Systematic Drilling and Blasting for Surface Excavations Part 6 docx

... 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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... Paragraph 6- 3c 6- 3c(I) 6- 3c(2) 6- 3d 6- 3e 6- 4 6- 4a 6- 4b 6- 4c 6- 4d 6- 4e 6- 5 6- 6 7-i 7-2 7-2a 7-2b 7-2c 7-2d 7-3 7-3a 7- 3b 7-3C 7-3d 7-3e 7-4 8-i 8-la 8-lb 8-2 8-2a 8-2b 8-2c 8-2d 6- 7 6- 8 6- 9 ;:;1 6- i2 6- i2 6- i3 6- 13 6- ... 5-5a 5-5b 5-5C 6- i 6- 2 6- 2a 6- 2b 6- 2c 6- 2d 6- 3 6- 3a 6- 3b 5-3 5-4 5-4 5-4 5-5 5 -6 5-8 5-11 5-ii 5-12 5-12 5-i3 5-...

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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 ... Distances for Storage of Explosives, 1 964 , Pamphlet 2 Do’s and Don’ts, 1 964 Radio Frequency Energy, i 968 , Rev Ed., Pamphlet 20 c. A series of CE engineer manuals on rock...

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... from and calculated particle velocities damage criterio~ for unlined tunnels explosion is about 20 ips for the Table 7-1. Strain and Particle Velocity at Failure for Five Rocks Dynamic Particle Breaking Propagation Velocity Strain Velocity at ... was 14,500 fps and in sand- stone was 7,400 fps. Using the relation V=EC the particle velocity v for damage to occur in unlined tunnel...

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... Velocity Water 6 /0 To Gravity fps Resistance Fume Class Cartridge Count Straight Nitroglycerin Dynamite 60 50 40 30 20 60 50 40 30 20 65 65 65 65 65 65 65 65 65 65 65 65 65 65 60 50 40 30 20 52 45 35 25 15 1.3 ... 1.0 7,500 Poor Fair 135 35 i.o 7,200 Poor Fair i4i 30 0.9 6, 900 Poor Fair i53 25 0.9 6, 500 Poor Fair 163 20 0.8 6, 300 Poor Fair 174 Note: Values shown...

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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 ... Dynamite Nitroglycerin 12.0 i2 .6 i6.5 16. 7 22.5 Sodium nitrate 57.3 46. 2 37.5 25.1 15.2 Ammonium nitrate ii.8 25. i 31.4 43.1 50.3 Carbonaceous fuel io.z 8.8 9....

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... 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 not be connected into ... 72 SOFT ROCK BIT -FOR CLAY, SHALE, SALT, GYPSUM, CHALK, AN HYORITE, AND MEDIUM LIME ROCK. MEDIUM ROCK BIT - FOR LIME- STONE, DOLOMITE, HARD SHALE, AND AN HYDRITE. HARD ROCK BIT -...

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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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... 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 Charge Con- Burden (thick- Diameter centration ... plane should not be greater than 6 in. at the bottom and for close hole spac- ing should be much less. (2) Relation to Main Blast. Presplitting and prim...

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... Type fps lb/see/in. f Granite i8,200 54 Marlstone ii,500 27 Sandstone 10 ,60 0 26 Chalk 9,100 22 Shale 6, 400 i5 and, therefore, good coupling possibilities. 47) and granite (impedance 54) also suggest plosive energy. Characteristic impedances 6- 3 (Coumesy ... compressive and tensile strengths for a selected group of rocks with divergent properties. (2) Fig. 6- 2 is an empirical...

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