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Full-Text Articles in Explosives Engineering
Effects Of Downwash When Measuring Gas Concentration With Uav-Mounted Gas Sensors, Jacob Lane Brinkman
Effects Of Downwash When Measuring Gas Concentration With Uav-Mounted Gas Sensors, Jacob Lane Brinkman
Doctoral Dissertations
"This research concludes that the downwash region of a rotary-wing unmanned aerial vehicle (UAV) does not produce pressure variations substantial enough to cause significant changes in density-based gas concentration measurements. US regulations evaluate gas concentration as a function of gas density, and accurate concentration measurements are critical for protecting health and safety, which means evaluation of actual downwash effects on measured gas concentration is essential.
During experimentation, the UAV was fixed to a stand in a sealed chamber filled with NOx (NO and NO2) of constant concentration. The UAV rotors ran at hovering speeds, and gas concentrations were …
The Mechanics Of Precision Presplitting, Anthony Joseph Konya
The Mechanics Of Precision Presplitting, Anthony Joseph Konya
Doctoral Dissertations
"Precision Presplitting is a widely used method of presplit blasting for the mining and construction industries. In recent years considerable effort has gone into the development of empirical equations based on field data to be able to better design the Precision Presplit for various rock types and structural environments. However, the most widely discussed theory about the mechanics of the presplit formation, that of shockwave collisions, does not appear to be applicable for this method of presplitting.
This research has disproven this theory based on insufficient magnitude of the shockwave from modeling with basic wave mechanics. Other authors have suggested …
The Influence Of Caprock On Blast Fragmentation Distribution, Matthew Kurtis Coy
The Influence Of Caprock On Blast Fragmentation Distribution, Matthew Kurtis Coy
Doctoral Dissertations
"This dissertation describes the development of a small-scale model of a caprock-laden quarry blast and discusses the results from that testing. The purpose of this testing was to provide insight into the reasons for poor caprock breakage during blasting.
Small-scale test blocks were poured using a weak mortar mix to represent a limestone formation at a small scale. A cold joint was created in the upper portion of the test specimens to represent the bedding plane that separates caprock and substrate layers in a caprock-laden limestone bench. The scale-model test blocks were blasted using detonating cord. The primary configuration for …