 2), issue 4
Influence of Periodic Freezing on the Value of the Elastic Modulus of Light-weight Fibre Concrete
O. Pospíchal, B. Kucharczyková, P. Misák, Z. Hlaváč, T. Vymazal
Transactions on Transport Sciences 2009, 2(4):142-149 | DOI: 10.5507/tots.2009.021
This paper deals with the influence of periodic freezing on light-weight concrete characteristics. Three different sets of light-weight concrete specimens were periodically freezing and non-destructively tested over time. Another three comparative sets of light-weight concrete specimens were tested at the same time and these sets were placed in water. The main aim was to determine and compare the dynamic elastic modulus values during and after 200 freeze-thaw cycles. The methods for this non-destructive testing were the ultrasonic impulse method and the resonance method.
Location of Steel Reinforcement and Other Reinforcing Elements using 3D GPR
T. Kordina, Z. Kadlecová$*, J. ©tainbruch
Transactions on Transport Sciences 2009, 2(4):150-157 | DOI: 10.5507/tots.2009.022
This paper evaluates the results of the first experimental 3D GPR measurements by the DIBEKON scanner on a physical model. The objective of the series of measurements carried out was to determine the applicability of various types of antennae (800 MHz and 1600 MHz) in the detection of steel reinforcement and the influence of the measurement density on the quality of the resulting image of the environment examined.
The Possibilities of Nonlinear Ultrasonic Spectroscopy for the NDT in Civil Engineering
Transactions on Transport Sciences 2009, 2(4):158-165 | DOI: 10.5507/tots.2009.023
Current methods of non-destructive ultrasonic material testing are based on the analysis of elastic wave reflection, absorption and interference. These methods are difficult to apply to inhomogeneous building materials showing tiny cracks and defects distributed throughout the specimen bulk, or in the cases where the defect size is comparable with the wavelength. Analysis of these phenomena occurring in intricate shapes is also difficult. To cope with such problems, application of wave propagation related nonlinear effects and higher harmonic signal generation in the defect vicinity is advisable. Due to the presence of defects, the atomic potential...
NDT of Mechanical Damaged Concrete Specimens by Nonlinear Acoustic Spectroscopy Method
M. Matysik, I. Plskova, M. Korenska, B. Kucharczykova
Transactions on Transport Sciences 2009, 2(4):166-171 | DOI: 10.5507/tots.2009.024
Current research and development of non-linear ultrasonic spectroscopy methods shows these methods to be very promising for material testing and defectoscopy in the near future. Our experiments focused on the testing of lightweight concrete specimens using the single-frequency excitation method. We studied the concrete specimens' structure after having been stressed by a mechanical force. Measurements were realized before and after mechanical loading.
Use of Palmtop Computers for Monitoring Traffic
M. Bíl, M. Bílová, J. Martínek
Transactions on Transport Sciences 2009, 2(4):172-179 | DOI: 10.5507/tots.2009.025
On the basis of a cycling traffic count carried out in the town of Olomouc a new method of monitoring traffic was presented based on the use of palmtop computers (PDAs). For short-term traffic counts, this method may entirely replace the commonly used paper forms. In addition, this method provides more possibilities, namely the recording of the exact time of vehicle passing and a description of the direction of vehicle movement. Almost all the software used for the preparation and processing of data is freely available, which allows all interested people to use this method.
Ground Penetrating Radar as a Tool for the Diagnostics of Concrete Pavements
J. Stryk, R. Matula
Transactions on Transport Sciences 2009, 2(4):180-187 | DOI: 10.5507/tots.2009.026
This paper describes the basic possibilities for the usage of ground penetrating radar (GPR) in road diagnostics. The opportunity for multi-channel GPR use and the limitations arising from measurements performed at high speeds are described. Particular attention is paid to the problems of the diagnostics of concrete pavements. The radar configuration used for location of dowel bars and tie bars is presented.
Durability of Concrete as a Function of the Properties of the Concrete Layer
J. Adámek, V. Juránková
Transactions on Transport Sciences 2009, 2(4):188-195 | DOI: 10.5507/tots.2009.027
The changes that the properties of construction materials undergo during this period are extremely difficult to keep track of, and the same holds for the assessment of the causes their degradation. One of the current diagnostic methods to evaluate the actual state of the concrete surface layers is the structure air permeability method. The method was developed theoretically by J.R.Torrent, who also assisted in the manufacturing of an excellent device, the TPT (torrent Permeability Tester). It is a relatively new, nondestructive method, applicable both in the laboratory and on construction sites. This paper will describe the test results from application...
Experimental Testing of the Applicability of Betatrons in Construction Radiography
O. Anton, V. Heřmánková
Transactions on Transport Sciences 2009, 2(4):196-205 | DOI: 10.5507/tots.2009.028
This paper focuses on testing the possibility of using portable betatrons in the radiography of reinforced concrete structures of greater thicknesses. The experiments were carried out in cooperation with the Research Institute of Introscopy in Tomsk (Russia).
Technical Notes on GAST Final Days
Transactions on Transport Sciences 2009, 2(4):206-207 | DOI: 10.5507/tots.2009.029