Road and railway tunnels in cold regions are often affected by problems related to water leakage and freezing temperatures. Water leakage in a tunnel leads to ice growth when the temperature goes below freezing and creates favourable environment for fallouts of shotcrete and rock. This paper presents results and observations from laboratory freezing – thawing experiments on rock blocks covered ...

An investigation is made into the effects of water jet pressure, nozzle diameter, traverse speed of the nozzle over the rock surface and the number of times the jet passes over the same area on the penetration of a water jet into Indiana limestone. The effectiveness of the cut is judged on the depth of cut established and the specific energy of rock removal. Pressure is varied in the range from...

1 INSTRODUCTION In the concept of geological radioactive waste disposal, argillite is being considered as a possible host rock in various countries such as France and Switzerland. This material is chosen thanks to its extremely low permeability that is required to limit the transfer of radioactive elements from the waste package towards the environment. During the construction and exploitation ...

This study was conducted to evaluate the effect of ultrasound application on the surface microhardness (VHN) and diametral tensile strength (DTS) of three high viscous glass-ionomer restorative materials (HVGIRMs). For each test (VHN and DTS), a total of 180 specimens were prepared from three HVGIRMs (Ketac-Molar Aplicap, Fuji IX GP Fast, and ChemFil Rock). Specimens of each material (n = 60) w...

Finite element method and dimensional analysis have been applied in the present paper to study a hydraulic impact, which is used in a non-explosive rock breaking technology in mining industry. The impact process of a high speed piston on liquidwater, previously introduced in a borehole drilled in rock, is numerically simulated. The research is focused on the influence of all the parameters invo...

Finite element method and dimensional analysis have been applied in the present paper to study a hydraulic impact, which is used in a non-explosive rock breaking technology in mining industry. The impact process of a high speed piston on liquid water, previously introduced in a borehole drilled in rock, is numerically simulated. The research is focused on the influence of all the parameters inv...

rock chutes are natural river training structures and are efficient energy dissipaters too. from the hydraulic and environmental point of view, rock chutes have become important structures in the natural river morphology. a physical study was conducted and flow properties were measured over rough bed materials of a rock chute, which was assembled at the pitlab center of the university of pisa, ...