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This is the complete lecture note for MNE302 Drilling, Explosives and Excavation Engineering. You can read it online below, open it in the full viewer, or download the PDF for offline study. It pairs with the course's video lectures, so you can read and watch together.
LA-NET | ONLINE LEARNING VIDEO PLATFORM FOR POST-SECONDARY & HIGHER INSTITUTION STUDENTS • Course code: MNE 302 • Course title: Drilling, Explosives and Excavation Engineering • Course credit load: 2 Series 1: Rock Properties and Drilling Techniques Series outline • Part 1: Rock Characteristics and Drillability o Sub-Part 1.1: Engineering properties of rock material o Sub-Part 1.2: Rock drillability and blastability • Part 2: Theories and Methods of Rock Penetration o Sub-Part 2.1: Classification of drilling and penetration methods
LA-NET | ONLINE LEARNING VIDEO PLATFORM FOR POST-SECONDARY & HIGHER INSTITUTION STUDENTS o Sub-Part 2.2: Theories of rock penetration o Sub-Part 2.3: Rotary, percussive, rotary-percussive, and thermal drilling • Part 3: Drill Bits and Core Recovery o Sub-Part 3.1: Types of drill bits and their applications o Sub-Part 3.2: Diamond drilling and core recovery • Part 4: Bench Drilling Parameters and Equipment Choice o Sub-Part 4.1: Basic parameters affecting bench drilling (bench height, burden, spacing, drilling pattern) o Sub-Part 4.2: Choice of drilling equipment Introduction Drilling into rock is one of the most fundamental activities in mining and excavation engineering. The ability of engineers to predict how rocks will respond to drilling and blasting operations is crucial for achieving efficiency, safety, and cost-effectiveness. By studying the properties of rocks and the techniques used to penetrate them, learners will gain insight into the science and practice that underpin the entire course. The aim of this Series is to equip you with the knowledge and skills needed to analyse rock characteristics, apply theories of penetration, and evaluate drilling methods and equipment choices. We shall commence this Series by examining the engineering properties of rock materials and their influence on drillability and blastability. Next, we will explore the theories and methods of rock penetration, including rotary, percussive, rotary-percussive, and thermal drilling. Following that, we will consider the types of drill bits and their applications, with special attention to diamond drilling and core recovery. Finally, we will wrap up by studying the basic parameters affecting bench drilling and the criteria for selecting suitable drilling equipment. Series Learning Outcomes Upon completing this Series, you should be able to: • SLO 1.1 define the engineering properties of rock material and explain their influence on drillability and blastability, • SLO 1.2 classify drilling and penetration methods and analyse the theories of rock penetration, • SLO 1.3 describe the types of drill bits and demonstrate how diamond drilling facilitates core recovery,
LA-NET | ONLINE LEARNING VIDEO PLATFORM FOR POST-SECONDARY & HIGHER INSTITUTION STUDENTS • SLO 1.4 evaluate bench drilling parameters and apply criteria for choosing appropriate drilling equipment. 1.1 Rock Characteristics And Drillability 1.1.1 Engineering properties of rock material When we speak of engineering properties of rock material, we refer to measurable attributes such as hardness, strength, porosity, and elasticity. These properties determine how easily a rock can be drilled or blasted. For example, hard igneous rocks like granite require more energy to penetrate compared to softer sedimentary rocks such as limestone. The ability to predict these behaviours allows engineers to design efficient drilling operations. Fill in the blank: The ______ of a rock refers to its ability to resist penetration or scratching. Diagram showing comparative hardness of common rock types Caption: Figure 1.1 Comparative hardness of selected rock types 1.1.2 Rock drillability and blastability Drillability is the ease with which a rock can be penetrated by a drill bit, while blastability refers to how effectively a rock can be fragmented by explosives. Both are influenced by rock texture, grain
LA-NET | ONLINE LEARNING VIDEO PLATFORM FOR POST-SECONDARY & HIGHER INSTITUTION STUDENTS size, and natural discontinuities such as joints and fractures. For instance, a rock with many fractures may be easier to blast but more difficult to drill consistently. Fill in the blank: The ease with which a rock can be fragmented by explosives is termed ______. Box 1.1 Factors influencing drillability and blastability
LA-NET | ONLINE LEARNING VIDEO PLATFORM FOR POST-SECONDARY & HIGHER INSTITUTION STUDENTS Pilot questions 1.1 1. Which property of rock material determines its resistance to penetration? 2. Define drillability in your own words. 3. What is blastability and how does it differ from drillability? 4. Name two rock characteristics that influence blastability. 5. Why might fractured rocks be easier to blast but harder to drill? 1.2 Theories And Methods Of Rock Penetration 1.2.1 Classification of drilling and penetration methods Drilling methods can be classified based on the mechanism used to break rock. The most common categories are rotary drilling, which uses continuous rotation of a drill bit to cut rock, percussive drilling, which relies on repeated impacts to fracture rock, rotary-percussive drilling, which combines rotation and impact, and thermal drilling, which uses heat to weaken or melt rock. Each method has advantages depending on rock type, depth, and operational requirements. Fill in the blank: The drilling method that combines rotation and impact is called ______ drilling.
LA-NET | ONLINE LEARNING VIDEO PLATFORM FOR POST-SECONDARY & HIGHER INSTITUTION STUDENTS Diagram showing classification of drilling methods Caption: Figure 1.2 Classification of drilling and penetration methods 1.2.2 Theories of rock penetration The theories of rock penetration explain how energy is transferred from drilling equipment to the rock surface. In rotary drilling, cutting action is achieved through shear stress, while in percussive drilling, compressive stress from repeated impacts causes fracture. Rotary-percussive drilling combines both shear and compressive stresses, making it effective for medium-hard rocks. Thermal drilling applies heat to induce thermal stress, which weakens the rock structure. Fill in the blank: In percussive drilling, rock breakage occurs primarily due to ______ stress.
LA-NET | ONLINE LEARNING VIDEO PLATFORM FOR POST-SECONDARY & HIGHER INSTITUTION STUDENTS Diagram illustrating stress distribution in rotary and percussive drilling Caption: Figure 1.3 Stress distribution in rotary and percussive drilling 1.2.3 Rotary, percussive, rotary-percussive, and thermal drilling Rotary drilling is widely used in soft to medium rocks, where a rotating bit grinds the surface. Percussive drilling is suitable for hard rocks, as repeated hammering fractures the material. Rotary-percussive drilling is versatile, combining rotation and impact to handle a range of rock types. Thermal drilling is less common but useful in specialised applications, such as cutting through extremely hard or brittle rocks, by applying intense heat. Fill in the blank: The drilling method most suitable for soft rocks is ______ drilling.
LA-NET | ONLINE LEARNING VIDEO PLATFORM FOR POST-SECONDARY & HIGHER INSTITUTION STUDENTS Image showing different drilling rigs for rotary, percussive, and rotary-percussive methods Caption:
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