By evaluation of the blasting results, a proper blast pattern can be presented. It is, therefore, essential to employ a reliable method to evaluate blastings for the effective control and optimization of the main cycle operations. This paper aims to propose a criterion for evaluating the blasting results such as the fragmentation, muckpile condition, back-break, and fly rock, and to make a poss...

The controlled presplitting blasting technique is widely used in mining engineering to improve the permeability and gas extraction efficiency of coal seams. One of the key factors is the appropriate arrangement of the blasting and drainage holes, which can help improve the gas drainage quantity. To optimize the drilling layout to enhance gas-drainage efficiency, a series of controlled presplitt...

Trial blasting is conducted to identify the characteristics of the blasting of the applicable ground before production blasting and to investigate various problems posed by blasting. The methods and pattern of production blasting are determined based on an analysis of the results of trial blasting. The bedrock in Jeju Island, South Korea is formed through the volcanic activities unlike the inla...

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...

OBJECTIVE Polyaxial pedicle screws are a safe, useful adjunct to transpedicular fixation. However, the large screw head size can cause soft tissue irritation, high rod positioning, and facet joint injury. However, the mechanical resistance provided by small and low profile pedicle screws is very limited. We therefore developed a novel, low profile pedicle screw using grooving and blasting treat...

Adhesion strength of exterior or interior coating of steel pipes is too important. Increasing of coating adhesion on surfaces can increase the life time of coating, safety factor of transmitting line pipe and decreasing the rate of corrosion and costs. Preparation of steel pipe surfaces before doing the coating process is done by shot and grit blasting. This is a mechanical way to do it. Some e...

This study investigated the feasibility of the micro powder blasting technique for the micro fabrication of sensor structures using the Pyrex glass to replace the existing silicon-based acceleration sensor fabrication processes. As the preliminary experiments, the effects of the blasting pressure, the mass flow rate of abrasive and the number of nozzle scanning times on erosion depth of the Pyr...

Exotic semiring constraints arise in a variety of applications and in particular in the context of automated termination analysis. We propose two techniques to solve such constraints: (a) to model them using Boolean functions and integer linear arithmetic and solve them using an SMT solver (QF LIA, in certain cases also QF IDL); and (b) to seek finite domain solutions by applying unary bit-blas...

Ground vibration is one of the undesirable results of blasting operations. Different methods have been proposed to predict and control ground vibration that is caused by blasting. These methods can be classified as laboratory studies, fieldwork and numerical modeling. Among these methods, numerical modeling is the one which saves time and cuts costs since it takes into account the basic princip...

In order to understand the stress changes of various points in sandy frozen soil, tension-compression conversion, fissure development on the surface, the rupture process, the expansion speed and scope of frozen soil duing blasting, the dynamic characteristics of thin-layered sandy frozen soil were analyzed in this paper. The blasting process of frozen soil is regarded as a dynamic pressure oper...