^f a^ ^ STEEL MINE TIMBERS CARNEGIE STEEL COMPANY PITTSBURGH, PA. Cornell University Library The original of tliis book is in tlie Cornell University Library. There are no known copyright restrictions in the United States on the use of the text. http://www.archive.org/details/cu31924004670232 Cornell University Library TN 289.C28 Steel mine timbers; tables and data on tti 3 1924 004 670 232 STEEL MINE TIMBERS TABLES AND DATA ON THE PROPERTIES AND USES OF SECTIONS MANUFACTURED BY CARNEGIE STEEL COMPANY PITTSBURGH, PA. Copyright, 1917, by CARNEGIE STEEL COMPANY Pittsburgh, Pa. Seventh Edition, January 1, 1917 THE Carnegie Steel Company is the pioneer in the United States in the application of steel to the underground timbering of mines. Much of the success of such timbering is due to its recommendation of suitable and practicable forms of construction. So long ago as 1894 it worked out a type of framing suitable for use in the bituminous coal fields of Western Pennsylvania. This effort bore fruit in the next ten years in sporadic installations chiefly in the anthracite region, but the real impetus to the systematic timbering of mines dates from 1907, when this Company placed on the market a series of steel sections designed with special reference to this work. The H-beam has made steel framing as simple as the wooden framing it displaced. The data and tables which follow reflect the practical experience gained from these years of observation in the design and installation of many miles of steel timbers in rooms and headings. They constitute a clear and safe guide to what is best from the standpoint of the manu- facturer and most economical to the user. Should need for further information arise, the trained engineers of the Company will be glad to co-operate with operators in the solution of mine-timbering problems. CARNEGIE STEEL COMPANY STEEL FOR SERVICE. Many as are the advantages of wood for mine timbering, the fact cannot be too strongly emphasized that it is not universally adapted to all the constructions of underground mining operations and that in many situations its use is attended by large economic waste. Some of these wastes are: 1. Waste from the use of excess material due to the common and convenient practice of framing three-piece gangway sets from the same size timbers and the impracticability of adjusting dimen- sions nicely to the stresses they have to sustain. 2. Waste due to the removal of material in the process of framing, conservatively estimated as at least 10 per cent. 3. Waste from decay caused by insect or bacterial action under the unfavorable conditions due to relatively and uniformly high temperatures and great humidity prevalent in most mines, estimated at 55 per cent, and often very rapid. 4. Waste from fire, a constant danger inseparable from the ordinary use of wood and sedulously to be avoided underground as well as above ground. The preservation of the vital parts of the mine from fire loss merits the most careful consideration. 5. Waste due to the failure to withdraw and reuse timbering from completed rooms, abandoned headings, etc. This neglect is caused in part by the relative worthlessness of wood after service but there is a further menace in poisoned air (due to decay) and in increased fire risk, both of which contribute to the expense of mine maintenance. The use of steel avoids all these elements of economic waste. It is easy to obtain, convenient to fabricate and erect and its long life under all conditions of temperature and moisture amply compensates . for the increased first cost of its installation. Wood may be convenient, but steel is the material for service. Long endurance and minimum cost of maintenance mean ultimate economies in expenditure. PROPER DESIGN OF STEEL MINE TIMBERS. The cost of a durable material may be much enhanced by im- proper methods in its preparation for final use. Details of framing should be simple and connections should be of RELATIVE COSTS OF STEEL MINE TIMBERS • • Adjustable pin and wedge connected gangway set as first used by R. V. Norris at Nanticoke, Pa., 1897 Legs made of two channels ,each con- nected by pipe separators and resting on cast iron rocker castings. Collar, a single I-beam. Load distributed to legs by pins and wedges. Extra pin holes serve to take up differences in width or height. .^L 3- Fig. 1 — Gangway Set, Style A • • Adjustable pin and wedge connected gangway set, modern form. Legs^ made of two channels, each con- nected by pipe separators and resting on steel base plates. Collar, a single I-beam. Load distributed to legs by pins and wedges. Extra pin holes serve to take up differences in width or height. hTii - -> Fig. 2 — Gangway Set, Style B Representive Gangway Sets with Double Channel Legs CARNEGIE STEEL COMPANY minimum weight so that the cost of fabrication may be the least possible consistent with good engineering practice. Above all, the kind of steel sections to be used should be chosen with a view to the character of the stresses so as to insure proper and most economical distribution of the loading. Needless expense has been incurred in many- installations by reason of the use of improper steel sections, heavy connections and base plates, and complications in the details of fabrication. Figs. 1 to 8, inclusive, show designs of more or less merit for three-piece gangway sets. Any one of these might be adequate for use under any given loading. When adjusted, however, to the same loads, the same spans and the same clear heights, their costs differ widely. A simple compari- son is sufficient to indicate how large a factor the matter of design may become and what influence it may have in the economics of mine timbering. Assume that it is desired to substitute steel for a three- piece double-track gangway set made with 24-inch round yellow pine timbers, the legs of which are 8 feet high in the clear and the collar 17 feet long between legs, and that the steel is to carry the full load of seasoned timber. The collar will then be a 20 inch, 65 pound steel beam and the legs may each be one 8 inch, 34 pound H-beam or two 7 inch li% pound channels. The cost comparison will be as per Table I, based on plain structural steel at $1.60 per hundred pounds, f. o. b. cars Pittsburgh, Pa., with usual extras for fabrication. The figures given in Table I are for a very heavy double- track gangway set. Table II shows a similar comparison for a single-track gangway set 8 feet high in the clear and 10 feet wide between legs. If framed in wood this would require 15-inch round yellow pine timbers; if framed in steel of strength equivalent to seasoned wood timbers, the collar would be a 10 inch 25 pound I-beam and the legs each either a single 5 inch 18.7 pound H-beam or two RELATIVE COSTS OF STEEL MINE TIMBERS • • • • Pin and wedge connected gangway set adjustable at the top and pivoted at the bottom. Legs made of two channels each, con- nected by pipe separators and supported on pins in steel base plates. Collar, a single I-beam. Load distributed to legs by pins and wedges. Extra pin holes serve to take up differences in width or height. ^L Fig. 3 — Gangway Set, Style D Economical gangway set made of channel legs and I-beam collar, but not adjustable. The twd channels" forming a leg are connected by bolts and pipe separators, carry angle brackets at their tops on which the collar rests and foot on a structural steel base plate. Load distributed to the legs by rivets. Bent angle lugs prevent undue lateral, motion. £^d_ -aJa Fig. 4 — Gangway Set, Style E Bepbesentive Gangway Sets with Dooble Channel Legs CARNEQIE STEEL COMPANY 6 inch 10.5 pound channels. TABLE I. COMPARATIVE COSTS OF STEEL MINE TIMBERS Double-Track Gangway Supports 17-Foot Span— 8 Feet High Figure No. WEIGHT PER SET COST PER SET COST PER POUND Style Without Base, Pounds With Base, Pounds Without Base Plates, Dollars per Set With Base Plates, Dollars per Set Without Base Plates, Cents per Pound With Base Plates, Cents per Pound A 1 1930 2500 43.57 67.25 2.26 2.69 B 2 1930 2030 43.57 46.58 2.26 2.29 D • 3 1930 2100 43.57 51.30 2.26 2.44 E 4 1670 1770 31.78 34.85 1.90 1.97 C 5 1700 1790 31.28 34.00 1.84 1.90 F 6 1680 1720 31.55 32.70 1.88 1.90 G 7 1680 1720 31.58 32.70 1.88 1.90 I 8 1720 1770 31.15 33.17 1.81 1.87 TABLE II. COMPARATIVE COSTS OF STEEL MINE TIMBERS Single-Track Gangway Supports 10-Fcot Span— 6 Feet High Figure WEIGHT PER SET COST PER SET COST PER POUND Style Without Base, Pounds With Base, Pounds Without Base Plates, Dollars per Set With Base Plates, Dollars per Set Without Base Plates, Cents per Pound With Base Plates, Cents per Pound A 1 765 945 17.48 28.47 2.29 2.80 B 2 765 810 17.48 18.95 2.29 2.34 D 3 765 800 17.48 18.65 2.29 2.33 E 4 605 660 11.50 13.20, 1.90 2.00 C 5 565 605 9.88 11.15 1.75 1.84 F 6 569 590 -10.84 11.49 1.90 1.95 G 7 566 587 10.78 11.44 1.91 1.95 I 8 600 630 11.90 13.30 1.98 2.11 The figures given in both these comparisons are for material not painted. If painted one shop coat of the usual shop mixture, the cost would be $2.00 per net ton additional throughout. The figures in both comparisons are based on plain structural steel at $1.60 per hundred RELATIVE COSTS OF STEEL MINE TIMBERS Simple three-piece gangway set. Legs made of single I-beams or H-beams which foot on plain or fabrica- ted steel base plates. Collar, a single I-beam or H-beam. Load distributed to legs by beveled castings or forgings. Lateral motion resisted only by bolts. Fig. 5 — Gangway Set, Style C Ideal form of simple and economical gangway set, the equivalent of the three-piece wooden set. Legs made of single H-beams resting on plain or fabricated base plates. Collar, a single I-beam or H-beam. Load distributed to legs by rivets and and direct bearing. Bent angle lugs prevent undue lateral motion. — njrn Fig. 6 — Gangway Set, Style F Bepbesentativb Gangway Sets with H-Beam Legs 9 CARNEQIE STEEL COMPANY pounds f. o. b. cars, Pittsburgh, Pa., taken as a fair normal price. The cost per set can be adjusted to any other basis by the simple additiofn or subtraction of the weight multi- plied by the price differential. RELATIVE COST OF STEEL AND WOOD. Variable con- ditions at mines make it difficult to compare the cost of steel and wood mine timbers except on the basis of specific instances. As a general rule, when consideration is had to depreciation and ultimate expenditure, the operator can well afford to pay for correctly designed steel sets three or four times the cost of wood sets of equivalent strength. In a few cases steel has even been substituted for wood at almost equal cost prices. Comparisons should always be based on first cost, length of service, cost of renewal and maintenance and interest on total investment. Consideration should also be had to such apparently extraneous matters as ventilation, fire risk and interruption of operations when wooden timbers come to be renewed. As a specific example based on costs only, take a lot of double-track steel gangway sets installed in 1908 in the Maxwell Colliery of the Lehigh and Wilkesbarre Coal Company, which replaced wood sets with an average life of two and one-half years. At the end of 15 years the comparison would stand as follows: 6 Wood Sets at S15.00 each erected 3 90.00 Interest compovmded at 6 per cent 63.56 Total per Unit Set S153.56 1 Steel Set at $40.00 erected S 40.00 Interest compoimded at 6 per cent 55.86 Two paintings at Sl.OO 2.00 S 97.86 Less value of scrap 12.03 Total net cost S 85.83 Saving per set on steel 67.73 Saving per set per year 4.52 10 RELATIVE COSTS OF STEEL AND WOOD TIMBERS Simple and economical gangway set identical with Style F except that bars are used to prevent lateral motion instead of angles. Legs made of single H-beams resting on plain or fabricated steel base plates. Collar, a single I-beam or H-beam Load distributed to legs by rivets and direct bearing Fig. 7— Gangway Set, Style G Flexible three-piece gangway set. Legs made of single H-beams footing on rocker castings. Collar, a single I-beam or H-beam rest- ing on rocker castings. Load distributed to legs through cast bearing surfaces of the rocker castings. Mil I ~t Fig, 8 — Gangway Set, Style I Representative Gangway Sets with H-Beam Legs CARNEQIE STEEL COMPANY Table III, reprinted in condensed form from Coal Age, Vol. 8, page 835, (1915) is rearranged from a similar table prepared for its own use by a coal company operating bituminous mines and may be taken as a rough guide to the normal expectation as to relative costs of steel and wood. It deals, however, with first and renewal costs only and does not consider the effect of accumulated interest on investment. English practice indicates that the use of steel means a reduction of two cents per ton of coal mined in England. This would likely hold good for the deeper coal mines of the United States and would indicate a saving of 30 per cent in timber cost in the anthracite region. The reduction would be somewhat less in bituminous mines but in any case worth consideration. STRESSES IN MINE TIMBERS. In the use of steel for timbering, the safe guide is experience. The exact amount and exact direction of the pressures exerted by roof, walls and floor are in many cases indeterminate. General principles only can be stated. The interpretation of these principles must rest upon experience and analogy. Where steel is to replace wood, the problem of the designer is merely to select from the tables steel sections equivalent in strength to the wooden timbers which are in use and then to work out connections and other details so as to insure minimum cost of fabrication. If experience indicates the wood timbers to be too light, if they fail from over-strain rather than decay, the steel sections should be made somewhat heavier than required by the tables so as to cover that over-strain. The strength of an assemblement is the strength of its weakest member. In a three-piece gangway set each leg seldom carries more than half the load on the collar and in most cases needs only to be proportioned thereto. Where this method of computation loads a leg to its full theoretical value, it is customary to use the next heavier section to provide against cross bending due to the wedging, _ RELATIVE COSTS OF STEEL AND WOOD TIMBERS TABLE III— RELATIVE COST OF STEEL AND WOOD BEAMS First Cost Delivered Underground at Mine Face Final Cost Computed for 20- Year Period Span, Feet Size of Beam Weight, Pounds Safe Load, Pounds First Cost, Dollars 20- Year Cost, Dollars Favorable Unfavorable Conditions Conditions STEEL BEAMS 16 10 in. 25.0 lb. I-beam 467 16,280 9.34 14.34 34.34 12 8 in. 18.0 lb. I-beam 266 12,640 5.31 9.81 28.31 8 6 in. 12.251b. I-beam 136 9,680 2.72 6.72 23.72 14 6 in. 23.8 lb. H-beam 401 11,460 8.02 12.52 31.02 12 6 in. 23.8 lb. H-beam 354 13,370 7.07 11.07 28.07 14 4 in. 13.6 lb. H-beam 231 4,070 4.62 8.87 26.62 12 4 in. 13.6 lb. H-beam 204 4,750 4.08 7.83 24.08 SQUARE SAWED WHITE OAK BEAMS 16 12 8 14 12 14 12 11 X 14 inches. 9 X 12 inches. 6 X 10 inches , 9 X 12 inches. 9 X 12 inches , 8x8 inches . 8x8 inches. 885 483 192 552 483 327 ' 286 16,470 13,200 9,170 11,310 13,200 4,470 5,210 9.24 5.04 2.00 5.76 5.04 3.40 3.00 37.72 24.12 14.00 26.28 24.12 18.20 17.00 94.68 62.28 38.00 67.32 62.28 47.80 45.00 SQUARE SAWED LONGLEAF YELLOW PINE BEAMS 16 12 8 14 12 14 12 9 X 14 inches . . 10 X 10 inches. . 8x8 inches . . 8x12 inches . . 8 x 12 Inches . . 6x8 inches . . 6 X 8 inches . . 693 15,920 7.56 428 12,040 4.68 195 9,240 2.12 469 11,890 5.12 411 13,860 4.48 235 3,960 2.56 205 4,620 2.24 32.68 23.04 14.36 24.36 22.44 15.68 14.72 82.92 59.76 38.84 62.84 58.36 41.92 39.68 RENEWAL AND MAINTENANCE CONDITIONS Steel, favorable, painted every fourth year. Steel, unfavorable, painted every year. Wood, favorable, timber renewed twice. Wood, unfavorable, timber renewed six times. Loads considered to be uniformly distributed over length of span. Sizes computed on the basis of 1,100 pounds fiber stress per square inch for white oak, 1,300 pounds for longleaf yellow pine, and 16,000 pounds for steel. 13 CARNEQIE STEEL COMPANY weight of lagging and other indeterminate factors. In new work it is safest to use somewhat heavier sections than required by the rules. Lighter sections may be put in later if found to be sufficient. The problem is to deter- mine the probable load on the roof support or collar and the character and amount of the stresses in the legs, if a three-piece or four-piece Set is to be used. Fig. 9 — Typical Rock Cleavage, Level Strata 1. Level Strata Timbering. Fig. 9 shows diagrammatic'ally method of rock cleavage over gangway supports where the strata are horizontal and the rock of uniform texture. In this case the cleavage is symmetrical and the load sustained by the collar is the fracture prismoid, the height of which will be the half span length by the tangent of the angle of adhesion of the material. The total weight sustained by MINE TIMBER COMPUTATIONS the collar will be the product of the area of the triangle of fracture by the distance between supports and by the weight per cubic unit of the rock; W= ^ . The bending moment, deflection, etc., produced in the collar may be computed by the flexure formula for beams supported at their ends and loaded with a load increasing uniformly to the center, Fig. 10; m; max:. W ' 2 ^ I W max. E (max. shear)=Ei M, distance x = Wx (M - ^) M max., distance-^ MillilOP'^^Ri D max. D Fig. 10— Flexdbe Fosmula, Stmmetbical Loadinq The load on each leg will be half the load on the collar. The notation used in the above formula and those which follow is that used in the Carnegie Pocket Companion, as follows : w ^Superimposed load, in pounds per unit of volume, etc. W =Superimposed load supported by beam, in pounds. W max=Maximum safe load at point given, in pounds. R, Ri =Reactions at points of support, in pounds. 1 ^Span length, in inches. X =Distance to any point of moments, in inches. 8 ^Distance center to center of supports or gangway sets, in inches. c =Distance to center of gravity, in inches, f ^Bending stress, extreme fiber, in pounds per square inch. E ^Modulus of elasticity, in pounds per square inch. I =Moment of inertia, in inches*. S ^Section modulus, in inches^. D ^Deflection at point given, in inches. M =Bending moment at point given, in inch pounds. M max=Maximum bending moment, in inch pounds. a, P =Angles of adhesion in cleavage triangle. 15 CARNEQIE STEEL COMPANY 2. Inclined Strata Timbering. The loads in mine timber work are rarely symmetrical and in consequence the method of computation must necessarily be modified in the light of actual conditions as to the character of the strata, method in which fracture takes place, danger from squeeze and other circumstances not reducible to exact analysis. The prime consideration is to prevent fracture beyond the lines of the necessary excavation. A soft roof can be safely held if timbered immediately upon exposure to the air. Delay means needless work. Fig. H — AcTU.^L Rock Cleav.\ge, Inclined Strata Fig. 11 shows the more common condition where strata are inclined and cleavage is not symmetrical and arch fashioned but irregular. In this case the apex of cleavage is nearer one end of the collar than the other. The magni- tude of the load is computed, as in the case of symmetrical cleavage, from the weight of the cleavage prismoid, but the effect of the bending stresses on the collar due to that load requires somewhat more intricate analysis. The MINE TIMBER COMPUTATIONS center of gravity of the load must be determined and from that basis the maximum bending moment can be computed. If the apex of the cleavage prismoid is over a support, the maximum bending moment is the same as for a beam loaded with a load increasing uniformly to one end. If the apex of the cleavage prismoid is over the center of the beam, the maximum bending moment is the same as for a beam loaded with a load increasing uniformly to the center. The values of M max. will, therefore, range within these two limits; that is, from .1287 Wl to .1667 Wl, but can be computed exactly from the formula given in Fig. 12. In so much, however, as the question of safety should always come into consideration, the exact, but more intricate, method of computation may be waived and the bending moment computed as if for a load which increases uniformly from end to center. ■^ swl (a tan a) W (3 cax - x3) ~ 3 al [* X — -^ r- M, distance X Fia. 12— PLExnHE_FoHMDLA, M max.,distanceV^— ^''^^^ Unsymmetrical Loading ^a^.,^-=^a.^^y i^a 31 The loads on the two legs are not equal and in their design the more exact solution of the problem should be made and the reaction at each end of the beam computed in accordance with the formula. 3. Size of Legs and Collar. Bending moments should be computed in, or reduced to, inch pounds. When so computed the size of section to be used may be taken from the table of elements by dividing the bending moment by the safe working stress allowed, usually taken at 16,000 pounds per square inch; the result is the section modulus of the required section. The size of section to be used may CARNEQIE STEEL COMPANY also be taken from the table by computing the section modulus of the section directly from the load and the span. The size of leg sections can be taken directly from the tables of safe loads, noting that values used must be those corresponding to the length of the leg. Allowance should be made for the effect of bending stresses in the leg due to the inclined character of the strata, which makes the result- ant line of pressure at the supports out of parallel with the legs, so that the total resistance to be sustained by the legs may be greater than the end reaction computed from the formulas. 4. Approximate Safe Loads. In the absence of complete tables of the elements of sections, the strength of wood and steel timbers may be computed by the following simple methods which are sufficiently precise for the substitution of one class of material for another: a. Rectangular Wooden Beams. Multiply the width of the beam by the square of the height and divide the result by the length in feet. The quotient multiplied by 144, 111, 122 or 100 will be the uniformly distributed load in pounds for yellow pine, spruce, white oak or white pine respectively. b. Round Wooden Beams. Divide the cube of the diameter by the length in feet. The quotient multiplied by 86, 66, 73 or 60 will be the uniformly distributed load in pounds for yellow pine, spruce, white oak or white pine respectively. c. steel Beams. Dividc the f ollowiug coustauts by the length in feet; the result will be the safe uniformly dis- tributed load in net tons: 15" 42 lb. Beam 314 8" 18 lb. Beam 76 12" 31.5 lb. Beam.. '. . . 192 7" 15 lb. Beam 55 10" 25 lb. Beam 130 6" 12.25 lb. Beam 39 < 9" 21 lb. Beam 101 5" 9.75 lb. Beam 26 d. Safe Loads on Wooden Struts. The Strength of the material used in struts, whether iron or steel, decreases as the ratio 18 MINE TIMBER COMPUTATIONS I-Beams Laid on Brick Walls, Delaware & Hudson Co., Scranton, Pa. Roof Supports, Aline Stable,. W. ,J. Rainey Co., Connellsvillc, Pa. Fig. 13 — I-Beam Roof Supports, Represe.nt.vtive Install.\tions CARNEQIE STEEL COMPANY of the length to the width (ratio of slenderness) increases, consequently a simple easily remembered formula cannot be set down. The general formula for the compressive unit stress in pounds per square inch of oak and longleaf yellow pine is 1300 (l-I/60d), spruce 1100 (l-l/60d), where 1 is the unsupported lengtji of the leg in inches and d least diameter or width in inches. e. Safe Loads on Steel Struts. H-beams are the stccl sectious best fitted for use singly in mine timbering to resist com- pressive stresses and are generally employed where the length of the member is not more than 22 times its width. In such cases the safe load in net tons may be obtained by multiplying the weight per foot of the section by 1.9. Where the length of the member exceeds this value, reference must be had to the general formulas or the tables on safe loads. ROOF SUPPORTS. The simplest use of steel in underground mine timbering is that in which single I-beams or rails are used to span a roadway. Where the coal is good, solid and not liable to crush, the supports may be laid directly on the coal with or without bearing plates made of steel, wood or stone. Places of unusual weakness may be taken care of by short wooden or steel props of longer or shorter lengths as conditions may require to obtain solid bearing. They may also be laid on rubble walls built of stone taken down within the mines or on brick work, all as shown in the illustrations. Figs. 13 and 14. Table IV shows the relative values of rail sections as compared with I-beams and indicates the superiority of the latter for mine timbering purposes : First, for equivalent strength, beams are 50% lighter. Second, for equivalent strength, beams are much deeper; consequently the deflection is much less and their use is, therefore, in the interest of greater stabiUty. Third, the wider flanges of the beams offer much better support for lagging. 20 STEEL ROOF SUPPORTS Beams Laid on Coal and Wood Props, Youghiogheny & Ohio Coal Co. Beams Laid on Coal and Short Sprags, Youghiogheny & Ohio Coal Co. Fig. 14 — I-Beam Roof Supports, Representative Installations 21 CARNEGIE STEEL COMPANY TABLE IV— RELATIVE VALUES OF STEEL RAILS AND BEAMS 1 RAILS BEAMS Depth, Weight Weight Section Depth, Inches Weight Section Difference per Yard, per Foot, Modulus, per Foot, Modulus, Pounds, Pounda Pounds Inchess Pounds InchesS per Foot 5H 100 33.33 14.55 8 18.0 14.2 15.33 5% 90 30.00 12.19 7 20.0 12.1 10.00 5 3^8 85 28.33 11.08 5 80 26.67 10.07 7 17.5 11.2 10.83 4l%6 75 25.00 9.10 7 15.0 10.4 11.67 4H 70 23.33 8.19 4'Ao 65 21.67 7.37 ■ 6 17.25 8.7 7.75 4M 60 20.00 6.62 6 14.75 8.0 8.58 4yio 55 18.33 5.75 6 12.25 7.3 9.42 SVs 50 16.67 4.98 3"/ie 45 15.00 4.25 5 14.75 5.5 3.58 3H 40 13.33 3.62 5 9.75 4.8 6.92 3%6 35 11.67 3.02 4 10.5 3.6 2.83 3M 30 10.00 2.53 2K 25 8.33 1.77 4 7.5 3.0 4.17 2J^ 20 6.67 1.43 3 5.5 1.7 2.83 At normal prices, therefore, the substitution of rails for I-beam sections is uneconomical and indeed they should be considered only on the basis of very low prices. GANGWAY SETS. As already noted, many different types of construction have been devised for three-piece gangway sets. Practical experience indicates that the Style F set combines that simplicity of arrangement, economical distribution of material and ease of fabrication and erection which makes it the preferable style for all ordinary use. Where loads exceed the limits of the H-beam, the double channel styles such as B or E may be employed, but it is extremely seldom that conditions require heavier sections than the 8 inch H-beams. The reason for this is that while the I-beam is the most economical section in resistance to cross bending stresses, the H-beam is the most economical in resistance to com- pressive stresses. The use of the two sections, therefore, combines the resistance to bending of the one with the STEEL ROOF SUPPORTS Simple and economical three-piece gangway set for very light loads. Legs made of single H-beams or I-beams. Collar, a single I-beam or H-beam. Load distributed to legs by rivets and direct bearing. This form of gangway set used to avoid difficult fabrication, instead of Style F, where loads require only small beams. 3- Fig. 15 — Gangway Set, Style K Simple and economical three-piece gangway set as used by Lehigh Coal & Navigation Company Legs made of single I-beams or H-beams. Collar, a single I-beam or H-beam. Load distributed to legs bv rivets and direct bearing. Style L differs from Style F in the arrangement of base plates. I — ^an Fig. 16 — Gangway Set, Style L Rephesentative Gangway Sets -with H-Beam Legs ^^^ 23 CARNEGIE STEEL COMPANY resistance to compression of the other. In addition the shape of the sections makes framing details simple, and, therefore, in the Style F set is contained the closest practical equivalent to the three-piece wooden set in general use previous to the introduction of steel. Where the loads are light and the leg sections quite small, there is hardly sufficient room in the leg for web connection angles. In such cases the Style F set is modified as shown in Fig. 15, Style K. The Style. F gangway set may be further modified by the use of bars to prevent lateral motion in place of the angle lugs as shown in Style G, Fig. 7. The base plates may be plain or fabricated, as shown in Figs. 18, 19 and 20, or may have upstanding angles as shown in Fig. 21, the general arrangement of which is further illustrated in Fig. 16, Style L. Modifications of this character do not affect the essential features of the Style F set and have relatively little influence on the cost. Their use is determined solely by the preference of the purchaser. When the proper sizes of leg sections and collars have been determined with a view to the loads to be sustained, the sizes of fittings are likewise approximately fixed. The standards used by this Company are as given in Table V and should be followed in the interest of economy and good engineering practice. FOUR-PIECE GANGWAY SETS. Steel is as elastic as wood. It can be cut and fitted to any requirement. It is more economical of course to have the framing done in a fabricating shop, but after all its use is accompanied by a high degree of simplicity. Quotations will be made for any conditions which may arise. Fig. 17, gangway set Style M, shows a type of framing which has come into somewhat extensive use in the mines of the Youghiogheny & Ohio Coal Company, where a Style F set is supported on a channel sill. The sill forms STEEL GANGWAY SETS Simple and economical four-piece gangway set. Legs made of single H-beams or I-beams. Collar.a single I-beam or H-beam. Load distributed to legs by rivets and direct bearing. Legs rest on and are attached to a steel channel sill which carries the track and insures firm footing on soft ground. aAc. _i-jJO Fig. 17— Pour-Piece Gangway Set, Style M Fig. 18— Plain Base Plate Any Style Legs 0.0 0.0 o o o o o "o o" o Fig. 19— Fabricated Base Plate H-Beam Legs o o o o ©"S o" o o .o o. o o"o o" o Fig. 20— Fabricated Base Plate Double Channel Legs Fig. 21 — Fabricated Base Plate H-Beam Legs Style M Gangway Set and Base Plate Details 25 CARNEQIE STEEL COMPANY TABLE V— STYLE F MINE SUPPORTS Sizes and Weights op Standard Fittings Weights Include Bolts or Rivets LEG AND COLLAR CONNECTIONS Size of Leg, Inches Number and Size of Angles Weight, Founds 2— 3H X 2}^ X ^" X 0' 4J^" 4— 3M x2>^ X J^"x 0' 3" 2— 3M x2M X H" xO' 5M" 4—3}^ x2M X 'A" xO' SVi" l—ZVi x2^x M"xO' 6" 4— 3K x2H X %" xO' 5" 2— 3K x2i^ X M"xO' 7" 4—3}^ X 3 X %" xO' 6" 20 26 31 Instead of above fittings for 4-inch legs, best practice is to use two angles 6 X 6 X H" X 0' 4", weight 22 pounds, as per Style K, Fig. 15. BASE PLATES Size of Leg, Inches Size of Plates Size of Bars or Angles Weight, Founds Plain Base Plates, Fig. 18 4 8x %" X 0' 8" 14 5 9x %" X 0' 9" ■ 18 6 10 X )4" X 0' 10" 28 8 12 X K"x 1' 0" 41 Fabricated Base Plates, Fig. 19 4 8 X M" X 0' 8" 2x K" 34 5 9 X M" X 0' 9" 2x %" 40 6 10 X M"x0' 10" 2x H" 58 8 12 X %" X V 0" 2x %". 75 Fabricated Base Plates, Fig. 20 4 6 X M" x 0' lOM" 5 X 314 X ^" xO' 3M" 40 5 8 X %" X 0' WW 5 X 3K X K" X 0' Ai4," 56 6 10 X J4"x0' lOK" 5x3>ii X M" xO' bVi" 68 8 12 X %" X 1' M" 6x6 X %e" X 0' 6" 104 STEEL FRAMED PUMP HOUSES not only a transverse tie for the legs in order to insure proper distribution of the load on a soft bottom, but also in addition carries the track, thus dispensing with separate ties. The angle connection lugs are riveted or bolted to the floor channel in the shop; the rails^are fastened to the sill by rail chps such as are used in standard mine tie construction. PUMP HOUSES AND STABLES. Next to the gangway support the first use of structural shapes in the United States within the mines seems to have been made at the pump house of the Hazelton Shaft Colliery, No. 40 Slope, Lehigh Valley Coal Company, and a number of installations bear witness to the satisfaction which arises from the use of steel in such cases. Very extensive installations of steel have also been made in the way of underground stables, mine locomotive rooms, etc. Fia. 22 — -Steel Framed Pump House Many kinds of lagging have been in use, such as wooden poles, boards, old rails, thin concrete slabs, etc. A very 27 CARNEQIE STEEL COMPANY excellent method is to use steel plates, which has English practice to commend it and which is indicated typically in Fig. 22, which shows a steel framed pump house made with Style F supports lagged with ^-inch plates. The collar is supported in the middle by a beam which carries a trolley for handling the machinery and which in turn rests on H-beam posts at center and ends. The plates are cut in short lengths for easy assemblement and held in position by 5^-inch bolts. Corrugated iron may also be employed with advantage in situations where moisture conditions do not raise any presumption of early corrosion and where for that reason increased thickness of metal might not be desirable. ^ ^1^^ Base and Cap. -Plain Prop. Base and Cap. ^Plain Prop. Base and Cap. 'Fabricated Prop. Pig. 23 — Vakiocs Types of Steel Mine Pbops STEEL PROPS. The 5-inch beam with 4-inch flange came into use for single props in England, about 1890, and is STEEL IWrNE PROPS quite common to-day in English mines, while in Germany the tendency has been along the lines of the development of collapsible forms. Such collapsible forms have not come into use in the United States more than experimental- ly, but the English use of H-beams is to be recommended for mine prop work with plank caps or thin steel plates. In the United States many props are in use made of H-beams with steel caps and bases as shown in Fig. 23. Such props embody the most practical economy in the way of fabrication and their use should be quite economical where conditions are severe. Inasmuch as the seams in any particular mine are quite uniform in height, there seems to be no real need for much adjustability. MINE SHAFTS. In present day practice, permanent mine shafts are made of reinforced concrete or steel. Fig. 24 — Elliptical Concrete Hoisting Shaft A typical installation of the former case is shown in Fig. 24. The buntons dividing the compartments and the ladder-way framing are made of steel which may likewise, as a matter of ultimate preservation, be imbedded in cement placed against the metallic surfaces with- or without the use of metal lath. The H-Beam is admirable for this use. 29 CARNEQIE STEEL COMPANY 1o\ 6"-23.8 lbs. H-Section 5' -8° Cage 5 _JS i9 Skip -13.6 Ibs.H-Section Skip " .4"-13.6 Ibs.H-Section Pipes 17' -6" Five Compartment Mine Shaft Section A-A ul L"j Fig. 25 — Typical Rectangtjlab Steel Framed Mine Shaft Fig. 25 shows a typical five-compartment mine shaft framed exclusively in steel and lagged with wooden plank, concrete slabs or corrugated iron. The shaft sets are made of H-beams and the stuttles are made of angles whose use secures stiffness while at the same time it dispenses with the hanging rods necessary in the installation of wooden sets. With this type of construction the load is distributed equally on the bearers above and below. The advantage of the H-beam wall plate over other forms of steel sections is that it provides ample bearing against the sides of the shaft, together with sufficient strength to take care of any bending stresses due to the settling of the strata, while it is also admirably adapted to 30 STEEL SHAFT SETS resist compression from the action of the shaft walls on the wall plates. Owing to the readiness with which it may be molded to form, reinforced concrete is the best material for the construction of elliptical shafts. Steel lends itself more readily to the construction of rectangular shafts and in that way is the exact substitute for wood. Carnegie Steel Company does not furnish steel mine timbering fabricated ready for use in shaft work. Quotations, however, will be made by American Bridge Company. ERECTION METHODS. Inasmuch as steel mine timbers are fabricated complete in the shop, they are ready for erection when they reach the mine face, and no further cutting or fitting is necessary. Erection, therefore, is quite simple and no other tools are needed than wrenches. The usual method of erection is to assemble the three pieces complete on the floor, bolt the connections together and raise the set into position, either by main strength or by a line thrown over the collar and attached to a snatch block fastened at some convenient point. Three-piece gangway sets Style F have been erected complete and wedged in place in eight minutes. Inasmuch as the steel sets are only about one-third as heavy as wooden sets of equivalent strength, their erection not only requires less time, but also the expenditure of a much less physical effort. Their lightness is, therefore, a distinct advantage to be considered in any estimates as to the relative cost of steel and wood. Stiffness is as important as strength and the spacing of timbering should be such as to compel the different sets to act together as a unit under any sudden stress or shock. Light sections with close spacing are, therefore, preferable to heavy sections on wide spacing. The roof itself serves as a beam to distribute the load over two or more sets, whereas on wide spacing there is much more danger of the 31 CARNEQIE STEEL COMPANY roof falling in between the sets. The closer spacing also permits the use of much lighter lagging. PRESERVATION OF STEEL MINE TIMBERS. The economi- cal use of steel within the mines requires a like degree of care for its preservation as accompanies its use above ground. At the same time conditions underground are not nearly so severe as above ground; the steel is not exposed to those alternations of high and low temperatures, dryness and wetness, strong light and darkness with which above ground construction has to do and which are especially accelerative in the deterioration of protective coatings. Early objections to the use of steel due to the presence in some mines of acid-laden waters have not stood the test of experience, which indicates that only the simplest means are necessary for the absolute guarantee of an extremely long life for steel timbering. To insure such long life and, therefore, the utmost economy in ultimate expenditure, the base plates should be set in the dry. Where they cojne on the edges of ditches, it may be desirable to set them on low concrete piers. Where the heading is permanent, the cleanliness of the mine and the general efficiency of the transportation service will justify that small additional expense which might be incurred in the use of concrete piers or foot walls throughout the heading. It is a common observation that attention to details of this kind results not only in better working conditions for the men, but actually in increased efficiency throughout the mine. All steel within the mines should be well painted arid kept painted. The pigments should be good and applied with care. Carbon paints in whose manufacture sulphuric acid has been used, and oxides of iron manufactured by chemical processes or recovered as a by-product of metallurgical processes are to be avoided. A metallic paint should be used for the first or shop coat by reason of its adhesive qualities. The second coat should be a moisture excluder. 82 MINE TIMBER PRESERVATION For the first coat, therefore, red leads, natural iron oxides or pigments with zinc base should be employed. Natural carbons, such as graphite, and hydro-carbons, such as asphalt, gilsonite and ozokerite, may be recommended for second coat work if properly ground and mixed with a good vehicle. For the best service it is recommended that the steel be painted at the shop with a mixture of red lead, oil and asbestine, in the proportions of 15 pounds of red lead and 2 pounds of asbestine to a gallon of pure raw linseed oil, with sufficient japan dryer to work well; and that a first class graphite paint be applied thoroughly as a field or second coat to protect the shop coat and to fill up any vacancies or voids therein. The theory which underlies this recommendation is the use of a practically inhibitive pigment to prevent the inception of corrosion in the steel, and the use of a second coat to protect the first from atmospheric and temperature conditions. Repainting within the mines should be done on clean surfaces absolutely free from all rust, paint skins, dirt, etc. It is not sufficient to apply a new coat of paint over an old paint surface under which traces of corrosion already appear. The new paint will cover the old surface and may adhere firmly thereto, but the corrosion goes on underneath just the same. Attention to these small details will insure a high degree of durability. WORKING STRESSES. The tables of safe loads, etc., which follow are based on stresses customary in structural work and are believed to represent approved practice in mine timber construction. So far as the use of wooden timbers is concerned, the data should be adjusted to the character of the materials actually furnished, particularly in view of the fact that the quality of structural wooden timbers shows a growing tendency towards deterioration. 33 CARNEQIE STEEL COMPANY WORKING STRESSES IN STEEL All parts of structures shall be proportioned so that the sum of the dead and live loads, together with the impact, if any, shall not cause the stresses to exceed the following amounts in pounds per square inch: Tension, net section, rolled steel 16000 Bending on extreme fibers of rolled shapes 16000 Bending on extreme fibers of pins 20000 Shear on shop rivets 12000 Shear on bolts, field rivets and pins 10000 Shear — average — on webs of rolled beams, gross section 10000 Bearing pressure on shop rivets 24000 Bearing on bolts, field rivets and pins 20000 Axial compression of gross sections of columns and struts, for ratio of - up to 120 19000—100 - r ^ r with a maximum of 13000 where Ineffective length of member in inches, r^corresponding radius of gyration of section in inches. For ratios of — up to 120, and for greater ratios up to 200, use the amounts given in the following table. For intermediate ratios, use proportional amounts. Ratio Amount Ratio Amount 60 13000 130 6500 70 12000 140 6000 80 11000 150 5500 90 10000 160 5000 100 9000 170 4500 110 8000 180 4000 120 7000 190 3500 The effective or unsupported length of m,ain compression members should not exceed 120 times the least radius of gyration. For bracing in secondary and unimportant members the effective length should not exceed 200 times the least radius of gyration. Workmanship shall be equal to the best practice in modern structural works. Thickness of material under stress should not be less than % inch. 34 ELEMENTS OF SECTIONS ELEMENTS OF STRUCTURAL SECTIONS • |2 2 |2 V.^ ^r ' — -^ 1 1 1 I Is -=* 3 C JU 2 Section Index Depth of Section Weight Foot Area ot Section Width of Flange Thidc- neas of Web Axis 1-1 Axis 2-2 I r S I r S In. Lbs. In.2 In. In. In.* In. In.a In.4 In. In.s ELEMENTS OP STRUCTURAL BEAMS B 1 24 80.0 23.32 7.000 0.500 2087.2 9.46 173.9 42.9 1.36 12.3 B 3 20 65.0 19.08 6.250 0.500 1169.5 7.83 117.0 27.9 1.21 8.9 B80 18 55.0 15.93 6.000 0.460 795.6 7.07 88.4 21.2 1.15 7.1 B 5 15 60.0 17.67 6.000 0.590 609.0 5.87 81.2 26.0 1.21 8.7 B 7 15 42.0 12.48 5.500 0.410 441.8 5.95 58.9 14.6 1.08 5.3 B 9 12 31.5 9.26 5.000 0.350 215.8 4.83 36.0 9.5 1.01 3.8 Bll 10 25.0 7.37 4.660 0.310 122.1 4.07 24.4 6.9 0.97 3.0 B13 9 21.0 6.31 4.330 0.290 84.9 3.67 18.9 5.2 0.90 2.4 B 15 8 18.0 5.33 4.000 0.270 56.9 3.27 14.2 3.8 0.84 1.9 B17 7 15.0 4.42 3.660 0.250 36.2 2.86 10.4 2.7 0.78 1.5 B19 6 12.25 3.61 3.330 0.230 21.8 2.46 7.3 1.9 0.72 1.1 B21 5 9.75 2.87 3.000 0.210 12.1 2.05 4.8 1.2 0.65 0.8 ELEMENTS OF H— BEAMS H 4 8 34.0 10.00 8.000 0.375 115.4 3.40 28.9 35.1 1.87 8.8 H 3 6 23.8 7.00 6.000 0.313 45.1 2.54 15.0 14.7 1.45 4.9 H 2 5 18.7 5.50 5.000 0.313 23.8 2.08 9.5 7.9 1.20 3.1 H 1 4 13.6 4.00 4.000 0.313 10.7 1.63 5.3 3.6 0.95 1.8 ELEMENTS OF STRUCTURAL CHANNELS C 1 15 55.0 1G.18 3.818 0.818 430.2 5.16 57.4 12.2 0.87 4.1 33.0 9.90 3.400 0.400 312.6 5.62 41.7 8.2 0.91 3.2 C 2 12 40.0 11.76 3.418 0.758 196.9 4.09 32.8 6.6 0.75 2.5 20.5 6.03 2.940 0.280 128.1 4.61 21.4 3.9 0.81 1.7 C 3 10 35.0 10.29 3.183 0.823 115.5 3.35 23.1 4.7 0.67 1.9 15.0 4.46 2.600 0.240 66.9 3.87 13.4 2.3 0.72 1.2 C 4 9 25.0 7.35' 2.815 0.615 70.7 3.10 15.7 3.0 0.64 1.4 13.25 3.89 2.430 0.230 47.3 3.49 10.5 1.8 0.67 0.97 C 5 8 21.25 6.25 2.622 0.582 47.8 2.77 11.9 2.3 0.60 1.1 11.25 3.35 2.260 0.220 32.3 3.11 8.1 1.3 0.63 0.79 C 6 7 19.75 5.81 2.513 0.633- 33.2 2.39 9.5 1.9 0.56 0.96 9.75 2.85 2.090 0.210 21.1 2.72 6.0 0.98 0.59 0.63 c 7 6 15.5 4.56 2.283 0.563 19.5 2.07 6.5 1.3 0.53 0.74 8.0 2.38 1.920 0.200 13.0 2.34 4.3 0.70 0.54 0.50 85 CARNEGIE STEEL COMPANY STEEL BEAMS Allowable Uniform Load in Thousands op Pounds Maximum bending stress, 16000 pounds per square inch ^ Depth and Weight of Sections | 1 § [S 24 In. 20 In. 18 In. 15 In. 15 In. 12 In. 10 In. 9 In. 8 In. 7 In. 6 In. 5 In. 3 « i 80 65 65 60 42 3IH 25 21 18 15 12.25 9.75 s Lbs. Lbs. Lbs. Lbs. Lbs. Lbs. Lbs. Lbs. Lbs. Lbs. Lbs. Lbs. 177.0 84.0 6>.0 62.2 43.2 45.0 27.6 21.0 4 50.3 40.3 37.9 30.3 "27:5 22.1 19.4 15.5 I2.y 10.3 0.27 5 173:2 76.7 52.1 0.41 240.0 200.0 165.0 144.4 123.7 108.3 123.0 63.9 54.8 48.0 43.4 37.2 32.6 33.6 28.8 25.2 25.3 21.7 19.0 18.4 15.8 13.8 12.9 11.1 9.7 8.6 7.4 6.4 6 157.1 134.7 117.9 104.7 89.8 78.5 0.60 7 178:2 155.9 0.81 1.06 8 231. y 9 206.1 138.6 104.8 96.2 69.8 42.6 28.9 22.4 16.9 12.3 8.6 5.7 1.34 10 185.5 168.7 124.7 113.4 94.3 85.7 86.6 78.7 62.8 57.1 38.4 34.9 26.0 23.7 20.1 18.3 15.2 13.8 11.0 10.0 7.7 7.0 5.2 1.66 \ 11 "4.7" 2.00 12 154.6 142.7 104.0 96.0 78.6 72.5 72.2 66.6 52.4 48.3 32.0 29.5 21.7 20.0 16.8 15.5 12.6 11.7 9.2 8.5 6.5 4.3 2.38 13 "6.0" 2.80 14 132.5 89.1 67.3 61.9 44.9 27.4 18.6 14.4 10.8 7.9 6.5 3.24 15 123.7 83.2 62.9 57.7 41.9 25.6 17.4 13.4 10.1 '7:4" 3.72 16 116.0 109.1 78.0 73.4 58.9 55.5 54.1 50.9 39.3 37.0 24.0 22.6 16.3 15.3 12.6 11.8 9.5 6.9 4.24 4.78 17 ■y.s)"' 18 103.1 69.3 52.4 48.1 34.9 21.3 14.5 11.2 8.4 5.36 19 97.6 65.7 49.6 45.6 33.1 20.2 13.7 *i6.6' 5.98 20 92.8 62.4 47.1 43.3 31.4 19.2 13.0 10.1 6.62 21 88.3 59.4 44.9 41.2 29.9 18.3 "12:4" 7.30 22 84.3 56.7 42.9 39.4 28.6 17.4 11.8 8.01 8.76 9.53 10.35 23 80.7 54.2 41.0 37.7 27.3 16.7 24 77.3 74.2 52.0 49.9 39.3 37.7 36.1 34.6 26.2 25.1 16.0 25 'ii'.i" 26 71.4 48.0 36.3 33.3 24.2 14.8 11.19 12.07 12.98 13.92 14.90 15.91 16.95 18.03 19.13 20.28 27 68.7 46.2 34.9 32.1 23.3 28 66.3 44.6 33.7 30.9 22.4 29 64.0 43.0 32.5 2^.9 21.7 30 61.8 59.8 41.6 40.2 31.4 30.4 28. P 20.9 ■ia.3 31 27'.S 32 58.0 39.0 29.5 27.1 19.6 33 56.2 37.8 28.6 34 54.6 36.7 27.7 35 53.0 35.6 26.9 36 51.5 34.7 25.2 21.45 22.66 23.90 25.18 26.48 37 50.1 33.7 "26.6 38 48.8 32.8 24.8 39 47.6 32.0 40 48.4 31.2 41 45.E ■36.4 1 27.82 29 20 42 43 44. S 43.1 29.7 so'eo 32.04 44 42.S 33:52 45 41.5 46 40.; i 35.02 36.56 47 39.; 38.14 48 38.' T 139.74 49 "87S 141.38 50 87.1 36 STEEL BEAMS, SAFE LOADS STEEL H-BEAMS Allowable Uniform Load in Thousands of Pounds Maximum Bending Stress, 16000 Pounds per Square Inch Sp-ia Depth and Weight of Sections Coefficients in Feet 8 Inch 34.0 Pounds 6 Inch 23.8 Pounds 5 Inch 18.7 Pounds 4 Inch 13.6 Pounds of Deflection 37.6 31.3 25.0 4 25.4 20.3 14.3 11.4 0.27 5 32.1 0.41 60.0 26.7 16.9 9.5 6 51.3 0.60 7 44.0 22.9 14.5 8.1 0.81 8 38.5 34.2 20.1 17.8 12.7 11.3 7.1 1.06 9 6.S 1.34 10 30.8 28.0 16.0 14.6 10.1 6.7 1.66 11 9.2 2.00 12 25.6 - 23.7 13.4 8.6 2.38 13 12.8 2.80 14 22.0 11.6 3.24 15 20.5 3.72 16 19.2 4.24 17 18.1 4,78 18 17.1 5.36 The' safe loads given in tables are for uniformly distributed quiescent loads, and include the weight of the beam. The loads are assumed to act in a plane coincident with the center line of the web and to produce a deflection in this plane only. For beams which are not secured against lateral deflection, the tabular safe loads should be reduced in accordance with the ratio of the unbraced length of beam and its flange width, given in the following table: Unbraced Length 10 X flange width 15 X flange width 20 X flange width 25 X flange width Allowable Safe I.,oad Full tabular load 90.6% tabular load 81.2% tabular load 71.9% tabular load Unbraced Length 30 X flange width 35 X flange width 40 X flange width Allowable Safe Load 62.5% tabular load 53.1 % tabular load 43.8% tabular load To obtain the vertical deflection in inches, in center of span, for the fuU tabular load of beam, divide the corresponding coefHcient of deflection by the depth of the beam, in inches. Loads in small flgures below dotted Unes produce deflections which exceed Vioo of the span. The small flgures above upper horizontal lines are the' safe loads for shear based upon the gross area of the web, at 10000 pounds per square inch. For beams loaded in the center of the span, use one-half the tabular safe loads and four-flfths of the corresponding coeBlcients of deflection. 37 CARNEQIE STEEL COMPANY i^ BEAM COLUMNS AND STRUTS 1- — j Safe Load in Thousands of Pounds [ Allowable Fiber Stress per square inch, 13,000 pounds for lengths of 60 radii or under, reduced for lengths over 60 A^ radii ; see page 34. !2 weignts ao not inciuae aetans. Effective Lengtli in Feet Depth and Weight of Sections H Beams I Beams Sin. 34 lbs. Bin. 23.8 lbs. 5 in. 18.7 lbs. 4 in. 13.6 lbs. 15 in. 42 lbs. 12 in. 3VA lbs. 10 in. 25 Iba. 9 in. 21 lbs. 8 in. 18 lbs. 7 in. 15 lbs. 6 in. 12M lbs. 5 in. lbs. 4 in. lbs. 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21. 22 23 24 25 26 27 28 29 30 31 130.0 130.0 130.0 130.0 130.0 130.0 130.0 130.0 91.0 91.0 91.0 91.0 91.0 91.0 71.5 71.5 71.5 71.5 71.5 .52.0 52.0 52.0 162.2 162.2 162.2 162.2 120.4 120.4 120.4 120.4 95.8 95.8 95.8 82.0 82.0 82.0 69.3 69.3 69.3 57.5 57. 5 46.9 46.9 37.3 37.3 28.7 28.5 24.0 19.5 15.2 13.0 10.8 8.5 56.8 50.0 43.2 36.4 44.5 38.5 32.5 26.5 33.3 28.0 22.7 50.7 45.7 40.6 35.6 30.5 94.4 85.3 76.2 67.1 58.0 77.8 69.4 61.0 52.6 44.2 63.2 55.6 48.0 40.4 153.9 140.1 126.2 112.3 98.5 109.9 98.9 87.9 76.9 65.9 66.0 60.5 55.0 49.5 44.0 38.5 18.8 16.1 13.5 10.8 86.7 80.9 75.1 69.3 63.5 57.7 51.9 30.3 26.9 23.5 20.1 16.7 13.3 22.9 19.9 16.8 13.8 10.8 35.0 31.2 27.4 23.6 19.8 16.0 125.8 119.4 113.0 106.6 100.2 93.8 87.3 80.9 74.5 26.7 24.2 21.7 19.2 16.6 14.1 50.2 45.7 41.1 36.5 32.0 27.4 22.9 40.0 35.8 31.5 27.3 23.1 18.9 86.0 79.0 72.1 65.2 58.2 51.3 44.4 37.4 59.9 54.4 48.9 43.4 37.9 32.4 26.9 35.8 33.0 30.3 27.5 24.8 22.0 19.3 16.5 47.6 44.7 41.8 38.9 36.0 33.1 30.2 27.3 24.4 21.5 69.0 65.8 62.6 59.4 56.2 53.0 49.8 46.6 43.4 40.2 37.0 33.7 30. E Area,iii.2 10.00 7.00 5.50 4.00 12.48 9.26 7.37 6.31 5.33 4.42 3.61 2.87 2.21 Il-l,in.4 ri-i, in. l2-2,in.* r2-2,in. 115.1 3.40 35.1 1.87 45.1 2.54 14.7 1.45 23.8 -2.08 7.9 1.20 10.7 1.63 3.6 0.95 441.8 5.95 14.6 1.08 215.8 4.83 9.6 1.01 122.1 4.07 6.9 0.97 84.9 3.67 5.2 0.90 56.9 3.27 3.8 0.84 36.2 2.86 2.7 0.78 21.8 2.46 1.9 0.72 12.1 2.05 1.2 0.65 6.0 1.64 0.77 0.59 Weight, Lbs. per Foot 34 23.8 18.7 13.6 42 31)^ 25 21 IS 15 12M 9M rVi Safe load values above upper zigzag line are for ratios of l/r not over 60, those between the zigzag lines are for ratios up to 120 l/r and those below lower zigzag line are for ratios not over 200 i/r. 38 STEEL COLUMNS, SAFE LOADS DOUBLE CHANNEL STRUTS Safe Load in Thousands OF Pounds Allowable Fiber Stress per square inch, 13000 pounds for lengths of 60 radii or under , reduced for lengths over 60 radii; see page 34. Weights do not include details. Description of Channels Unsupported Length in Feet Depth, Inches Weight per Foot, Pounds Double Web Thickness, Inches 8 and under 10 12 u 16 18 20 8.00 0.400 61.9 61.9 61.1 56.3 51.4 46.5 41.6 6 10.50 0.636 80.3 80.3 77.2 70.4 63.7 57.0 50.3 13.00 0.880 99.3 99.3 93.5 84.9 76.3 67.7 59.1 15.50 9.75 1.126 0.420 118.6 74.1 118.6 74.1 109.8 99.3 73.1 88.7 68.1 78.1 63.0 67.5 58.0 74.1 12.25 0.636 93.6 93.6 93.6 90.1 83.4 76.8 70.1 7 14.75 0.846 112.8 112.8 112.8 106.6 98.3 89.9 81.6 17.25 19.75 11.25 1.056 1.266 0.440 131.8 151.1 87.1 131.8 151.1 87.1 131.8 122.8 139.1 112.9 127.4 85.9 102.9 115.8 80.8 92.9 104.1 75.6 150.8 87.1 87.1 13.75 0.614 105.0 105.0 105.0 1,05.0 101.5 95.0 88.4 8 16.25 0.798 124.3 124.3 124.3 124.3 118.1 110.2 102.3 18.75 21.25 13.25 0.980 1.164 0.460 143.3 162.5 101.1 143.3 162.5 101.1 143.3 162.5 101.1 143.3 134.3 150.9 125.0 140.0 99.7 115.6 129.2 94.3 161.7 101.1 101.1 15.00 0.576 114.7 114.7 114.7 114.7 114.7 111.5 105.3 9 20.00 25.00 15.00 0.904 1.230 0.480 152.9 191.1 116.0 152.9 191.1 116.0 152.9 191.1 116.0 152.9 191.1 116.0 152.9 144.3 176.9 135.5 165.5 114.2 188.3 116.0 116.0 10 20.00 25.00 0.764 1.058 152.9 191.1 152.9 191.1 152.9 191.1 152.9 191.1 152.9 191.1 152.9 146.3 179.1 189.1 30.00 1.352 229.3 229.3 229.3 229.3 229.3 223.8 211.4 35.00 20.50 1.646 0.560 267.5 156.8 267.5 156.8 267.5 156.8 267.5 156.8 267.5 156.8 258.3 243.6 156.8 156.8 25.00 0.780 191.1 191.1 191.1 191.1 191.1 191.1 191.1 12 30.00 1.026 229.3 229.3 229.3 229.3 229.3 229.3 229.3 35.00 1.272 267.5 267.5 267.5 267.5 267.5 267.5 267.5 40.00 1.516 305.8 305.8 305.8 305.8 305.8 305.8 305.8 33.00 0.800 257.4 257.4 257.4 257.4 257.4 257.4 257.4 35.00 0.852 267.5 267.5 267.5 267.5 267.5 267.5 267.5 40.00 1.048 305.8 305.8 305.8 305.8 305.8 305.8 305.8 15 45.00 1.244 344.2 344.2 344.2 344.2 344.2 344.2 344.2 50.00 1.440 382.5 382.5 382.5 382.5 382.5 382.5 382.5 55.00 1.636 420.7 420.7 420.7 420.7 420.7 420.7 420.7 Safel line for ra oad values tios betwee to left of zigzag line s a 60 l/r and 120 I/r. ire for rat i03 of l/r not over 60; those to right of zigzag 39 CARNEQIE STEEL COMPANY TABLES FOR PINS AND WEB BEARING Two Pins Requibed por Each Strut Distance Between Channels=Flangc Width ot Beam in Inches i ^^ 1 jy. j 5 5H 6 6H 7 7}^ 8 £^. ■o -o T3 T3 TJ ■0 'V T3 TS i is t II i ■I II ■i li i II m ■i u ■I •SS' ■3 ^i "o s,t •3 s. i .2 1 •s •s ■S ^ ■s •s ■si ■3 ° i ►^ eg 11 cj %l .a "§ 9 es R cS d ■§1 ^ XI § .s II .a H a a 3 03 p 5 oa a oa s o-l S o:l a p H E-1 F H H E^ 6-1 f-' 10000 m .222 IVz .222 VA .222 VA .200 IK .200 IK .200 IK .200 m .182 VA .182 20000 IVa .364 m .364 m .333 VA ,333 m .308 m .308 m .308 VA .308 VA .286 30000 m .462 m .462 m .462 VA .429 IVi .429 VA .400 VA .400 VA .400 2 .375 40000 m .571 IH .571 VA .533 VA .533 2 .500 2 .500 2% .471 2A .471 2A .471 50000 m .667 m .667 2 .625 2 .625 2A .588 2% .588 2K .556 2% .556 2% .526 60000 2 .750 2 .750 2H .706 m ,667 2H .667 2% .632 2M .632 2% .632 2yi .600 70000 2Ks .824 iVs .824 2)i .778 m .778 2% .737 2% .737 2K2 .700 2Ji .700 2% .667 80000 2^ .941 m .888 2J^ .842 m .842 2i4 .800 2K .800 2^ .762 2¥i .762 2% .727 90000 2V4. 1.000 m .947 m .947 2}4 .900 2ys .857 2% .857 2M .818 2% .818 2% .783 100000 2Vs 1.053 m 1.053 VA 1.000 m .953 2% .953 2% .909 2Ji .870 2% .870 3 .833 110000 m 1.168 i¥i 1.100 VA 1.048 m 1.048 2% 1.000 2Vb .957 2J^ .957 3 .917 3 .917 120000 m 1.200 2% 1.143 VA 1.143 2% 1.091 2% 1.044 2A 1.044 3 1.000 3 1.000 VA .960 130000 iVi. 1.300 VA 1.238 m 1.182 2A 1.131 2A 1.131 3 1.083 VA 1.040 3H 1.040 3K 1.000 140000 2% 1.333 2H 1.273 m 1.218 2% 1.218 3 1.167 3K 1.120 VA 1.120 3K 1.077 3K 1.077 150000 i% 1.429 i% 1.364 VA 1.305 3 1.250 3 1.250 SVs 1.200 VA 1.154 3K 1.154 VA 1.111 160000 m 1.456 2Vs 1.392 3 1.333 3 1.333 iA 1.281 VA 1.231 VA 1.231 Wi 1.185 VA 1.143 170000 i% 1.546 VA 1.478 3 1.418 3H 1.362 3Ji 1.308 314 1.308 3M 1.259 3^8 1.259 ZV2 1.215 180000 VA 1.565 3 1.500 3 1.500 3H 1.440 m 1.385 3M 1.333 yA 1.333 3H 1.286 3M 1.242 190000 m 1.652 3 1.585 3H 1.520 3M 1.462 3Vs 1.408 iVs 1.408 VA 1.357 3H 1.310 zy> 1.310 200000 3 1.667 3 1.667 VA 1.600 « 1.539 m 1.482 VA 1.429 VA 1.429 i% 1.380 m 1.333 The table shows theoretical pin sizes. Diameters of actual pins should vary by quarter-inch variations only. EXAMPLE OF A PIN BEARING GANGWAY SUPPORT. Reguired the proper size beam, channels and pins for a steel gangway set with 17-foot coUar and 8-foot legs to support a superimposed load of 70,000 pounds. Table of safe loads, page 36, shows the nearest section for given load and span to be a 20 inch 65 pound beam. The load on a leg is 35,000 poimds and the flange width of the collar is 6 K inches Diameter of the two pins required for the given load and distance, by above table, is 2 inches; double web thickness, .500 inch. By table of channel struts, page 39, the nearest channel strut for the given load, height and web thickness is one composed of two 6 mch 10.5 pound channels with a capacity of 80,300 pounds and a double web thickness of 636^nch. Two 6 inch 8 pound channels, double web tWckness .400 inch, would be sufficient if the diameter of pin were increased to 2 M inches, but no material should be used in important work less than M mch tmcK. '' 40 WEIGHTS OF STEEL ANGLES WEIGHTS OF ANGLES Pounds pee Lineal Foot Thickness in Inches Size, Inches %0 M %o 'A %» 14 %o Vs 1^6 H 8 x8 26.4 29.6 32.7 35.8 38.9 *8 x6 20.2 23.0 25.7 28.5 31.2 33.8 *8 x3}4 16.5 18.7 21.0 23.2 25.3 27.5 *7 x3K 13.0 15.0 17.0 19.1 21.0 23.0 24.9 6 x6 14.9 17.2 19.6 21.9 24.2 26.5 28.7 6 x4 12.3 14.3 16.2 18.1 20.0 21.8 23.6 6 X3H 9.8 11.7 13.5 15.3 17 1 18.9 20.6 22.4 *5 x5 12.3 14.3 16.2 18.1 20.0 21.8 23.6 *5 x4 9.3 11.0 12.8 14.5 16.2 17.8 19.5 21.1 5 x3H 8.7 10.4 12.0 13.6 15.2 16.8 18.3 19.8 5 X3 8.2 9.8 11.3 12.8 14.3 15.7 17.1 18.5 *4Kx3 7.7 9.] 10.6 11.9 13.3 14.7 16.0 17.3 4 x4 6.6 8.2 9.8 11.3 12.8 14.3 15.7 17.1 18.5 *4 x3}^ 7.7 9.1 10.6 11.9 13.3 14.7 16.0 17.3 4 x3 5.8 7.2 8.5 9.8 11.1 12.4 13.6 14.8 16.0 3Kx3K 5.8 7.2 8.5 9.8 11.1 12.4 13.6 14.8 16.0 3}^x3 5.4 6.6 7.9 9.1 10.2 11.4 12.5 13.6 14.7 334 x2M 4.9 6.1 7.2 8.3 9.4 10.4 11.5 12.5 3 x3 3.71 4.9 6.1 7.2 8.3 9.4 10.4 11.5 3 x2i4 3.39 4.5 5.6 6.6 7.6 8.5 9.5 *3 x2 3.07 4.1 5.0 5.9 6.8 7.7 2^x2J^ 3.07 4.1 5.0 5.9 6.8 7.7 2}^ x2 2.75 3.62 4.5 5.3 6.1 6.8 2 x2 2.44 3.19 3.92 4.7 5.3 2 xlj^ 2.12 2.77 3.39 3.99 IMxlM 2.12 2.77 3.39 3.99 4.6 IMxlJi 1.80 2.34 IJ^xl}^ 1.80 2.34 2.86 3.35 iJ^xlM 1.64 .2.13 2.59 iMxlM 1.48 1.92 2.33 1 xl 1.16 1.49 Sections marked * are special and should not be used on work materials for which are required promptly. 41 CARNEQIE STEEL COMPANY BOLTS WITH SQUARE HEADS AND NUTS AMERICAN BRIDGE COMPANY STANDARD Weight in Pounds per 100 Bolts Length Under Diameter of Boll , Inches Head, Inches H ■Ho Ys %o 'A H 'A K 1 1 4 7 11 15 22 37 56 ik- 4 7 11 16 23 39 59 I'A 5 8 12 17 24 41 62 IH 5 8 13 18 26 43 64 2 5 9 14 19 27 45 67 101 144 2K 6 9 15 20 28 47 71 104 150 2H 6 10 15 21 30 49 74 109 155 2H 6 10 16 22 31 51 77 113 161 3 7 11 17 24 33 54 80 117 167 3K 7 12 18 25 35 58 86 126 178 4 8 13 20 28 38 62 92 134 189 4M 9 14 21 30 41 66 98 142 198 5 10 15 23 32 43 71 104 ISl 209 SM 10 16 25 34 46 75 111 159 220 6 11 17 26 36 49 79 117 168 232 e'A 28 38 52 84 123 176 243 7 29 40 55 88 129 185 254 7y2 31 42 57 92 136 193 265 8 32 45 60 97 142 202 276 9 34 49 65 105 154 218 298 10 53 71 114 167 235 320 12 61 82 131 192 269 364 14 93 148 217 303 409 Per Inch Additional 1.4 2.2 3.1 4.3 5.6 8.7 12.5 17.0 22.3 SQUARE NUTS AND BOLT HEADS AMERICAN BRIDGE COMPANY STANDARD Weights in Pounds for One Head and One Nut Diameter of Bolt, Inches IJ^ IH IM 2 2^ 3 Square Head and Nut "Weight of Shank per Inch. . 2.05 .3477 3.51 .5007 5.48 .6815 8.08 .8900 15.5 1.391 26.2 2.003 42 UNIT WORKING STRESSES FOR STRUCTURAL TIMBER WORKING STRESSES IN WOOD The strength of structural wooden timbers depends upon a number of factors; the kind of wood, the age of the tree, the time of year in which it was felled, the method of sawing, the character of seasoning, its moisture content, its proportion of heartwood to sapwood and of knots to clear wood, etc. The most recent studies in this direction have been made by the American Railway Engineering Association and the tables which follow are based on the working unit stresses adopted by that Association for railway bridges. The values are based on carefully selected timbers purchased under the standard specifications of the Association and subject to careful inspection. Where such timbers are used in building work, the unit stresses may be increased 50 per cent, but the commercial timbers which are in common use in mine work will not meet these specifications and, therefore, the unit stresses should be somewhat lower, though some increase may be allowed on work above ground executed with commercial grades of timber purchased in the open market and well seasoned. In inside mine work where the timbers are often green and, in the case of round timbers, unpeeled, and all subject to stress under rather humid conditions, the tabular values are applicable. No greater values should be used where steel is to be substituted for wooden timbers already in place. WOODEN COLUMNS AND STRUTS Unit Working Stresses in Pounds pbb Square Inch 1 d Jiongleaf WhiteOak Douglas Fir, Western Hemlock Shortleaf Piae, Spruce, Bald Cypress White Pine, Tamarack Red Cedar, Redwood Norway Pine 1300(1— l/dfiO) 1200(1— I/d60) 1100(1— l/d60) 1000(l-l/d60) 900(1— l/d60) 800(l-l/d60) 15 975 900 825 750 675 600 16 953 880 807 733 660 587 17 931 860 788 717 645 573 18 910 840 7V0 700 630 560 19 888 820 752 683 615 547 20 867 800 733 667 600 533 21 845 780 715 650 585 520 22 823 760 697 633 570 507 23 802 740 678 617 555 493 24 780 720 660 600 540 480 25 758 700 642 583 525 467 26 737 680 62'3 567 510 553 27 715 660 605 550 495 440 28 693 640 587 533 480 427 29 672 620 568 517 465 413 30 650 600 550 500 450 400 43 CARNEQIE STEEL COMPANY WORKING UNIT STRESSES FOR STRUCTURAL TIMBER ADOPTED BY THE AMBItlOAN BAILWAY ENGINEERING ASSOCIATION The working unit stresses given in the table are intended for railroad bridges and trestles. For highway bridges and trdstles, the unit stresses may be increased 25 per cent. For buildings and similar structures, in which the timber is protected from the weather and practically free from impact, the unit stresses may be increased 50 per cent. To compute the deflection of a beam under long continued loading instead of that when the load is first applied, only 50 per cent, of the corresponding modulus of elasticity given in the table is to be employed. 1 1 1 .S CO 1 1 ■» St 1 p p X SI JSAO gfggfggggggg tttttTtttttt oooooSoooooo (MCQrHOrHOoCTOlrHolCO Unit atreases are for green timber and are to be used without increasing the live load streaaea for impact. Values noted* are for partially air dry timbers. In the formulas given for columns, l==length of column, in inches, and d=least aide or diameter, in inohea. p X 51 japnn qiSnaq 0»OiOOU300 0"iOiOiOiO 01>INiO(MOiOOt^l> 0)C)ooi>oocot>aiOoocooi SM-3 ssans aniJiJO^ oooooooooooo oooooooooooo (MCOiHO'HOOONOJWOlCO aieraHifl aS«j3Ay * * oooooooooooo oooooooooooo OOOTfiOtNiDINiOWOSWiO ?3COCOCOeO(NCOCOCCCO(N« fll S83J}g OOOOOOOOOOOO CO(NrHWrHTH(Mt>OOO '-' ^ rH iH rH -1 r-I rH opmi^ifl sS^aSAy srajjg SnpiJOAl oooooooooo o t--ooi>ou:>eoi>cDM(N r^ ,_(iHi-!t-IiHiHi-HW iH W ooo^ooooooo o o)cq^oooit-«oo ;* 1 g n Modulus of Elasticity oSBjaAy rHf-iCOCO'-HOJWMOiOOiO Extreme Fiber Stress BS3J)g 3m3]JOjVl OOOO'OOOOOOOO OOOOOOOOOOOO (NC0rHCT)OC001^CTiO«'-l 93^J3Ay OOOOOOOOOOOO oooooooooooo iH-u:)COTts above horizontal lines are the maximum allowable safe loads. 51 CARNEQIE STEEL COMPANY SQUARE TIMBER POSTS SHORTLEAF PINE— SPRUCE Allowable Load in Thousands of Pounds Maximum Compressive Stress, 825 Pounds per Square Inch Length, Feet Side of Square, Inches i 6 8 • 10 12 14 16 18 20 5 13.2 13.2 6 12.3 7 8 11.4 10.6 29.7 29.0 9 10 9.7 8.8 27.7 26.4 G2.8 52.8 11 7.9 25.1 51.0 12 13 7.0 23.8 22.4 49.3 47.5 82.5 81.4 14 15 21.1 19.8 45.8 44.0 79.2 77.0 118.8 118.8 16 18.5 42.2 74.8 116.2 17 18 40.5 38.7 72.6 70.4 113.5 110.9 161.7 160.2 19 20 37.0 35.2 .68.2 66.0 108.2 105.6 157.1 154.0 211.2 211.2 22 24 26 61.6 57.2 100.3 95.0 89.8 147.8 141.7 135.5 204.2 197.1 190.1 267.3 330.0 261.3 253.4 325.6 28 84.5 129.4 183.0 245.5 316.8 30 79.2 123.2 176.0 237.6 308.0 Loads ia 3 mall figures above horizontal lines are the maximum allowable safe loads. 52 WOODEN POSTS, SAFE LOADS ROUND TIMBER POSTS OAK— LONGLEAF PINE Allowable Load in Thousands of Pounds Maximum Compressive Stress, 975 Pounds per Square Inch Length, Diameter, Inches Feet 4 6 8 10 12 14 160.1 16 13 20 12.S 27.6 49.0 76.6 110.8 196.0 248.1 5 6 7 12.3 11.4 10.6 9.8 9.0 8.2 7.3 6.5 S 9 27.0 25.7 24.5 23.3 22.1 20.8 19.6 18.4 17.2 10 11 12 49.0 47.4 45.7 44.1 42.5 40.8 39.2 37.6 35.9 34.3 32.7 13 14 75.6 73.5 71.5 69.4 67.4 65.3 63.3 61.3 57.2 53.1 15 16 17 110.3 107.8 105.4 102.9 100.5 98.0 93.1 88.2 83.3 78.4 73.5 18 19 148.7 145.8 142.9 137.2 131.5 125.8 120.1 114.4 20 22 196.0 189.5 183.0 176.4 169.9 163.4 24 242.6 235.2 227.9 220.5 306.8 26 28 30 302.2 294.1 285.9 Loads in small figures above horizontal lines are the maximum allowable safe loads. 53 CARNEGIE STEEL COMPANY ROUND TIMBER POSTS SHORTLEAF PINE— SPRUCE Allowable Load in Thousands op Pounds Maximum Compressive Stress, 825 Pounds per Square Inch V Length, Feet Diameter, Incliea 4 6 8 •10 12 14 16 18 20 5 10.4 10 4 6 9.7 7 8 9.0 8.3 23.3 22.8 9 10 7.6 6.9 21.8 20.7 41.5 41.5 11 6.2 19.7 40.1 12 13 5.5 18.7 17.6 38.7 37.3 64.8 63.9 14 15 16.6 15.6 35.9 34.6 62.2 60.5 93.S 93.3 16 14.5 33.2 58.7 91.2 17 18 31.8 30.4 57.0 55.3 89.2 87.1 127.0 125.8 19 20 29.0 27.6 53.6 51.8 85.0 82.9 123.4 121.0 16B.9 165.9 22 24 26 48.4 44.9 78.8 74.6 70.5 116.1 111.3 106.4 160.3 1.54.8 149.3 209.9 269.2 205.3 199.0 255.7 28 66.4 101.6 143.8 192.8 248.8 30 62.2 96.8 138.2 186.6 241.9 Loads in s mall figures above horizontal lines are the maximum allowable safe loads. WEIGHTS OF MATERIALS WEIGHTS AND ANGLES OF REPOSE Various Kinds op Loose and Dry Materials Kind of Material Size of Material Riitio of Slope Angle of Repose . Weight per Cu. Ft., Pounds Ashes, dry 1 on 1 45° 40 Cinders, bituminous, dry. , . . 1 on 1 45° 45 Clay, in -lumps, dry 1 on li/a 36° 52' 63 18° 26' 110 Clay and gravel, dry. ...:... 1 on IVa 36° 52' 100 Clay, gravelandsand.dry . . . .' 1 on lys 36° 52' 100 Coal, anthracite 1 on 1 1 on 1 1 on 1 1 on 1% 45° 45° 45° 36° 52' 97 84 Coal, coke 75 Coal, anthracite, in pile, loose 53 Coal, bituminous, in pile, loose 1 on IVa 36° 52' 47 Coal, coke, in pile, loose 1 on ll/g 36° 52' 28 Earth, perfectly dry, loose. . . . 1 on 1% 36° 52' 76 Earth, perfectly dry, packed . 1 on IVs 38° 52' 95 Earth, slightly moist, loose. . 1 on iVs 36° 52' 78 Earth, more moist.packed. . . . 1 on 1 45° 96 Earth, soft flowing mud 1 on 3 18° 26' 108 Earth, soft mud, packed 1 on 3 18° 26' 115 Gravel, dry 1" and less 1 on li/a 36° 52' 104 Gravel, dry Up to 2J^" 1 on lya 1 on 1 36° 52' 96 Limestone fragments, dry . . . 1" and less 45° 85 limestone fragments, dry . . . Up to 21^" 1 onl 45° 80 Sand, clean and dry 1 on 1}-^ 33° 41' 90 Sand, river, dry 1 on I}^ 1 on 1 33° 41' 45° 106 Sandstone fragments 90 1 on IVs 36° 52' 105 BEVELS Rise in Inches on Twelve Inches Bise, Inches Angle Sine Cos. Tan. Cotah. Sec. CoBec. M 1° 11' 37" .0208 .9998 .0208 48.0000 1.0002 48.0077 y2 2° 23' 8" .0416 .9991 .0417 24.0000 1.0009 24.0249 M 3° 34' 35" .0624 .9981 .0625 16.0000 1.0020 16.0308 1 4° 45' 49" .0830 .9965 .0833 12.0000 1.0035 12.0423 iji 5° 56' 49" .1036 .9946 .1042 9.6020 1.0054 9.6525 t}i 7° 7' 30" .1240 .9923 .1250 8.0000 1.0078 8.0645 IM 8° 17' 50" .1443 .9895 .1458 6.8548 1.0106 6.9993 2 9° 27' 44" .1644 .9864 .1667 6.0000 1.0138 6.0827 2H 10° 37' 11" .1843 .9829 .1875 5.3333 1.0174 5.4265 2)4 11° 46' 6" .2039 .9790 .2083 4.8009 1.0215 4.9043 2% 12° 54' 27" .2234 .9747 .2292 4.3630 1.0259 4.4768 3 14° 2' 10" .2425 .9702 .2500 4.0000 1.0308 4.1237 CARNEGIE STEEL COMPANY DECIMAL OF AN INCH AND OP A FOOT Fractions of Inch or Foot Fractions of Inch or Foot 11^ Fractions of Inch or Foot ill IP Fractions of Inch or Foot 11^ .0052 .0104 .2552 .2604 3A 3% .5052 .5104 t% .7552 .7604 1% b\ .015625 .0208 .0260 1 H .265625 .2708 .2760 3A 3M 3A m .515625 .5208 .5260 6A 11 '81 • .765625 .7708 .7760 9A It us .03125 .0365 .0417 ^ .28125 .2865 .2917 3K 3A 3M a .53125 .5365 .5417 6M 6A 6^ M .78125 .7865 .7917 9M & .046875 .0521 .0573 K .296875 .3021 .3073 3A 3H 3H iri' .546875 .5521 .5573 69 a .796875 .8021 .8073 9A 9^ 9fJ .0625 .0677 .0729 k A .3125 .3177 .3229 3M 3H 3Ji 1% .5625 .5677 .5729 6H 6U a .8125 .8177 .8229 9M 9H A .078125 .0833 .0885 1^ lA l\ .328125 .3333 .3385 3ii 4 4A il .578125 .5833 .5885 7A n .828125 .8333 .8385 9H 10 lOA A .09375 .0990 .1042 IM lA \\ .34375 .3490 .3542 i JS .59375 .5990 .6042 TVs 7* u .84375 .8490 .8542 10 K lOA 10 J€ j'l .109375 .1146 .1198 lA i\ .359375 .3646 .3698 II a .609375 .6146 .6198 7A a .859375 .8646 .8698 lOA 10 Ji lOA LK .1250 .1302 .1354 \y^ lA 1^ M .3750 .3802 .3854 M .6250 .6302 .6354 7,^ % .8750 .8802 .8854 10 J^ 10 H #1 .140625 .1458 .1510 ill sS .390625 .3958 .4010 4H H .640625 .6458 .6510 ii u .890625 .8958 .9010 10 H 10 M lOH ^5 .15625 .1615 .1667 IK H .40625 .4115 .4167 5 3.; .65625 .6615 .6667 i» !l .90625 .9115 .9167 10 K lOH U .171875 .1771 .1823 2A IJ .421875 .4271 .4323 5A 5M 5A -13 .671875 .6771 .6823 8A 1^ SI .921875 .9271 .9323 lift lift ^ .1875 .1927 .1979 11 2% A .4375 .4427 .4479 5H 1% ij .6875 .6927 .6979 1^ H .9375 .9427 .9479 llJi lift i .203125 .2083 .2135 1^ 2A II .453125 .4583 .4635 5A 5M 5A th .703125 .7083 .7135 8A Si .953125 .9583 .9635 lis iiA ,\ .21875 .2240 .2292 2^ 2fi 2M JS .46875 .4740 .4792 5H 5H 6?i u .71875 .7240 .7292 8^A 8tt 8M 3i .96875 .9740 .9792 115^ iiH llM H .234375 .2396 .2448 2ii 2^ 2ii Vl .484375 .4896 .4948 5H 5K 5H u .734375 .7396 .7448 8H 8?-g SI .984375 .9896 .9948 nil iiK llji H .2500 3 M .5000 6 M .7500 9 1 1.0000 12 56 REPRESENTATIVE QANQWAY SETS ^^S-ewW Graham-Skibo ^I'me. W. G. Duncan Coal Co., Graham, Ky. W. J. Rainey P^oyal Works Mine, Uniontown, Pa. Representative G.^ngway Sets— I 57 CARNEGIE STEEL COMPANY Mosliannon Coal Mining Co., Osceola, Pa. Curved Track, Tunnel 8, Susquehanna Coal Co., Nanticoke, Pa. Represent.\tive Gangway Sets— II 58 REPRESENTATIVE QANQWAY SETS Heavy Wooden Timbering, Anthracite Mine Heavy Steel Timbering, Anthracite Mine Representative Gangway 8ets-III CARNEQIE STEEL COMPANY Maxwell Colliery 20, Lehigh A Wilkea-Barre Coal Co., Ashton, Pa. Honeybrook GoUiery.5, Lehigh A- Wilkes-Barre Coal Co., Audenried, I'n. Represent.\tive Gangw.w Sets-TV ® Z Seam I I \ 5fee/ Gandyvay J I I ' ^7g/? of ^>-X -* ^-^ Carr, This form may be used on inquiries for Steel Mine Timbi to any district office of tlie Carnegie Steel Company. CARNEGIE STEEL COMPANY GENERAL OFFICES: Pittsburgh, Carnegie Ruikling. DISTRICT OFFICES: Birmingham, Brown-Marx Building, ;, Boston, 120 Franklin Street, BufFalo, Marine National Bank Building, Chicago, 208 South La Salle Street, Cincinnati, Union Trust Building, Cleveland. Rockefeller Building, Denver, First National Bank Budding, Detroit, Ford Building, New Orleans, Maison Blanche, New York, Hudson Terminal, 30 Church Street, Philadelphia, Widener Building. Pittsburgh, Carnegie liuilding, St. Louis, Third National Bank Building, St. Paul, riiineer Building. EXPORT REPRESENTATIVES: UNITED STATES STKEL PRODUCTS CO., New York, Hudson Terminal, 30 Church Street. PACIFIC COAST REPRESENTATIVES: UNITED STATES STEEL PRODUCTS CO., PACIFIC COAST DEPT. Los Angeles, Jackson Street and Central Avenue, Portland, Selling Building, San Francisco, Rialto Building, Seattle, 4th Avenue South and Connecticut Avenue.