crushing hard rock without blasting

Hard rock excavation without blasting for civil …

An unconventional alternative process is the application of electrohydraulic …

Blast Hole Pressure Measurement and a Full-Scale Blasting …

The feed size of the jaw crusher operating in the A-aggregate mine requires a rock fragment size of at least 1000 mm or less. Therefore, to input the jaw crusher for primary crushing, it is necessary to perform secondary work on fragments by hydraulic rock breakers after blasting the rock, which incurs additional costs.

Review of Empirical and Intelligent Techniques for Evaluating Rock

Blasting for breaking hard rock is a well-known economical way for civil engineering and mining projects for more than 70 years. Desired good fragmentation is the most important result of any blasting operation which has a direct impact on efficiency and productivity of downstream operation such as loading, transport, crushing, and milling ...

Development of low noise and vibration tunneling

In the case of the blasting method, the crushing force is strong and excavation has become possible even with a free face as the center cut blasting has been devised. However, the crushing capacity of the rock fracturing method is less powerful than blasting, and crushing with one free face is impossible.

RESEARCH ARTICLES Impact of blast design parameters …

up to 500 mm size and hence, the size distribution of rock mass by the process of blasting plays an important role in deciding the economics of not only stone mining opera-tions but also front-end beneficiation using a crushing system. The extent to which rock is broken into small pieces by blasting is known as fragmentation9. The full spectrum of

Precision Rock Excavation: Beyond Controlled Blasting and …

Correlation between the energetic cost of excavation of the rock, expressed in CV h/t, and the average size of the fragments obtained, expressed in inches. The "ranges" designate: "Blast Hole Drilling": drilling of blast holes; "Boring Machines": machines for the mechanical excavation of tunnels or shafts; "Explosives": blasting.

Assessing and controlling of boulder deep-hole blasting …

Some researchers analyze the blasting scheme and unit explosive consumption of boulder blasting without free surface in the shield tunnel ... and the hard rock in a certain area is crushed by the ultra-high pressure impact load. Since the crushing area is constrained by solid rock and most of the rock mass has high dynamic …

ROCK FAILURE Air Decks in Surface Blasting Operations

blasting, an air gap is introduced in the explosive column, which helps in distributing the explosive energy effectively throughout the rock mass. In this way, a uniform rock breakage is ensured and a loss of energy through the excessive crushing that occurs near the charge is avoided [4]. Air deck blasting started as far back as 1893 [5, 6].

Quarrying of Stones: Its Methods, Selection of …

Quarrying of Stones. Definition: Stones occur in the form of natural rock masses or layers on the surface. The process of extraction of suitable stones from their natural rock beds or layers is commonly called …

Study on Mechanism of Static Blasting-Induced Hard Rock …

How to deal with hard rock cheaply and safely is a pressing issue in today's coal mining. Weakening fractures of hard rock have always been a significant concern in China's coal mine engineering. In this study, mechanical derivation, laboratory experiments, and numerical simulation research methodologies are used to evaluate the fracturing …

Environmental impact assessment (EIA) of hard rock …

The increase in demand of building stones and construction-grade sand has resulted in aggressive hard rock quarrying in many parts of the world. The problems are to be evaluated in detail for the judicious use of resources on the one hand and ensuring health of the ecosystems on the other. The present study aims to evaluate the impact of hard …

SciELO

Tunneling in hard rock is hard to imagine without using explosives for rock excavation. In the case of this excavation method, the surrounding rock mass that represents the tunnel walls is damaged by blasting. ... The impulse from an explosion and conditions for its greater utilization in crushing hard rock masses in blasting.: Soviet Mining ...

Alternatives to drilling and blasting | Aggregates Business

The drill and blast method is used in many quarries to win stone for …

A Method for Making Transparent Hard Rock-Like Material and

At present, a similar material most commonly used in the similarity model experiment of rock blasting is cement mortar. However, it is not transparent, which leads to the problem that the cracks in the model made of cement mortar after the test cannot be observed directly. Therefore, a kind of transparent hard rock-like material that can …

Break hard rock without blasting

It adopts non-explosive method to crush rocks, which has the advantages of small …

Crushing Hard Rock Without Blasting

Crushing Hard Rock Without Blasting pallradde. Crushing Hard Rock Without Blasting Many times excavation in rocks are required for foundation of structure The procedure for excavation in rocks is different than excavation in ordinary soils It requires skilled manpower and specialized tools and equipments for excavating the rocky ground ...

P&Q University Lesson 4- Drilling & Blasting | Pit & Quarry

Blasting is heavily regulated and watched by federal, state and local agencies. In terms of processing, blasting is the critical first step in the rock-fragmentation process. Maximum profitability depends largely on an optimized blast. Consider that drilling and blasting are the first operations performed in any hard rock quarry operation.

Study on blasting characteristics of rock mass with weak …

When blasting in hard rock and the distance between weak interlayer and blast hole is within about twice the radius of crushing area, the damage degree of rock mass around blast hole is higher ...

A review of some nonexplosive alternative methods …

This review discusses some nonexplosive rock breakage methods, particularly the …

(PDF) Analysis of blasting characteristics of interbedded rock …

(iii) For hard rock environments with layer thicknesses up to 3 times the radius of the crushing zone, the number of cracks increases with layer thickness at a rate of 68% per meter, conversely ...

PAPER OPEN ACCESS Without Fly Rock Blasting …

allows to improve significantly the quality of rock crushing. This is achieved by increasing the explosion duration and the height of the charge column with a corresponding decrease of tamping length. Thus the explosive ratio decreases in hard-crushed rocks by 8-10 %, and in easy- and medium-crushed rocks – by 18-20 %.

COMPARISON OF NON-EXPLOSIVE ROCK …

As there are not the crushing effects of compressive breakage as with explosives, dust …

(PDF) Rock breaking methods to replace blasting

Sensitive blasting technology, commonly known as non-explosive (nonex) rock-breaking methods, are starting to gain attention …

Hard Rock Excavation without Blasting for Civil Engineering …

Excavation without blasting is the present need of technological …

380+ Jaw Crusher Stock Photos, Pictures & Royalty-Free …

Jackhammer using without blasting method. Hard rock demolition Excavator with hydraulic breaker hammer for the destruction of concrete and hard rock at the construction site or quarry. Jackhammer using without blasting method. Hard rock demolition jaw crusher stock pictures, royalty-free photos & images

Drilling and Blasting

Optimum Fragmentation. Zong-Xian Zhang, in Rock Fracture and Blasting, 2016. 21.5.2 To Increase Explosive Energy in Blasting. The preceding analysis indicates that an increase in drilling and blasting energy can increase the efficiency of total energy in the whole size reduction system. Moreover, a total of 210 blast tests show that the …

Research on the damage characteristics of rock masses …

In the study of hard rock guide hole blasting, it is found that when the distance between the gun hole and the empty hole is 1.2 m and 1.6 m 23,24, the crack penetration effect is good, which is ...

Drilling and blasting designs for parallel hole cut and V-cut …

The rock mass characteristics in the region are variable and the average RQD (Rock Quality Designation) is around 90% in medium hard formations which contain massive sandstone while this value is ...

A review of some nonexplosive alternative methods to conventional rock

The conventional blasting rock excavation method is the main means of rock breakage because of its high productivity, and it is relatively inexpensive compared to other methods. However, it raises safety concerns and can negatively impact the environment. The major disturbances that may be induced by this method include flyrock, gas emissions, and …

Removing Rocks Without Blasting | JLC Online

The procedure recommended by manufacturers is simple: With a rotary hammer, you drill holes of roughly 1 1/2 inches in …