feJ-aJ Référença M F* ¿~- -2 * Reference IF DEPARTMENT OF THE ARMY FIELD MANUAL r1 s~ í ', « ; EXPLOSIVES AND DEMOLITIONS Return to Army Library Room 1A522, Pentagon HEADQUARTERS, DEPARTMENT OF THE ARMY ^»¿tawBiAnij MAY 1959 »m 1A518, Penta^n Washington, D.C. 2031Ö» * FM 5-25 FIELD MANUAL HEADQUARTERS, DEPARTMENT OF THE ARMY, No. 5-25 WASHINGTON 25, D.C., 14 May 1959 EXPLOSIVES AND DEMOLITIONS Paragraphs Page CHAPTER 1. INTRODUCTION Section I. General 1,2 3 II. Principles of explosives 3-6 3 CHAPTER 2. MILITARY EXPLOSIVES Section I. Demolition blocks and cratering charges 7-15 7 II. Shaped charges and bangalore torpedoes 16-18 14 III. Package charges and pole charges — 19-21 20 IV. Limited standard explosives. 22-25 21 V. Foreign explosives 26,27 24 CHAPTER 3. SAFE HANDLING AND STORAGE OF EXPLOSIVES Section I. Handling precautions 28-35 25 II. Transportation and storage safety precautions 36-43 28 CHAPTER 4. DEMOLITION EQUIPMENT Section I. Blasting equipment and accessories 44-62 32 II. Demolition sets and kits. 63-67 65 CHAPTER 5. CHARGE FIRING SYSTEMS AND THE HANDLING OF MISFIRES Section I. Nonelectric firing systems 68-77 69 II. Electric firing systems 78-93 80 III- Detonating-cord firing systems 94-105 94 IV. Dual firing systems -- .106-109 105 CHAPTER 6. CALCULATION AND PLACEMENT OF CHARGES Section I. General 110-112 108 II. Steel-cutting charges 113-116 111 III. Timber-cutting charges 117-119 117 IV. Pressure charges 120-123 123 V. Breaching charges. 124-127 .127 VI. Cratering, ditching, and land clearing 128-137 131 CHAPTER 7. CONSIDERATIONS AND METHODS FOR DEMOLITION PROJECTS 138-142 142 8. BRIDGE DEMOLITIONS Section I. Major considerations in bridge demolitions.. 143-147 151 II. Specific bridge demolitions 148-157 158 »This manual supersedes FNVS^S, 2 Scpumher 1954 and TC 5-4, 8 November 1957. Paragraphs Page CHAPTER 9. DISRUPTION OF TRANSPORTATION AND COMMUNICATIONS SYSTEMS Section I. Lines of transportation 158-164 173 II. Communications systems 165-167 181 CHAPTER 10. DESTRUCTION OF EQUIPMENT AND SUPPLIES _ 168-175 182 11. DESTRUCTION OF BUILDINGS AND INSTALLATIONS 176-180 185 APPENDIX I. REFERENCES 187 II. POWER REQUIREMENTS FOR MULTIPLE FIRING CIRCUITS 188 III. USE OF LAND MINES, AERIAL BOMBS, AND SHELLS AS DEMOLITION CHARGES 198 IV. SUMMARY OF FORMULAS FOR EXPLOSIVES... 200 INDEX 203 CHAPTER 1 INTRODUCTION Section I. GENERAL 1. Purpose This manual provides information and guidance for all personnel engaged in training for, or conducting, demolition operations. 2. Scope This manual discusses the types, characteristics, usage, handling, storage, transportation, and safety precautions of explosives and demo- litions equipment. The preparation, calculation, placement and firing of charges, along with appropriate formulas, are described and illus- trated. Deliberate and hasty demolition procedures suitable for use in the forward combat zone are outlined. The material presented herein is applicable to both nuclear and nonnuclear warfare. Section II. PRINCIPLES OF EXPLOSIVES 3. Definitions a. Explosive. Substance which, when subjected to heat, impact, fric- tion, or other suitable initial impulse, undergoes a very rapid chemical transformation, forming other more stable products entirely or largely gaseous, whose combined volume is much greater than that of the original substance. b. Demolitions, Military. The destruction by explosives, fire, water, mechanical or other means, of structures or materials as a matter of military necessity or expediency. 4. Classification of Explosives Explosives are classified as low explosives or high explosives accord- ing to the speed (expressed in feet per second) at which the change of state takes place. a. Low Explosives. Low explosives, such as black powder and smoke- less powder, change from a solid to a gaseous state relatively slowly. The reaction causing this change is called deflagration. A deflagrat- ing explosive is one that burns progressively over a relatively sustained period of time, and this action can be utilized to push or shove, rather 3 than to rend and tear, the object against which it is placed. The principal military use of the low explosive is as the propelline; charfife for a projectile and for powder trains such as in a time fuze. /;. High Explosives. High explosives, such as TNT and dynamite, change from a solid to a gaseous state almost instantaneously. The reaction causing this change is called detonation. A high explosive is detonated by heat or by shock, which sets up a detonating wave. This wave passes through the entire mass of the explosive almost in- stantaneously, changing the explosive from a solid to a gaseous state. The sudden generation of gases and their extremely rapid expansion produces a shattering effect which can overcome great resistance in their path. The velocity of detonation of an explosive is the rate, in feet per second, at which the detonating wave travels through a col- umn of the explosive. The principal military uses of high explosives are to execute all types of engineer demolitions, and to provide the charges in high explosive shells and bombs. Principal types of high explosives for military purposes are included in table I. g. Oosocedl [^©¡pertäes ®{F IMWMmy EK|¡3D®SíV©S The desirable properties of military explosives are as follows: a. Relative insensitivity to shock or friction; not liable to detonation by small arms fire. b. Proper detonating velocity for intended purposes. c. High power per unit of weight. d. High density (weight per unit of volume). e. Sufficient stability to retain usefulness for a reasonable time in any climate. f. Positive detonation by easily prepared primers. g. Suitability for underwater use. h. Convenient size and shape to facilitate packaging and logistics and handling by troops. (ai. (PromsópsaO MoDctey tEnptesäves The principal types of explosives commonly used for military pur- poses are shown in table I. The table indicates the principal uses of these explosives; however, they may be used for other purposes when necessary. ïn using the table to determine the proper type of explo- sive to be employed for a specific purpose the velocity of detonation should be considered. Explosives with a high velocity of detonation are generally used for cutting and breaching, while those with a lower velocity of detonation are used for cratering, ditching, and quarrying. Table I. Charaderistics of Principal United Stales Explosives Relative Smallest cap required for Velocity of effectiveness Intensity of Niiino Principal use detonation Detonation as external poisonous fumes Water resistance /ft per sec) charge (TN'T-1.00) TNT 21,000 1. 00 Dangerous Excellent Main charge, booster Tetrytol charge, cutting and 23, 000 1.20 Dangerous Excellent breaching charge, Composition C-3 general and military Special blasting cap. 26, 000 1.34 Dangerous Good use in forward areas. electric or Composition C-4 nonelectric. 26, 000 1.34 Slight Excellent Ammonium Nitrate Cratering and ditching 11,000 0. 42 Dangerous Poor Military Dynamite Ml Quarry and rock cuts 20, 000 0. 92 Dangerous Good Straight Dynamite 40% 15,000 0.65 Good (if (commercial) 50% 18,000 0. 79 Dangerous fired with- 60% 1», 000 0.83 in 24 hrs). Land clearing, Ammonia Dynamite 40% cratering, No. 6 commercial 9,000 0. 41 (commercial) 50% quarrying, and cap, electric or 11,000 0.46 Dangerous Poor 60% general use in rear nonelectric. 12,000 0.53 areas. Gelatin Dynamite 40% 8,000 0.42 50% 9,000 0. 47 Slight Good 60% 16,000 0. 76 Table I—Continued Relative Smallest cap requi-ed for Velocity of effectiveness Intensity of Name Principal uso detonation detonation as external poisonous fumes Water resistance (ft per sec) charge (TNT-1.00) Detonating cord Spec, blasting i;ap* PETN 24, 000 1. 66 Slight Good Blasting Caps N/A Booster Charge Spec, blasting cap* TETRYL 23, 400 1. 25 Dangerous Excellent Blasting Caps N/A Composition B Bangalore Torpedo Spec, blasting 25, 500 l. :« Dangerous Excellent cap, electric or Amatol 80/20 Bangalore Torpedo nonelectric. 16, 000 1. 17 Dangerous Poor Black Powder Time blasting fuze N/A (unknown) 0. 55 Dangerous Poor •Electric or nonelectric. CHAPTER 2 MILITARY EXPLOSIVES Section I. DEMOLITION BLOCKS AND CRATERING CHARGES 7. TNT (Trinitrotoluene) a. General. Trinitrotoluene (fig. 1 j, commonly known by the abbre- viation TNT, is one of the least sensitive of military high explosives. TNT is reasonably stable in any climate, is not affected by moisture, and is one of the most durable of military explosives for underwater use. b. Packaging. TNT, which is catalogued as "explosive TNT," is 1/2 LB BLOCK THREADED OR UNTHREADED CAP WELL I LB BLOCK THREADED OLIVE DRAB CAP WELL WRAPPER Figure 1. TAT Blocks. packaged in Vb-pound blocks, 1-pound blocks, and 8-pound blocks as follows: (1) The '/¡-pound blocks are contained in an olive drab wrapper with metal ends. One end is provided with a threaded or unthreaded cap well to receive an electric or nonelectric blasting cap. The '/a-pound blocks are packed 100 in a rec- tangular wooden box. (2) The 1-pound blocks each consist of two otherwise unwrapped V^-pound blocks of TNT in an olive drab wrapper with metal ends. One end is provided with a threaded cap well to re- ceive an electric or nonelectric blasting cap. Priming adapt- ers and the standard base on firing devices fit these threads on the cap wells. Fifty 1-pound blocks are packed in a wooden box. (3) The 8-po'und block is made of cast TNT and is individually wrapped in a waterproof barrier material, properly sealed. Eight of these blocks are packed in a wooden box. c. Uses. TNT is extensively employed for general military use in forward combat areas. The V2- and 1-pound blocks are used primarily for cutting and breaching projects.