Proučavanje odnosa između statičnog i dinamičnog modula stijena

Non-destructive techniques based on the propagation of ultrasonic wave through the elastic medium were used for determination of dynamic modulus of selected samples of rocks in laboratory. The calculated values of dynamic modulus were compared with values of static modulus determined in laboratory on samples tested by applied loading. A method of estimation of the static modulus in situ conditions, where the measurements cannot be carried out, is discussed.Za laboratorijsko određivanje elastičnog i dinamičnog modula odabranih uzoraka stijena uporabljene su nerazarajuće tehnike temeljene na širenju ultrazvučnih valova kroz elastični medij. Izračunate vrijednosti dinamičkog modula su uspoređene s vrijednostima statičnog modula određenog u laboratoriju na uzorcima testiranim primjenom opterćivanja. Raspravljena je i metoda utvrđivanja statičnog modula u uvjetima “in situ” gdje mjerenja ne mogu biti provedena

Nuclear Magnetic Resonance Spectral Function and Moments for Proton Pairs in Powdered Paramagnetic Substances MnSO4·H2O and NiSO4·H2O

The NMR spectrum is determined by interaction of resonating nuclei between the particles of the substance. These interactions depend on the spatial arrangement of the particles and their motion. Parameters characterizing interactions between the paramagnetic ions Me2+ (Me = Mn and Ni) and the protons of crystalline water in powdered MnSO4·1H2O and NiSO4·1H2O were derived from the temperature dependences on the second moment of the NMR spectra. The parameters characterizing the local magnetic field acting on the proton pairs were calculated and compared with those obtaind from the analysis of the shape of the NMR spectrum

Proučavanje odnosa između statičnog i dinamičnog modula stijena

Non-destructive techniques based on the propagation of ultrasonic wave through the elastic medium were used for determination of dynamic modulus of selected samples of rocks in laboratory. The calculated values of dynamic modulus were compared with values of static modulus determined in laboratory on samples tested by applied loading. A method of estimation of the static modulus in situ conditions, where the measurements cannot be carried out, is discussed.Za laboratorijsko određivanje elastičnog i dinamičnog modula odabranih uzoraka stijena uporabljene su nerazarajuće tehnike temeljene na širenju ultrazvučnih valova kroz elastični medij. Izračunate vrijednosti dinamičkog modula su uspoređene s vrijednostima statičnog modula određenog u laboratoriju na uzorcima testiranim primjenom opterćivanja. Raspravljena je i metoda utvrđivanja statičnog modula u uvjetima “in situ” gdje mjerenja ne mogu biti provedena

Research of geomechanical and geophysical parameters for assessing of rock mass stability

The paper presents the results of laboratory such as in situ geomechanical and geophysical measurements. The results were the basis for mathematical modeling of slope stability in the design of foundations for new technological line for crushing stones. In situ research aimed to verify the strength of dolomite on Schmidt Hammer tests. Geophysical measurements were determined the speed of propagation of seismic waves and the degree of fracturing of the rock massif. Slope stability assessment of new technological line was made planar and spatial mathematical model and have been proposed rock slope stabilization

Soil Profiles and Seismic Loading

The contribution estimates different geotechnical profiles of site condition change and their influences on the computed seismic response spectra and time histories final values and forms applying on the seismic structures loading. The mentioned problems methodics attitude solution is based on the computed seismic motion parameters

Fraktalna geometrija i primjena impulsne dinamičke metode u procjenjivanju poremećaja u stijenama

In this paper the fractal geometry, interpreting the size effect was used for evaluation of disturbance of samples of rocks. Fractal geometry offers a possibility to describe the non-regular structure of natural objects by fractal dimension, from which it is possible e.g. to estimate the measure of rock disturbance. The micro-disturbance of rock samples was compared with the results of ultrasonic pulsing method, where the disturbance indexes IQ were calculated from the velocities of exciting ultrasonic waves spreading through the rock medium.U radu je korištena fraktalna geometrija za tumačenje efekta veličine radi procjene poremećaja u uzorcima stijena. Fraktalna geometrija nudi mogućnost da se fraktalnim, dimenzijama opiše neregularna struktura prirodnih objekata iz čega je moguće, npr. utvrditi dimenzije poremećaja u stijenama. Mikropromjene u uzorcima stijena uspoređene su s rezultatima metode ultrazvučnog titranja gdje se indeksi promjena IQ računaju iz brzine širenja pobuđenih ultrazvučnih valova kroz medij stijena

New Principles of Process Control in Geotechnics by Acoustic Methods

The contribution describes the new solution of the control of rotary drilling process as some elementary process in geotechnics. The article presents the first results of research on the utilization of acoustic methods in identification process by optimal control of rotary drilling