Open Pit Mining Operations
The previous topic has established that surface mining operations include several main activities that include the ore extraction or mine of the material, the overburden excavation and removal, the overburden transport, the waste disposal, the low grade material pile and transport for future treatments or separated process. The ore extraction and the material handling process […]
Open Pit Slope Design & Stability
In the concept of mining a deposit, mining operations should be planned and organized in order to maximize the productivity. Slope stability issues directly affect the productivity. It’s for these reasons that they need to be addressed with theoretical and technical expertise. And the realization of a surface mine, 3 fundamental processes should be taken […]
Surface Open-pit Mining
First of all let’s define what we mean with surface mining. Surface mining means the extraction of mineral deposits or coal reserves or stones of different kinds that are outcropping the earth’s surface or located at shallow depth from it. The economic depth for surface mining can range from 100 metres to 1 kilometre and […]
Types of Rock Failure
Rock mass failure does not always involves discontinuities. There are cases, especially for excavations, like the tunnel you see on this photo where the stress simply exceeds the strength of the rock metrics, and, hence, this later can fail. We have seen, in a previous topic, that creating an opening in a rock mass modifies […]
Rock Joint Failure
In previous topics, we have seen that discontinuities constitutes as a weakness in the rock mass. In fact, failure of a slope, for example, is often triggered by the failure of discontinuities in triggering block instability. These can occur on natural or man-made slopes. This figure illustrates two possible failure scenarios involving failure of discontinuities. […]
Ground Rock Stress Distribution
In previous topics, we’ve discussed strengths of materials because failure typically occurs when stresses exceed the strengths, it is important to know the stress distribution in a ground close to an opening, for example. This will be the topic of this module, but first, let’s consider vertical stress. To some extent, this represents at a […]
Rock Mass Classification – Rock Mass System
For most rock engineering projects, it is required to characterise not only the intact rock, but also the rock mass as a whole, and this in terms of strength and deformability. Indeed we said, in a previous topic, that the presence of discontinuities tend to confer to the rock mass lower strengths and higher deformability. […]
Rock Discontinuities Characterisation
We have seen in the previous topics that discontinuities are critical for the behavior of a rock mass. Hence, for most engineering projects, it’s important to detect the presence of discontinuities and characterise the discontinuities. When it comes to the field, what we actually see of the discontinuities, most of the time, we see only […]
Rock Joint Strength – Shear Test
In this topic, we will present two important aspects of discontinuities, namely the roughness and shear strength. These two properties are critical when it comes to the stability of a rock mass in which these discontinuities are present and like for the intact rock, the mechanics of a rock joint is that of a contact […]
Rock Strength Measurement
In this topic, we’ll present you some of the laboratory tests that can be performed to infer rock materials strength. It is important for you to know what type of tests can be done and what types of information we can gather from them.The simplest test to perform is the unconfined compression tests that will […]