The mechanics of presplitting in discontinuous rock onepetro. This reference may be obtained free of charge in adobe acrobat pdf format through the fhwa at the following. Blast plan a written procedure that details the methods and manner by which a project blaster. Osmres business practices are to reclaim abandoned mine lands title iv, regulate active coal mines title v, and apply sound science through technology transfer. Control blasting, mining, rock fragmentation, presplitting, blast damage. Furnish contract bonds within 10 days after receiving notice of award. Modeling explosiverock interaction during presplitting. A master plan of the presplit holes position at spacing of 1. Download presplitting or read online here in pdf or epub.
Governments official website for the office of surface mining reclamation and enforcement osmre. Overview yardportable, versatile blast machine that removes contamination, corrosion, mill scale, and coatings from most surfaces. Presplitting is carried out in both transitional fig 2 and fresh rock fig 4, with trim blasting employed to further reduce the damage to the walls. Bulk explosive and shock tube initiation was normally used in mines. Dangers of toxic fumes from blasting centers for disease. K, holmes and refined by others 2,3 consists of drilling a series of 2 to 3inchdiameter holes. Hustrulid2 1, 2 niosh, office of mine safety and health research, 315 e. Breakage diagram for presplit in jointed rock after worsey. This study was undertaken to determine the magnitude of ground vibrations produced by traffic andor construction blasting. Presplitting creates a fracture plane along the final slope face, which prevents the radial cracks created by production blasting from penetrating into the finished face.
The crack helps to screen the surroundings from ground vibrations during the firing of the main round. Damage was measured using various techniques including. Pdf optimizing presplit blasting for environmental control and pit. To receive documents or other information about occupational safety and health topics. Very few email service providers provide the ability to attach a pdf file or other file attachments. Study on air, water deck in presplitting and rock blasting. Arbitrary lagrangian eulerian ale computational techniques allow treatment of gases, liq uids, and solids in the same simulation. Technical inormation product disclaimer dyno nobel inc. This is especially true where specifications call for. Overview yardportable, versatile blast machine that removes contamination, corrosion. Pdf presplit blasting is commonly practiced in open pit mines to create shear planes on in situ rock. Initiations and timing effects as well as patterns are also discussed. This site is like a library, you could find million book here by using search box in the widget. Blast pattern the plan view of the drill holes as laid out for blasting.
Appendix j blasting protocol tim miller associates. Controlled blasting techniques include presplitting, cushion blasting, and sliver cut blasting. This manual was designed to provide a systematic approach to surface blast. Line drilling is used mostly in small blasting operations and involves small holes in the range of 50 100 mm in diameter. These tests indicated that it is easier to fracture the rock parallel to the. Based on the parameters of blasting, explosive and coal bed achieved from the mines, the mechanism of the presplitting blasting in coal body is studied by threedimensional numerical simulation. Soundwall blasting met by the technique of presplitting, developed in the united states in the late 1950s. The primary objectives of this study were to determine a recommendation for the preblast area for surveys, and to obtain actual field vibrations from rock blasting operations, in populated regions within specific geologic units. Parameters for drilling in a presplit blasting operation modified from u. In this paper is presented a description of several problems associated with highway blasting that continue to recur with undesirable results.
Such information could provide a tool in defense of legal claims concerning physical damage to nearby properties. Assessment and application of a singlecharge blast test. Dec 17, 2009 following are the techniques of controlled blasting. Directional presplit blasting in an innovative nopillar mining approach. Optimizing presplit blasting for environmental control and pit wall stability conference paper pdf available august 2016 with 2,406 reads how we measure reads. Meanwhile in sweden, presplitting is a major part of the operation at the aitik mine with roc rigs doing the presplitting work and pit viper rigs taking care of the production hole drilling. Cushion blasting fhwa us department of transportation.
The aesthetic aspect of a presplit should not bia judgment on the effi ciency of this technique, if sufficient can be with modified production blasts, the need for smoothwall blasting or presplitting can be reduced. Just upload files you want to join together, reorder them with draganddrop if you need and click join files button to merge the documents. Blasting protocol stateline retail center february 2007 blasting is expected to be necessary at several locations along the southern boundary of the property, adjacent to interstate 84, for the construction of some of the several building pads on the property. Rearrange individual pages or entire files in the desired order. Application recommendations minimum detonating cord is 5. Basically, this technique consists of creating a continuous crack or presplit at a desired finished excavation line by initially firing a line of closely spaced, lightly loaded holes drilled there. Assessment and application of a singlecharge blast test at. Pdf documents are often used because they help preserve the original content of the document, but this can make splitting the file up a little more difficult than other document formats.
The main objectives of presplitting in open pit mining are find, read. Ale codes can also treat explosive detonation and the expansion of the explosive. A new, faster, interactive 3d engine with enhanced textures, transparency, lighting and rotation. In addition messages with attachments are more likely to get flagged as spam, be blocked or go right to the junk box. Example showing drill hole locations of a successful blast design in australia that. Normal production blast consists of detonation of 68 rows involving 140200 holes in a blast round. Presplit blasting, or presplitting, is used before production blasting to protect the final rock face from damage caused by the production blasting. Pdf optimizing presplit blasting for environmental. Presplit blasting is a technique used to reduce damage to excavation profiles during blasting by preforming a continuous fracture between parallel boreholes lightly charged with decoupled explosives along the line of the required. Each type of blastingpresplit, smooth, and cushion blastinghas its own formula. Modeling explosiverock interaction during presplitting using. Rock blasting consists of drilling holes in a rock mass at depths, in. Introduction presplit blasting is a technique used to reduce damage to excavation profiles during blasting by preforming a continuous fracture.
Presplitting is the creation in solid rock of a fracture plane with pre determined direction and extent by the proper use of explosives and drill holes. Here, 165 mm presplit holes are drilled at 20 degree angles on 33 m double benches. Bender 1999 defined production blasting as the type of blasting that is designed to fragment a predetermined volume of rock. Smooth blasting is a type of controlled blasting thats done either before production blasting, as an alternative to presplitting, or afterwards, either as an entirely different event or as the last delay of the production blast. The purpose of this blasting plan is to outline the steps that will be employed when conducting any blasting associated with tdinew englands tdine proposed new england clean power link project necpl. Presplitting or preshearing can be defined as the establishment of a free surface or shear plane by the controlled use of explosives and blasting accessories in. Presplit blasts are carried out in advance of trim blasting. A study was conducted to evaluate the effect of air deck pipe deck, water deck technique to control induced ground vibration in production blasting and presplitting at tata west bokaro, colliery. This protocol is prepared as an outline specification for blasting operations as. Blasting is considered as the first step in the mineral supply chain in most of the mines.
All books are in clear copy here, and all files are secure so dont worry about it. Jul 24, 2015 this feature is not available right now. Presplit blasting is required on state row when the design rock slope is one vertical on one. Konya this is the first in a twopart article about precision presplitting. Mining issues the design wall angles vary around the pit from to 85. An ideal blast results in a minimum of damage to the host rock with minimum of overbreak. Suggestions are offered for handling such problems so as to mitigate or eliminate their impacts on future projects. To view pdf files download the adobe acrobat reader.
Cushion blasting, smoothwall blasting, presplitting, and light blasting combined with line drilling are examples of controlled blasting techniques. The landbased segments of the necpl that may involve blasting include. The spacing is kept closer than buffer holes and production holes. Perimeter or contour holes are drilled along specified final excavation limits and are lightly loaded than that of buffer holes and production holes. Preliminary tests on presplitting rock in the presence of an in situ static stress field were undertaken to study the influence of a horizontal static stress field on the creation of a vertical presplit fracture plane. Through the use of presplitting of the perimeter row one. The findings and conclusions in this report are those of the authors and do not necessarily represent the views of the national institute for occupational safety and health. Dynosplit is designed for presplitting or cushion blasting in surface operations and for smooth wall, contour or trim blasting underground. The study was aimed at optimization of blast parameters to enhance over all blasting efficiency in quarry by using explosive. Pdf permeability enhancement of deep hole presplitting. Once the crack is made, it screens off the surroundings to some extent from ground vibrations in the main round. Methods, such as line drilling, presplitting, cushion blasting, fracture control blasting, and smooth blasting are successfully used in civil.
Presplit blasting presplit blasting is an effective technique for stabilizing the final wall in open pit metal mines. Box 380, hagerstown, md 21740 n recent years, shot blast cleaning systems have replaced other mechanical or. The 115mm diameter holes are drilled over two benches 10m, with the top bench drilled at the design wall angle and the bottom bench drilled 5 degrees steeper to allow for drill mast access. The most common approach to final limit blasting is to spec. The latter technique has become the most widely used in metal open pit mines, due to good results and its operational nature in hard rock formation.
Special provision 110 003 excavation for this project, item 110, excavation, of the standard specifications, is hereby amended with. The mechanics of presplitting in discontinuous rock. Line drilling, trim cushion blasting, smooth contour or perimeter blasting, presplitting, selecting and employing various parameters of blast design, using modern technology, precise and accurate timing delays, muffle blasting at critical and congested areas. The preferred method for sending pdfs is to get setup with an email service provider, upload the pdf to a web server and then provide a link inside the email. Import surface files from sources such as xyz, xml, carlsons tin or point cloud scans to begin the design. In addition to rock fragmentation, blasting has a significant role in exerting inner damage and reducing. For safe, efficient blasting, read and follow the operations manual and seek training for everyone who will use this equipment. This special provision covers the following items of work. Pdf design of controlled blasting presplitting in golegohar iron. Special provision 110 003 excavation for this project, item 110, excavation, of the standard specifications, is hereby amended with respect to the clauses cited below, and no other clauses or requirements of this item are waived or changed hereby. Pdf presplitting is a controlled blasting technique with applications in open pit mines. Directional presplit blasting dpb technology for an innovative nopillar mining approach is introduced.
By implementing controlled blasting, perimeter damage can be minimized and underground safety improved. In an attempt to control the fracture of the rock along the slope line, presplitting is often required on many rock cuts. Presplit blasting is commonly practiced in open pit mines to create shear planes on in situ rock slope to ensure pit wall stability, and also protect nearby structures against blast damage. Presplitting a controlled blasting technique for rock cuts. The findings and conclusions in this report are those of the authors and do not. Binary explosive a blasting explosive formed by the mixing of two plosophoric materials, for example, ammonium nitrate and nitromethane. Introduction presplit blasting is a technique used to reduce damage to excavation profiles during blasting by preforming a continuous fracture between parallel boreholes lightly charged with decoupled explosives along the line of the required surf. The computer program controlled blasting is designed to consider presplitting, trim cushion blasting, line drilling and air deck methods for wall control. Rock blasting and control overbreak fhwa us department of.
Office of surface mining reclamation and enforcement osmre. Following are the techniques of controlled blasting. Delayed blasting tests to improve highwall stability a. Box 380, hagerstown, md 21740 n recent years, shot blast cleaning systems have replaced other mechanical or chemi cal metal surface preparation processes. The mechanics of presplitting in discontinuous rock authors p. Ale methods include the ability to treat shockwaves in gases, liquids, and solids and the interaction of shockwaves with each other and with media from one of the other categories. The program uses basic information and state of the art design formulas to determine powder loads, bottom loads, stemming distances and spacing for different methods of controlled blasting. Pdf optimizing presplit blasting for environmental control.