Systematic Drilling and Blasting for Surface Excavations Part 12 pps

... H. The values of H and ~ dll, in general, be different for each component of peak particle velocity (radial, vertical, and transverse). After determining the values of H and p for one specific ... typical example of data for peak particle velocity versus scaled distance for one particular site is shown in Fig. 7-5. Note that the data for each component of peak particle velocit...

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... on the density, ingredients (Fig. 3-3), particle size, charge diameter, and degree of confinement. Decreased particle size, increased charge diameter, and increased confinement all tend to increase ... (60) 180. 190- 200. 210. Fig. 3-2. Nomograph for comparing weight strength and cartridge strength6 3-3 EM iiiO-2-3800 i Mar 72 (5) Usually dynamites are rated on weight strength and g...

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... largely replaced dynamites and gelatins in bench blasting. Denser slurry blasting agents are supplanting dynamite and gelatin and dry blasting agents. 3-16 E,M ili O-2-3800 i Mar 72 . excavation blasting in ... will disperse relatively rapidly and uniformly. (4) Inadequate priming imparts a low initial detonation velocity to a blasting agent, and the reaction may die out a...

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... Manual 1110-2-3800 Department of the Army U.S. Army Corps of Engineers Washington, DC 20314-1000 EM 1110-2-3800 1 March 1972 Engineering and Design SYSTEMATIC DRILLING AND BLASTING FOR SURFACE EXCAVATIONS Distribution ... Secondary Blasting Coyote Blasting, Trenching, and Cratering Underwater Blasting Underwater Surface Shooting Underwater Blasting in Drill Ho...

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... for the future. The drilling and blasting manual for surface exca- vations is the first of this series. Selected references that describe drilling and blasting procedures and results as well ... second (fps) and in strong rock with little jointing, it will travel as fast as 20,000 fps. P- and S-waves perform work by moving the rock particles Longitudinally and transv...

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... quartz content and the porosity12 (Figs. 4-2 and 4-3) are useful parameters for estimating drillability. c. Analysis of the mechanics of drilling systems reveals limita- tions of each and indicates ... The marked insensitivity to external shock and friction makes a detonating fuse ideal for both down lines and trunk lines for primary blasting. Since the blasting cap need...

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... Mar 72 CWPTER,5. BASIC SURFACE BMTING TECHNIQUES 5-1. Introduction. a. Rock blasting may be conducted for removal of rock, for con- trol of excavated rock surfaces, and for control of blasted ... techniques used for surface excavations. Information was obtained from CE District offices and projects supplemented in less familiar procedures by references 8 and 14. 5-2. Bla...

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... retain gases and reduce noise and flyrock. Table 5-1. Charge Concentration of Inclined Holes (i) for Single-Row Bench Blasting for Fragmentation with Respect to Various Burdens and Hole Diameters ... airblast, and breakage with a drop ball is pre- ferred wherever that equipment is adequate and available. b. Coyote Blasting, Trenching, and Crate ring. (1) Coyote blasting (...

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... the bottom and for close hole spac- ing should be much less. (2) Relation to Main Blast. Presplitting and primary blasting are sometimes performed in one operation with the presplit and pri- mary ... iiiO-2-3800 i Mar 72 Table 5-3. Some Typical Hole Spacings and Diameters, Charge Concentrations, and Burdens for Smooth Blasting (after Langefors and Kihlstr6m14) Drill Hole C...

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... heav- ing effect for loosening and moving material. (2) Presplit blasting for a finished rock surface may be more difficult in highly fractured rock depending partly on the nature and atti- tude ... compressive and tensile strengths for a selected group of rocks with divergent properties. (2) Fig. 6-2 is an empirical chart useful for estimating blasthole spacing and size...

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