With its portable, simple and affordable attributes, the Schmidt hammer (SH) is an ideal index apparatus, which underlies its increasing popularity and expanding range of applications. The SH rebound hardness value (R) is perhaps the most frequently used index in rock mechanics practice for estimating the uniaxial compressive strength (UCS) and the modulus of elasticity (E) of intact rock both ...

[1] A mechanism for explosive volcanic eruptions based on multicomponent phase equilibria modelling of four explosive volcanic systems is proposed. In each system, either isochoric or isobaric crystallization, where either crystals or crystals and exsolved fluid are chemically fractionated from melt, leads inevitably to near-solidus dynamical instability culminating in violent explosive eruptio...

Rock fragmentation by blasting influences ore recovery and the cost of downstream operations. The development electronic detonators makes it possible to improve controlling initiation timing in projects, effect mechanism delay on rock should be studied. Fragmentation granite bench specimens with different was investigated blast experiments. Conclusions are obtained studying surface strain field...

In this paper we describe a method for segmenting the image of fragmented ore into regions and estimating a size distrubution of the ore fragments. As the image grey level is inadequate for determining the rock boundary, we propose a two-step method for segmentation. First step, apply a region growing algorithm to construct a primary region division from the image grey level. Second step, use a...

Estimating the costs of blasting operations is an important parameter in open-pit mining. Blasting and rock fragmentation depend on two groups of variables. The first group consists of mass properties, which are uncontrollable, and the second one is the drill-and-blast design parameters, which can be controlled and optimized. The design parameters include burden, spacing, hole length, hole diam...

In view of the broken rock mass in surrounding large underground caverns, 3D distribution model joints is obtained through on-site investigation and digital imaging technology, image processing software. Based on analysis mutual cutting degree geometric shape block, concepts calculation methods fragmentation bite are proposed, quantitatively described. Furthermore, multi-factor method used to e...

In this research, first of all, the existing problems in fragmentation measurement are reviewed for the sake of its fast and reliable evaluation. Then, the available methods used for evaluation of blast results are mentioned. The produced errors especially in recognizing the rock fragments in computer-aided methods, and also, the importance of determination of their sizes in the image analysis ...