Impact bending tests of rocks
Abstract
In all real bodies, deformation processes proceed in time. Mechanical characterizations that do not take time into account are approximate and in many cases prove to be inadequate. Factors such as the rate and duration of loading, the energy stored by the system have a great influence on the value of the breaking stress. In LMI a lot of work has been done to establish the physical features of the process of rock fracture by shock loading and to find out the comparative efficiency of static and dynamic methods of fracture. As a result, it was found that the fracture energy, other things being equal, is a function of the impact energy, the velocity of the impact load application, and the mass of the striking body. As for the comparison of energy expenditure in static and impact tests, it is permissible only at a comparable degree of crushing, i.e., at some minimum impact work.
References
- Baron L. I. Experimental studies of the processes of rock destruction by impact. PH of the USSR Academy of Sciences, 1962.
- Bersenev V. S. Destruction of coals by impact. Journal of Mining Institute, vol. XLI, iss. I, 1959.
- Borisov A. A. Destruction of Coals and Rocks by Impact Loading. In the collection Calculation, Design and Testing of Mining Machines, vol. 2. Uglegletehizdat, 1955.
- Burstein L. S. Testing of rocks on impact. Proceedings of the Symposium Experimental Investigations of Engineering Structures, vol. 3, 1934.
- Burstein L. S. A copter for testing rock specimens. Bulletin. State Committee for Inventions and Discoveries No. 4, 1964.
- Burshtein L. S. et al. Determination of the natural frequency of an inertial pendulum with a load at large oscillations. Journal of Mining Institute, vol. XXXVIII, iss. 3, 1968.
- Burshtein L. S. Diagrams of Dynamic Stresses of Some Rocks. Report at the All-Union Meeting on Rock Mechanics and Mountain Pressure. Novosibirsk, 1968.
- Bubok V.K. Influence of Impact Energy and Drill Rotation Angle on Drilling Speed by Impact Action Machines. In Collection Mining Equipment. Rtp. Gipronickel Inst., 1959.
- Geroitiev V. I., Kalnitsky Ya. B., Bersenev V. S. Some results of investigation of coal destruction in the massif by shock load. In V. Voprosy of Fracture and Pressure of Rocks. Ugletekhizdat, 1955.
- Kuznetsov G. N. Mechanical properties of rocks. Uglegletekhizdat, 1947.
- Protodyakonov M. M., Teder R. I. Investigation of Coal Fracture Processes by Coarse Chipping Method. Rgp. Skochinsky IHD, 1960.
- Timofeev O. V. Investigation of rock fracture by coarse chipping under impact load application. Abstract of Candidate's Dissertation, LMI, 1956.
- Shamshev F. A., Bobrovskiy E. V. To the problem of rock drillability. ONTI, 1937.