Experimental Investigation of the Influence of Confining Stress on Hard Rock Fragmentation Using a Conical Pick

Background: Blasting is commonly used for loosening hard rock during excavation for generating the desired rock fragmentation required for optimizing the productivity of downstream operations. The environmental impacts resulting from such blasting operations include the generation of flyrock, ground vibrations, air over pressure (AOp) and rock fragmentation. Objective: The purpose of this research is to evaluate the suitability of different computational techniques for the prediction of these environmental effects and to determine the key factors which contribute to each of these effects. This paper also identifies future research needs for the prediction of the environmental effects of blasting operations in hard rock. Methods: The various computational techniques utilized by the researchers in predicting blasting environmental issues such as artificial neural network (ANN), fuzzy interface system (FIS), imperialist competitive algorithm (ICA), and particle swarm optimization (PSO), were reviewed. Results: The results indicated that ANN, FIS and ANN-ICA were the best models for prediction of flyrock distance. FIS model was the best technique for the prediction of AOp and ground vibration. On the other hand, ANN was found to be the best for the assessment of fragmentation. Conclusion and Recommendation: It can be concluded that FIS, ANN-PSO, ANN-ICA models perform better than ANN models for the prediction of environmental issues of blasting using the same database. This paper further discusses how some of these techniques can be implemented by mining engineers and blasting team members at operating mines for predicting blast performance.

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Use of indentation tests to study the influence of confining stress on rock fragmentation by a TBM cutter

International Journal of Rock Mechanics and Mining Sciences ◽

10.1016/j.ijrmms.2014.07.022 ◽

2014 ◽

Vol 72 ◽

pp. 261-276 ◽

Cited By ~ 60

Author(s):

L.J. Yin ◽

Q.M. Gong ◽

H.S. Ma ◽

J. Zhao ◽

X.B. Zhao

Keyword(s):

Rock Fragmentation ◽

Confining Stress ◽

Indentation Tests ◽

Tbm Cutter

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Hard Rock Fragmentation in Percussion Drilling Considering Confining Pressure: Insights from an Experimental Study

International Journal of Rock Mechanics and Mining Sciences ◽

10.1016/j.ijrmms.2021.104961 ◽

2021 ◽

Vol 148 ◽

pp. 104961

Author(s):

Yanliang Li ◽

Jianming Peng ◽

Pengyu Zhang ◽

Chaoyang Huang

Keyword(s):

Experimental Study ◽

Hard Rock ◽

Confining Pressure ◽

Rock Fragmentation ◽

Percussion Drilling

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Numerical Simulation on Cutting and Fracturing of Rock Plate with One Side Fixed and Three Sides Free

Advances in Materials Science and Engineering ◽

10.1155/2020/2136297 ◽

2020 ◽

Vol 2020 ◽

pp. 1-14

Author(s):

Zhenguo Lu ◽

Qingliang Zeng ◽

Zhaosheng Meng ◽

Zhiwen Wang ◽

Guanshun Gao

Keyword(s):

Numerical Simulation ◽

Cutting Force ◽

Cutting Tool ◽

Hard Rock ◽

Rock Fracture ◽

Rock Fragment ◽

Conical Pick ◽

Cutting Angle ◽

Saw Blade ◽

Element Erosion

Conical pick is a rock cutting tool that is commonly used in roadway driving. Pick wear frequently happens in the course of breaking hard rock. The current paper shows a new method to solve the problem of pick wear. The rock is preslit with the saw blade and then broken by the conical pick. In order to study the cutting force and features of rock fragment, the numerical model is built between rock plate and conical pick. And element erosion is added in the code to obtain the fracture result. The rock plate cutting testbed is made to testify the correctness of numerical simulation. The width, height, and thickness of the rock plate, as well as cutting angle and cutting position, which influence cutting force and rock fracture are studied. According to the results, there exist exponential relationships between cutting force and width and thickness of rock plate. In addition, a linear relationship is found between the cutting force and the height of rock plate. Furthermore, both the cutting angle and cutting depth have an influence on cutting force. In particular, the factors of thickness and height or rock plate have the most obvious influence on cutting force. It is proven that what is beneficial to rock fracture is higher height and lower thickness of rock plate.

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