VTechWorks staff will be away for the winter holidays starting Tuesday, December 24, 2024, through Wednesday, January 1, 2025, and will not be replying to requests during this time. Thank you for your patience, and happy holidays!
 

Computer aided blast fragmentation prediction

Simple item page
dc.contributor.authorExadaktylos, George E.en
dc.contributor.committeechairHaycocks, Christopheren
dc.contributor.committeememberKarmis, Michael E.en
dc.contributor.committeememberLuttrell, Gerald H.en
dc.contributor.departmentMining and Minerals Engineeringen
dc.date.accessioned2014-03-14T21:39:45Zen
dc.date.adate2010-07-08en
dc.date.available2014-03-14T21:39:45Zen
dc.date.issued1988-11-15en
dc.date.rdate2010-07-08en
dc.date.sdate2010-07-08en
dc.description.abstractThe complex and non-linear nature of blast fracturing have restricted common blast design mostly to empirical approaches. The code developed for this investigation avoids both empiricism and large memory requirement in order to simulate the pattern of interacting radial fractures from an array of shotholes, at various burdens and spacings, and in simultaneous and delayed modes. The resultant pattern is analyzed and a fragment size distribution calculated. The rules governing the distribution of radial cracks and the way in which they interact are based on model scale experiments conducted by various investigators. Calculated fragment size- distribution agree with data from the field. Powder factor dependence of fragmentation results is also well described by the model. The effect of discontinuities on rock fragmentation by blasting is also incorporated into the model. Discontinuities which are open and filled with air or soil-like material affect destructively the transmission of strain waves and propagation of cracks in the rock mass. These discontinuities can be incorporated into the simulation by inserting cracks to represent them. The cracks representing discontinuities will then terminate the cracks produced by blasting where they intersect. On the other hand, tight joints without filling material or with filling material but with a high bond strength and acoustic impedance close to that of the medium do not affect in a negative way the transmission of shock waves in the rock mass. A mathematical model was developed to treat these discontinuities which was based on principles from Linear Elastic Fracture Mechanics theory and Kuznetsov's equation which relates the mean fragment size obtained to the blast energy, hole size and rock characteristics.en
dc.description.degreeMaster of Scienceen
dc.format.extentix, 113 leavesen
dc.format.mediumBTDen
dc.format.mimetypeapplication/pdfen
dc.identifier.otheretd-07082010-020034en
dc.identifier.sourceurlhttp://scholar.lib.vt.edu/theses/available/etd-07082010-020034/en
dc.identifier.urihttp://hdl.handle.net/10919/43590en
dc.publisherVirginia Techen
dc.relation.haspartLD5655.V855_1988.E933.pdfen
dc.relation.isformatofOCLC# 19298163en
dc.rightsIn Copyrighten
dc.rights.urihttp://rightsstatements.org/vocab/InC/1.0/en
dc.subject.lccLD5655.V855 1988.E933en
dc.subject.lcshBlastingen
dc.subject.lcshRock excavationen
dc.titleComputer aided blast fragmentation predictionen
dc.typeThesisen
dc.type.dcmitypeTexten
thesis.degree.disciplineMining and Minerals Engineeringen
thesis.degree.grantorVirginia Polytechnic Institute and State Universityen
thesis.degree.levelmastersen
thesis.degree.nameMaster of Scienceen

Files

Original bundle
Now showing 1 - 1 of 1
Thumbnail Image
Name:
LD5655.V855_1988.E933.pdf
Size:
3.39 MB
Format:
Adobe Portable Document Format
Download

Collections

Masters Theses