Confining pressure tends to increase rock strength, however in the case of surfaces processes, as for overhanging cliff, the confining pressure is negligible and similar to the values obtained during direct tensile strength experiments. The pore fluid factor includes two aspects: 1) reducing the effective pressure, and 2) chemical interactions ...

"Case study: Using the point load test to estimate rock strength of tunnels constructed by a tunnel boring machine." Bull. Eng. Geol. Environ. 78: 1727–1734. Crossref. Google Scholar. Mishra, D. A., and A. Basu. 2012. "Use of the block punch test to predict the compressive and tensile strengths of rocks."

Olaleye [15] revealed that the higher the strength of a rock, the higher the crushing time under the influence of a crusher; this implies more wear to the crusher jaws. Donovan [9], noted that ...

Crushed stone often has an angular and jagged edge because of the crushing process. Gravel, on the other hand, typically has a very smooth texture and surface because of the natural weathering and …

This paper aims to focus permeability study of self-compacting concrete (SCC) made with industrial wastes, i.e., marble sludge powder (MSP) from marble processing and crusher rock dust (CRD) from stone crushing industries. MSP can be used as filler and it helps to reduce the total voids content in concrete.

The crusher type showed significant effects on the aggregate form. The rock type showed important effects on the texture of coarse aggregate. The effect of the crusher type on the characteristics of shape is more in the marble and less in the tuff aggregates. Aggregate produced from HSI showed a higher cubical form, angularity, …

In rock formations with compressive strength (UCS) ex ceeding 100MPa, roller c ore ba rrels operate by the same "rock crushing" principle as the "down the hole" (DTH) hammer (Figure 5).

The size reduction process of rocks in cone crushers is one of the most important issues, particularly for the secondary and tertiary stages of crushing operations. In this study, 17 different rock types were considered for the evaluation of their size reduction variations that occurred in a laboratory-scale cone crusher. Based on several …

DOI: 10.1016/S1674-5264(09)60185-X Corpus ID: 128621771; Influence of some rock strength properties on jaw crusher performance in granite quarry @article{Olaleye2010InfluenceOS, title={Influence of some rock strength properties on jaw crusher performance in granite quarry}, author={B. M. Olaleye}, journal={Mining …

The shear rate is an important factor that influences the shear mechanical properties of rock joints. In this paper, constant normal load (CNL) direct shear tests at different shear rates ( $${v}_{s}$$ v s = 0.2–5.0 mm/min) were performed on rock joint specimens to investigate the shear behavior and failure modes under various joint …

For metamorphic rock, the crushing of mineral grains occurs at the interlocked boundaries, hence, exhibiting an increase in strength of rock at high loading rates. The second phenomenon of increase in strength deals with the length of the strain pulse that acts on the specimen and is defined in terms of loading duration.

1. Introduction. Rock crushing is the first mechanical comminution process after drilling and blasting operations in rock fragmentation. The energy required for comminution depends on the physicomechanical properties of the rocks and the quantity of materials being crushed [1].Although the use of different crushers should be placed in a …

The crushing time (T c) seems to increase with increasing in rock strength properties. Furthermore, remarkable relationships are obtained between several rock properties and crushability test results.

Finally, using the proposed equation, obtained values were classified along with the different classifications for rock strength and durability. © 2017 The Authors. Published by Elsevier Ltd. Peer-review under responsibility of the organizing committee of EUROCK 2017. Keywords: Strength; Durability; Correlation; Regression; Neural …

• Strength classification is based on strength of the rock (compressive strength & modulus of elasticity; Table 7.2) • 5 strength classes: A-E based on the overall rock strength; A = very strong, E = very weak (Table 7.3) • Any discontinuities, fractures, bedding planes, etc. will strongly influence overall strength of the rock.

Compressive strength of concrete is believed to have a large impact on the energy required for crushing concrete, based on the similar findings for crushing rocks (natural stone) (Korman et al ...

The most important parameters for rock strength evaluations in excavation, mining, and mechanical engineering projects are the uniaxial compressive strength, Brazilian tensile strength, density, abrasivity, and impact strength index. To estimate these parameters, several laboratory investigations and nondestructive methods were …

Reduction in strength and stiffness in rocks attributed to an increase in water content has been extensively researched on a large variety of rock types over the past decades. Due to the considerable variations of texture and lithology, the extent of water-weakening effect is highly varied among different rock types, spanning from …

Therefore, high-efficiency rock crushing can be achieved in engineering . Since the 1980s, ultrasonic resonance has been applied in the field of engineering crushing. ... When the internal cracks are in the …

compression test. As a standard facility for dynamic testing, SHPB consists of a striker bar (200 mm in length), an incident. bar (1600 mm in length), and a transmitted bar (1200 mm in. length ...

Rock joints in faulted zones are usually filled with large amounts of fault gouge, in which clay-rich fillings are very common. Fault water can significantly influence the mechanical parameters of clay-rich fillings and affect the shear mechanical behaviour of rock joints. Based on a tunnelling project passing through a faulted zone in Yunnan …

Berry et al. (1984) determined some rock properties such as compressive and tensile strength, Young's modulus, porosity and attempted to correlate these to the performance of a jaw crusher. Bearman et al. (1991) examined the relation between rock strength and power consumption and product size in crushing.

Strength behavior of jointed rock matrix were then compared with the strength of intact rock specimen. Stress-strain behavior were also compared with Mohr-Coulomb strength theory and Hoek-Brown strength theory. Laterite types of rock was used for present investigation. 2 Sampling.

1 Introduction. In recent years, the fine view research of bulk filling materials has gradually received attention, and the compaction mechanical properties of bulk filling materials as the key factor of rock …

As the rock crushing is essentially a dynamic process in practice, impact tests are more suitable. ... Hiramatsu Y, Oka Y (1966) Determination of the tensile strength of rock by a compression test of an irregular test piece. Int J Rock Mech Min Sci Geomech Abstr 3:89–90. Article Google Scholar Huang S, Xia K (2015) Effect of heat-treatment on ...

1-F Rock Strength Rock Strength Strength is the capacity to sustain (support): Shear stress (shear strength) Compressive normal stress (crushing strength) Tensile stress (tensile strength) Bending stress (bending or beam strength) All of these depend on effective stresses ( σ′), thus, we must know the pore pressure (p or p o)

Cone crushing is a process used in aggregate and mining operations to reduce large pieces of rock, ore, or minerals to smaller sizes. Cone crushing works by squeezing the material between an eccentrically gyrating spindle that is enclosed by a hard outer shell, known as the concave. The material is crushed by being compressed …

By performing single grain crushing tests of granite under both dry and wet conditions, Ham et al. found that the grain crushing strength decrease and the strength variability increase under wet conditions. Similar to the rockfill materials, the properties of rock samples will also deteriorate when subjected to wetting–drying cycles.

The lump test, point load test, crushing tests, impact tests and hardness tests are critically reviewed. The fundamental aspects of importance, namely the dependence of the energy required to break rock on the new surface area created for some processes, and on the test specimen volume for other processes, are considered and shown to be …

Rittinger's theory and law of the energy expended in crushing of rock is that the work of crushing is proportional to the reduction in diameter; or, as I have more fully expressed it: "The work done in crushing is proportional to the surface exposed by the operation; or, better expressed for this purpose, the work done on a given mass of ...