Safe Building | Louis De Coppet Berg
A treatise giving in the simplest forms possible the practical and theoretical rules and formulæ used in the construction of buildings
| Title | Safe Building |
| Author | Louis De Coppet Berg |
| Publisher | Ticknor And Company |
| Year | 1890 |
| Copyright | 1889, Ticknor And Company |
| Amazon | Code Check: An Illustrated Guide to Building a Safe House |
By Louis De Coppet Berg, F.A.I.A Associate American Society Of Civil Engineers
Volume One and Two
Second Edition, Revised
To My Friend And Partner, J. Cleveland Cady, M. A., F. A. I. A., This Book Is Affectionately Dedicated By The Writer.
Introductory Remarks- IN the articles on this subject the writer proposes to furnish to any earnest student the opportunity to acquire, so far as books will teach, the knowledge necessary to erect safely any building. Whil...
- Chapter I. Strength Of Materials
- (German, Festigkeit; French, Resistance des materiaux.) All solid bodies or materials are made up of an infinite number of atoms, fibres or molecules. These adhere to each other and resist separation...
- Stresses
- The resistance to Compression, or crushing-stress, The resistance to Tension, or pulling-stress, The resistance to Shearing, or sliding-stress, and The resistance to Transverse strains, or cross-br...
- Centre Of Gravity
- (German, Schwerpunkt; French, Centre de gravite.) The centre of gravity of a figure, or body, is that point upon which the figure, or body, will balance itself in whatever position the figure or body ...
- Neutral Axis
- (German, Neutrale Achse; French, Axe neutre.) The neutral axis of a body, or figure, is an imagin- Neutral Axis. ary line upon which the body, or figure, will always balance, provided the body, or fig...
- Moment Of Inertia
- (German, Trdgheitsmoment; French, Moment d'enerlie, or Moment de giration.) The moment of inertia, sometimes called the moment of gyration, is the formula representing the inactivity (or state of res...
- The Centre Of Gyration And Radius Of Gyration
- (German, Trdgheitsmittelpunkt; French Centre de giration.) The centre of gyration is that point at which, if the whole mass of a body rotating around an axis or point of suspension were collected, a...
- The Moment Of Resistance
- (German, Widerstandsmoment; French, Moment de resistance). The moment of resistance of any fibre of a body, revolving around an axis, is equal to the moment of inertia of the whole body, divided by t...
- Modulus Of Elasticity
- (German, Elasticitats modulus, French, Module d'elasticite). The modulus of elasticity of a given material is the force required to elongate a piece of the material (whose area of cross-section is equ...
- Modulus Of Rupture
- (German Bruchcoefficient; French, Module de rupture.) It has been found by actual tests that though the different fibres of materials under transverse strains are either in compression or tension, th...
- To Find The Moment Of Inertia Of Any Cross-Section
- Divide the cross-section into simple parts, and find the moment of inertia of each simple part around its own neutral axis (parallel to main neutral axis); then, if we call the moment of inertia of th...
- Table I. Distance Of Extreme Fibres, Moments Of Inertia And Resistance, Square Of Radius Of Gyration, And Areas Of Different Shapes Of Cross-Sections
- Number and Form of Section. Distance of Neutral axis M.....N from extreme fibres. Moment of Inertia i. Moment of Resistance, r Area. a. Square of Radius of Gyration. &#...
- Calculation Of Strains And Stresses
- As we have already noticed, the stress should exceed the strain as many times as the adopted factor-of-safety, or: Streess/Strain = factor-of-safety. Or, stress = strain x factor-of-safety. This hol...
- Compression
- In pieces under compression the load is directly applied to the material. In short pieces, therefore, which cannot give sideways, the strain will just equal the load, or we have: s = w. Where s = the...
- Table II. Value Of N In Formula For Compression
- Material of pillar. Both ends of pillar smooth (turned or planed.) One end smooth (turned or planed) other end a pin end. Both ends pin ends. Cast-iron 0.0...
- Wrinkling Strains
- Thin pieces of wrought-iron under compression endwise may neither crush nor deflect (bend), but give way by wrinkling, that is, buckling or corrugating, provided there are no stiffening-ribs lengthwis...
- Lateral Flexure In Top Flanges Of Beams, Girders, Or Trusses, Due To Compression
- The usual formulae for rupture and deflection assume the beam, girder or truss to be supported against possible lateral flexure (bending sideways). Now, if the top chord of a truss or beam is comparat...
- Tension
- In tension the load is applied directly to the material, and it is, therefore, evident that no matter of what shape the material may be, the strain will always be the same. This strain, of course, wil...
- Cross-Shearing In Beams
- In transverse strains the (vertical) cross-shearing is generally not equal to the load, but varies at different points of the beam or cantilever. The manner of calculating transverse strains, however,...
- Table IV. Strength Of Materials Per Square Inch
- WOODS. Compression. Tension. Shearing. Modulus of Rupture. Modulus of Elasticity. e Weight per Cubic ft. Ultimate c Safe c/f Ultimate t Sa...
- Table V. Strength Of Stones, Bricks, And Cements Per Square Inch
- STONES. Compression on bed. Compression on edge. Tension. Modulus of Rupture. Weight per Cubic ft. Ultimate c Safe c/f Ultimate c1 Safe c1/f ...
- Table VI. Weight Per Cubic Foot Of Materials. (Not Included In Tables IV And V)
- Material. Weight. Ashes........... 59 Asphali........... 150 Butter........................ 60 Camphor........ 63 Charcoal.....
- Transverse Strength. - Rupture
- If a beam is supported at two ends, and loads are applied to the beam, it is evident: 1st, that the beam will bend under the load, or deflect. 2d, that if the loading continues, the beam will eventua...
- Reaction Of Supports
- If we imagine the loaded beam supported at both ends by two giants, it is evident that each giant would have to exert a certain amount of force upwards to keep his end of the beam from tipping. We can...
- The Principle Of Moments
- The law of the lever is well known. The distance of a force from its fulcrum or point where it takes effect is called its leverage. The effect of the force at such point is equal to the amount of the ...
- Greatest Bending Moment
- Where r = the moment of resistance in inches of the fibres at said point. Where (t/f) = the safe resistance to tension of the material, per square inch. The same formulae apply to cantilevers as wel...
- Rules For Calculating Transverse Strains
- 1. Find Reaction of each Support. If the loads on a girder are uniformly or symmetrically distributed, each support carries or reacts with a force equal to one-half of the total load. If the weights ...
- Comparative Strength And Stiffness Of Beams And Columns
- (1) If a beam supported at both ends and loaded uniformly will safely carry an amount of load =u; then will the same beam: (2) if both ends are built in solidly and load uniformly distributed, carry ...
- Table - Bending-Moment (M) And Amount Of Shearing-Strain (S)
- Uniform load on cantilever. m = u.l At free end use: m = o at support p at support p at free end s = o d = u/2 For x use: m ...
- Of Beams And Cantilevers For Various Loads
- Manner of Loading. Description. m and s at centre. m and s at any point distant x from support p. Location and amount of greatest bending-moment m. Location and amount o...
- Comparative Stiffness
- The stiffness of beams or cantilevers of same cross-section and material (and similarly loaded and supported), however, diminishes very rapidly, as the length of span increases, or what is the same th...
- Table VIII. Strength And Deflection Of Wooden Beams, One Inch Thick
- Spruce. Georgia pine. White pine. White oak. Hemlock Calculate (x) for transverse strength only if d is greater than 1 1/6L L 1 1/19L 1 1/5L...
- Plate Girders
- is Z,and x, be the strength of a column whose length is L1 ,then we have approximately x: x1 = L12:L2, or x1 = x.L2/L12 (34) Where x1, = approximately the strength of a column, L, feet long. Where x ...
- Expansion And Contraction Of Materials
- All long iron trusses, say about eighty feet long, or over, should not be built-in solidly at both ends; otherwise the expansion and contraction due to variations of the temperature will either burst ...
- Graphical Method Of Calculating 8trains. - Notation
- Notation. The calculation of strains in trusses and arches is based on the law Known as the Parallelogram of Forces. Before going into same it will be necessary to explain the notation used. If Fig....
- Parallelogram Of Forces
- If a ball lying at the point A, Fig. 19, is propelled by a power sufficient to drive it in the direction of B, and as far as B in one minute, and at B is again propelled by a power sufficient to drive...
- The Arch
- Fig. 29. We consider an arch as a truss with a succession of straight pieces; we can calculate it graphically the same as any other truss, only we will find that the absence of central or inner me...
- To Ascertain Amount Of Loads
- Let A B C D be a floor plan of a building, A B and C D are the walls, E and F the columns, with a girder between, the other lines being floor beams, all 12 between centres; on the left side a well-ho...
- Fatigue
- If a load or strain is applied to a material and then removed, the material is supposed to recover its first condition (provided it has not been strained beyond the limit of elasticity). This practica...
- Chapter II. Foundations
- Nature of Soils. The nature of the soils usually met with on building sites are: rock, gravel, sand, clay, loamy earth, made ground and marsh (soft wet soil). If the soil is hard and practically no...
- Foundations. Part 2
- Where, on account of party lines or other buildings, the stepping out of a foundation wall has to be done entirely at one side, the stepping should be even steeper than 60, if possible; and parti...
- Foundations. Part 3
- Clay is a good foundation, if in horizontal layers and of sufficient thickness to bear the superimposed weight. It is, however, a very treacherous material, and apt to swell and break up with water an...
- Chapter III. Cellar And Retaining Walls. Analytical Solution
- The architect is sometimes called upon to build retaining-walls in connection with terraces, ornamental bridges, city reservoirs, or similar problems. Then, too, all cellar walls, where not adjoining ...
- Cellar And Retaining Walls. Analytical Solution. Part 2
- Thus, if x = 33 and y = 50, formula (47) would become: p = w.L2/2. sin.2(17)o/sin2.50.o.sin.88o 1Above table of friction angles is taken from Klasen's Hockbau and Bruck-etibau - Constructi...
- Cellar And Retaining Walls. Analytical Solution. Part 3
- For reservoirs the line of pressure O P is always at right angles to the back surface of the wall, so that we can simplify formula (50) and use for rain water: p = 311/4. L2 (53) For salt water: p = ...
- Graphical Method
- Fig. 60. 1 Where a wall is not to be kept braced until the superimposed wall, etc., is on it, these should of course be entirely omitted from the calculation, and the wall must be made heavy enough...
- Graphical Method. Part 2
- When considering the weight per cubic foot of wall, we add the proportionate share of buttress; now in Figure 63 there are 4 cubic feet of buttress to every 7 feet of wall, so that we must add to the...
- Graphical Method. Part 3
- Cellar wall deeperthan adjoining building Fig. 67. The weight of the wall C G, per running foot of length, including floors and roofs, we find to be 13000 pounds, but to this we must add the possi...
- Graphical Method. Part 4
- We have, then, from Formula (44) stress at D1111; v =10375/44.12 + 6.16.10375/44.12.44=+63pounds. and from formula (45) stress at A1111; v =10375/44.12 - 6.16.10375/44.12.44= -23pounds. The joint A1...
- Chapter IV. Walls And Piers
- Walls are usually built of brick or stone, which are sometimes, though rarely, laid up dry, but usually with mortar filling all the joints. The object of mortar is threefold: 1. To keep out wet and c...
- Walls And Piers. Part 2
- In ordinary rubble stonework the mortar should be as strong as possible, as this class of work depends entirely on the mortar for its strength. For the strengths of different mortars, see Table V. S...
- Walls And Piers. Part 3
- slipjoints. mortar with generous top and bottom joints, to allow for shrinkage of the more frequent joints behind them; otherwise, they are apt to be shattered. Such unconstructional designs had, how...
- Walls And Piers. Part 4
- Timber of any kind, in walls, should be avoided, if possible. It should only be used for temporary support, as it is liable to rot, shrink, burn out, or to absorb dampness and swell, in either case ca...
- Walls And Piers. Part 5
- Regular work the best. The use of bond-stones at intervals only is bad; they should be carried through the whole surface (width and length) of wall and be of even thickness, or else be omitted. U...
- Walls And Piers. Part 6
- Underpinning. Fig. 82. This is readily seen, for the needles straighten out when relieved of the load. The jack-screws are now lowered or the wedges under the uprights eased up; the uprights taken...
- Walls And Piers. Part 7
- In all cases where asphalt is used, that with the least proportion of bitumen should be preferred. Seyssell asphalt, which comes from France, is undoubtedly the best, and next to this comes the Swiss ...
- Walls And Piers. Part 8
- For fair brick in' lime and cement (mixed) mortar, we should use: (c/f) = 50 And for the best brickwork in cement mortar, we should use: (c/f) = 200 If, however, a wall (or pier) is over 3 feet thi...
- Walls And Piers. Part 9
- Inserting the value of A from formula (61) we have: or the radius of flue will be 4 feet (diameter 8 feet). Now making the walls at top of chimney 8 thick and adopting the rule of an outside batte...
- Walls And Piers. Part 10
- Example. A two-story-and-attic dwelling has brick walls 12 inches thick; the walls carry two tiers of beams of 20 feet span; is the wall strong enough? The brickwork is good and laid in cement mortar...
- Walls And Piers. Part 11
- Thrust of barrels. A D2 - D B2 = A B2 or 4. D B2 - D B2 = w12 or Or, h = 0,578. w, (64) Where h = the horizontal thrust, in lbs., against each running foot of wall, w1 = one-half the total load, ...
- Walls And Piers. Part 12
- Use Formula (44) to get the stress at A, where x = K1 M1 = 9, or 3/4 feet; and p = G1 I1, which we find scales but little over 47 tons; and Formula (45) for stress at A. For d the width of joint we h...
- Chapter V. Arches
- The manner of laying arches has been de-scribed in the previous chapter, while in the first chapter was given the theory for calculating their strength; all that will be necessary, therefore, in this ...
- Arches. Part 2
- The width of joint is, of course, 8, and the area = 8 x 12 = 96 square inches; therefore, from Formula (44) Stress at edge J = 740/96 + 6. 740.1 1/2/96.8 = +16,26 and from (45) Stress at edge I = 7...
- Arches. Part 3
- Fig. 108. Therefore Stress at C = 11250/240 + 6. 11250.3 1/2/240 = +96 pounds, and Stress at D = 11250/240 - 6. 11250.3 1/2/240.20 = -3 pounds The arch is, therefore, safe. Example V. A 12-inc...
- Arches. Part 4
- Fig. 111. Stress at B = 19250/336 + 6. 19250.13/336.28 = + 217 pounds. And Stress at A = 19250/336 - 6. 19250/336.28 = - 102 pounds. The arch, therefore, cannot safely carry such heavy loads. Th...
- Arches. Part 5
- Use of buttress. Use of tie-rods. Example VIII. A semi-circular dome, circular in plan, is 40' inside diameter. The shell is 5' thick at the spring and 2' at the crown. The dome is of cut-stone. Wil...
- Arches. Part 6
- a = 160000/2.12000 = 6 2/3 Or we would use a band, say, 5 x 1 1/3. If dovetailed dowels of stone are used, as shown in Fig. 115, there should be one, of course, in every vertical joint. The dowel...
- Arches. Part 7
- 118) a o = g5 h5 = 4500 pounds and draw ob, oc, od, etc. We next construct the curve of pressure a K and find that it coincides as closely as possible with the centre line of the arch. This means that...
- Chapter VI. Floor Beams And Girders
- The writer has so often been asked for more information as to the meaning of the term Moment of Inertia that a few more words on this subject may not be out of place. All matter, if once set in motio...
- Resistance Of Fibres
- D1 C1 (Fig. 125) the base of the wedges becoming larger or smaller as the weight on the beam is varied. Now to proceed to the calculation of the resistance of this wedge. It is evident that whatever ...
- Resistance Of Fibres. Part 2
- Heart-Wood. Medullary Rays. Seasoning cracks. Fig. 126. Fig. 127. Fig. 128. Fig. 129. Fig. 130. Fig. 131. Vertical, or nearly vertical cracks (as C, Fig. 128) are not objectionabl...
- Resistance Of Fibres. Part 3
- In shrinking, the distance between rings remains onstant, and it is for this reason that the finest floors are made from quartered stuff; for (besides their greater beauty), the rings being all on end...
- Rectangular Beams
- For load at any point of beam. w1= b.d2.L/72.M.N . (k/f) (74) For uniform load on cantilever. u = b.d2/36.L. (k/f) (75) For load concentrated at end of cantilever. w = b.d2/72.L. (k/f) (76) For ...
- Rectangular Beams. Part 2
- In case the size of the beam is known, its safe span can, of course, be found by reversing the above procedure, or if the depth of beam and span is settled, we can find the necessary thickness and dis...
- Rectangular Beams. Part 3
- Heavier Floors. Basis of Tables XIV and XV. 1 The rule for calculating the exact thickness will be found later, Formula (78). The use of Table XV, is very similar to that of Table XIII, but that th...
- Lateral Flexure
- Where L = the length of clear span, in feet, that beam, etc., is unsupported sideways. Where b = the least breadth in inches of top flange, or Least thickness of beam, lintel or arch. Where y =a con...
- Lateral Flexure. Part 2
- Flitch-plate Cirder. Example. A Flitch-plate girder of 20-foot span consists of two Georgia pine beams each 6 X 16 with a sheet of plate-iron 16 deep bolted between them. The girder carries a lo...
- Lateral Flexure. Part 3
- = 0,718 Or the diameter of boll should be 1,436 or say 17-16. But 1 will be quite ample, as we must remember that the strains calculated will come only on the one bolt at the centre of span of be...
- Lateral Flexure. Part 4
- = L. 0,03 or = 30. 0,03 = 0,9. From Table IV we have for spruce: Calculation of Keyed girder. e = 850000 From Table I, Section No. 17, we have for' the weakest section of the girder, ...
- Lateral Flexure. Part 5
- inches. The end of girder should be deep enough to resist vertical shearing. In our case it is trifling, and we need not consider it. In all of these examples we have omitted the weight of the girder,...
- Table XVIII. Trussed Beams
- Illustrations. Description. Compression in Struts. Compression in Beam. Tension in Rods. Amount of Reactions. Trussed Beam with one centre load = w AB ...
- Trussed Beams. Part 2
- Where = the greatest deflection at centre, in inches, of a wrought-iron beam or plate girder of uniform cross-section throughout, and carrying its total safe uniform load, calculated for ruptur...
- Trussed Beams. Part 3
- Where w= the average strain, in pounds, in tension flange or chord of a beam, girder or truss of uniform cross-section throughout, and carrying its total safe uniform load. Where (t/f ) = the safe re...
- Trussed Beams. Part 4
- Where d = the total depth (height), in inches, from top of top flange or chord to bottom of bottom flange or chord. If girder or truss is of steel, use 1 3/5 instead of 1 7/8. We see therefore that ...
- Trussed Beams. Part 5
- 32300 = a. 750 or a = 32300/750 = 43 square inches. As the beam is 16 deep, this would mean an additional thickness - 43/16 = 2 11/16 Adding this to the 7 1/4 already found to be necessary, we ...
- Trussed Beams. Part 6
- Adding this to the above we should have the total deflection = 0,655+ 0,0125 = 0,6675 This would be the amount we should have to camber up the team, or say 3/4. The safe deflection not to ...
- Chapter VII. Graphical Analysis Of Transverse Strains
- A erent calculations to ascertain the amounts of bending-mo-ments, the required moments of resistance and inertia, the amounts of reactions, vertical shearing on beam, d e fl e c-tions, etc., can be d...
- Several Loads
- Having thus shown the basis of the graphical method of analyzing transverse strains, we will now give the actual method without wasting further space on proofs. it there are three loads w, w1 and w11...
- Several Loads. Continued
- = v1.l1,.zj.xy/e.i. (97) Amount of Deflection, Definite Pole Distance. Deflection varying Cross-section. Deflection Pole Distance arbitrary. 1 This would be the greatest possible deflection...
- Two Loads
- (Table IV; e= 800000 = 44.24180.750/800000.32 = 0,535 Had we calculated the deflection arithmetically from Formula (40) we should have had: = 1/48. 1000.1923/ 800000.333 = 0,548 or p...
- Five Concenteated Loads
- Select x distant x y= 1000 pounds from b a, (as 1000 = (k/f) for spruce, see Table IV). Draw xb, x h, xe, etc., and figure C D G. Draw xo parallel C G; it divides load line as follows: a o= 1580 pound...
- Five Concenteated Loads. Continued
- It would be: Cross shearing from A to w1 = 01H = 10000 pounds. Cross shearing from w1 to w11 = T I = 7500 ...
- Uniform And Concentrated Loads
- Fig. 157. Select pole x distant from load line at random (for the sake of illustration, though it would be better to make xy = (k/f) = 12000 pounds.) We find xy scales 6500 pounds. We now draw x b,...
- XII. Coor-Beams Per Square Foot Of Floor
- F SPAN IN FEET. Area of seet'n per sq. foot of floor. Area of Section per square foot of floor for each wood. . .10 . .11 . .12 . .13 . .14 . .15 ...
- Table XXI. And Steel Channels
- Use of this Table, see Table XIX. Axis Normal to Web. Intertia. (r) Moment of Resistance. (r) Square of Radius of Gyration. (2) Transverse Value (v) in lbs. ...
- XXII. Even-Legged Angles
- this Table, see Table XIX. Axis Parallel to One Side. xnci via. (r) Moment of Resistance. (r) Square of Radius of Gyration. (2) Distance of Centre of Gravity f...
- Table XXII. List Of Iron And Steel Even-Legged Angles
- (Fob Inbormation As To Use Of This Table, 3bb Tabls XIX.) MILLS ROLLING SHAPE. Size of Angle. Weight per Yard. Actual Length of Lege. Thickness. Area of each Leg. ...
- Table XXIII. List Of Iron And Steel Uneven-Legged Angles
- (For Information as to Use of this Table, see. Table XIX.) MILLS Rolling Shape. Size of Angle Weight pr Yard. Thickness of Logs. Actual Length of Long Leg. Actual Leng...
- XXIV. List Of Iron And Steel Tees
- (For Information as to the Use of this Table, see Table XLX.) Mills ROLLING SBAPE. Width of Flange (b) Depth over all. (a) Weight per Yard. Thickness of Flange. Ar...
- Preface to Vol2
- IN presenting the second volume of Safe Building to the public, a few words of explanation seem in place. In the preliminary announcement it was said that there might possibly be added, chapters o...
- Chapter VIII. The Nature And Uses Of Iron And Steel
- HE introduction of the use of iron into the construction of build-T ings has practically revolutionized modern architecture; the introduction of steel promises to make equally great changes. The cost ...
- The Nature And Uses Of Iron And Steel. Part 2
- Casting Pig-iron. Hot and Cold Blast. Charging Furnace. The air for the hot blast is heated by passing it through the above mentioned iron pipes around which the gases play ; or, where the brick ch...
- The Nature And Uses Of Iron And Steel. Part 3
- For rolling or mill work the most used are the Nos. 2 and 3, Grey Forge and Mottled of the mill irons. For castings the most used are the Nos. 1, 2 and 3 and Grey Forge of foundry irons; the Mottled a...
- Table XXVI. Analysis Of Cast Irons
- Combined Carbon. Graphitic Carbon. Silicon. Greatest softness..... 0,15 3,1 2,5 hardness... - - under 0,8 ge...
- Table XXVII. Densities And Weights Of Cast Irons
- Material. Density. Weight per cubic foot in lbs. Dark-grey foundry-iron...... 6,80 425 Grey foundry-iron......... 7,20 450 Mottled foundr...
- Densities And Weights Of Cast Irons. Part 2
- Another serious objection to uneven thickness in castings is the uneven cooling; that is, the thin parts cool before the thicker ones, and the consequence is the production of internal strains in the ...
- Densities And Weights Of Cast Irons. Part 3
- Avoid all sharp angles- Shrinkage in Castings. Steel-castings. Manufacture of Wrought-iron. Refining and Puddling. When beams or other rolled-iron shapes are to be rolled the cold muck bars arc s...
- Densities And Weights Of Cast Irons. Part 4
- Straightening the Pieces. Single Refined-iron. For very important tension-members in trusses or arches, or for important hangers it is very desirable to use the double refined-iron. But, as a rule, ...
- Densities And Weights Of Cast Irons. Part 5
- There is a quality of iron known as malleable cast-iron, which combines, to a certain extent, the qualities of both wrought and cast iron, being cast-iron of a semi-wrought-iron character, which can b...
- Densities And Weights Of Cast Irons. Part 6
- Steel rolled colder than Iron. Direct Process. Two Principal Methods. Cast-steel. Open Hearth Process. OPEN-HEARTH PROCESS. It consists of melting a combination of irons in a basin-shaped hearth...
- Densities And Weights Of Cast Irons. Part 7
- Taking all things together, however, the superiority to-day for structural iron seems to lie with steel metal made under the Open Hearth process, (first introduced into this country by the New Jersey ...
- Table XXVIII. Classification Of Irons And Steels
- Name. Percentage of Carbon. Properties. 1. Malleable iron. 0,25 Is not sensibly hardened by sudden cooling. 2. Steely iron. 0,35 Can...
- Classification Of Irons And Steels. Part 2
- Malleable Cast-iron. Wrought-iron. Hard and Soft Steel. Soft mild steels have a tenacity and resistance to compression, and an elastic limit somewhat (proportionately much) higher than wrought-...
- Classification Of Irons And Steels. Part 3
- All parts which are planed and are to make exact joints, and cannot, therefore, be painted, should be kept carefully covered at all times until erection with a heavy coating of lard and white lead mix...
- Classification Of Irons And Steels. Part 4
- However, the whole subject is very uncertain, the increase or decrease of strength by re-meltings depending evidently on the particular mixture of iron used. A test in each case would be the only reli...
- Classification Of Irons And Steels. Part 5
- Avoid Blue-heat. With steel the tensional, transverse and compressive stresses vary greatly with the composition of the material. As already stated the more carbon it contains, the less elastic, but ...
- Classification Of Irons And Steels. Part 6
- In iron and steel the principal tests resorted to are for tensional strength, elasticity, ductility and limit of elasticity. These will be explained presently. The nature of the material can also be m...
- Classification Of Irons And Steels. Part 7
- In very hard materials it is more than half the strain, for such materials not being elastic, will stretch (or shorten) but very little and will not show appreciable variation until a high strain is r...
- Table XXX. Amount Of Extension And Contraction, In Inches, Of Cast And Wrought Iron Bars, 100 Ft. Long, Under Different Strains
- Strain, per square inch, in pounds. CAST IRON. WROUGHT IRON. Extension, under tension. Contraction, under compression. Extension, under tension or contraction, under...
- Table XXXI. Length Of Cast Or Wrought Iron Bars, In Feet, That Will, Stretch Or Contract Exactly One Inch Under Different Strains
- Strain, in pounds, per square inch. CAST IRON. WROUGHT IRON. Length, in feet, to extend one inch. Length, in feet, to shorten one inch. Length, in feet, to either ex...
- Table XXXII. Ultimate Breaking Strength Of Materials Under Different Kinds Of Strains
- Material. If Dead Lond (Static). Intermittent Loads (off-and-on continuously.) If in one direction only. If in opposite directions. Without shock. Rolling ...
- Ultimate Breaking Strength Of Materials Under Different Kinds Of Strains. Continued
- In pieced work where angles are attached to beams, etc., if it is punched and fitted together at the mill with bolts the whole will be charged at a standard rate per pound ; if, however, the pieces ar...
- Postscript To Chapter VIII
- Since writing the foregoing chapter a claim has been made by J. W. Bookwalter, an iron manufacturer of Springfield, Ohio, to have perfected a new process which will revolutionize the manufacture of ir...
- Chapter IX. Rivets, Riveting And Pins
- WHEN it is necessary to secure two or more pieces of iron or steel together in such a manner that they can be readily separated, bolts are used. These are iron or steel pins with solid heads at one en...
- Rivets, Riveting And Pins. Part 2
- In drilled-work there is no loss, and the holes are not only accurately located but are accurately cut. But drilled-work is very expensive, as it has to be done by hand or by machine-drills, the proce...
- Rivets, Riveting And Pins. Part 3
- In wrought-iron the loss is about 15 per cent. In steel the strength of the rivets will depend greatly upon the composition and nature of the steel itself, but in order to be able to rivet, the steel ...
- Rivets, Riveting And Pins. Part 4
- Fig. 163. Butt joint with cover-plates. Two cover-plates best. 5 each 7/8 inch rivet of 5/f and if f= 5 (or a factor-of-safety of 5 were used) it would add just one ton to the calculated strength...
- Rivets, Riveting And Pins. Part 5
- Cover-plates, as in Figure 170, should each be the full width of original plates and at least one-half the thickness of same; in practice they too are each made about 1/16 inch (or more) thicker. The...
- Rivets, Riveting And Pins. Part 6
- For Wrought-iron. ( c/f) = 12000 pounds, per square inch. (t/f ) = 12000 pounds, per square inch. ( g/f ) = 8000 pounds, per square inch. (k/f) = 15000 pounds, per square inch. For Steel. (c/f) = 5...
- Rivets, Riveting And Pins. Part 7
- Of course, the rivets must be of steel too. We will again assume that we can stagger the rivets, so that we shall lose only one rivet-hole. The plate will evidently have to be thick and we will decid...
- Rivets, Riveting And Pins. Part 8
- For bending-moment we should have a 1 circular beam with a clear span of 1, uniformity loaded with 135000 pounds. From Formula (21) we have the bending-moment m = 135000.1/8= 16875 pounds-inch Mom...
- Rivets, Riveting And Pins. Part 9
- (g/f) for steel as = 15000 pounds, instead of 10000 pounds, can take the curve marked 15000 pounds - tension steel, in any of the three tables. Or, if he wishes to Figure his iron at only 10000 pou...
- Rivets, Riveting And Pins. Part 10
- Bending-moment Curve. Bearing on pins. The safe shearing value for a 2 inch wrought-iron pin, would be from Table XXXIX= 25000 pounds, and for steel 31670 pounds. By calculation we should have had f...
- Rivets, Riveting And Pins. Part 11
- Arrangement of Heads. Fig. 178. Fig. 179. -with a free end carrying load e; the beam being loaded with three loads, two each =c/2 and one = b. To calculate the bending-moment at any point of t...
- Rivets, Riveting And Pins. Part 12
- It is customary, therefore, to locate the forces along the pin symmetrically, regardless of their true resistances as they would be if treated as continuous girders, and to consider, that each takes i...
- Rivets, Riveting And Pins. Part 13
- By referring to a table of areas of circles, or by calculation we find ing-moment. We have marked along the pin, Figure 187, the thicknesses of heads, the length of pin required being 5 1/2, to this ...
- Rivets, Riveting And Pins. Part 14
- Divide largest force. Forces will equalize themselves. The bearing of these heads against the pin we know are all right, also the shearing, as the greatest shearing under this arrangement will be a ...
- Rivets, Riveting And Pins. Part 15
- Thus, if we take the pin and forces shown in Figure 189, we should change the notation to that adopted for the graphical method, which would be as shown in Figure 193. That is force E (22000 pounds) o...
- Chapter X. Plate And Box Girders
- WHEN it becomes necessary to cover floors or spaces of such large span, or to carry loads so heavy, that rolled-beams will not answer the purpose, girders are made up of plates and angles riveted toge...
- Plate And Box Girders. Part 2
- Number of rivets in web leg of angles. Frequently many more rivets will have to be used than are required by calculation in order not to exceed the greatest pitch for rivets given in Formula (107). ...
- Plate And Box Girders. Part 3
- Figure 197 shows clearly the way in which rivets are strained. The web-rivet, No. 3, is bearing against web on the surface E F and against angles on the two surfaces (sum of) DE and FG Value of rive...
- Plate And Box Girders. Part 4
- As a rule the angles are made in one piece from end to end, as they can easily be obtained of great length, and are awkward to splice. Angles should be used as heavy as possible, but if very thick the...
- Plate And Box Girders. Part 5
- This, however, is probably an extreme case. The writer would recommend that the following be used, where no experiments can be made: For wrought-iron plate girders e= 18000000 pounds-inch. For mild-s...
- Plate And Box Girders. Part 6
- 139/19 1/4 = 7,22 tons. We now take Table XLIII, pass down the 60' 0 vertical line till we strike the curve 36 and then pass to the left to find the above value 7,22 tons. We strike the curve on t...
- Plate And Box Girders. Part 7
- N, 0,P, Q, R, and S with the curve are the points at which the respective plates can be broken off. We shall, however, carry the first plate NO the entire length, and as this plate is spliced inside ...
- Plate And Box Girders. Part 8
- For end stiffeners we use Formula (125) s = 182500 - 12000.5/8.16/1+0,0003.362/(5/8)2 = 122500 pounds. Or we should need 122500/6562 = 18,6 Or we should need some 19 rivets in the end stiffener, w...
- Plate And Box Girders. Part 9
- = 5/384.357500.7083/18000000.58000 = 1,62 Or, practically the same result, and showing how closely the different methods agree. Had we Figured the girder arithmetically we should have obtained...
- Chapter XI. Graphical Analysis Of Strains In Trusses
- HE same general rules which apply to beams and girders apply T equally well to trusses ; but as the latter are made up of a large number of parts, some sustaining the loads directly, others transmitti...
- Table XLIV. Table Of Wind Pressures On Roofs
- Angle of Inclination of Rafters with Horizon. Pressure or Load, in pounds, per square foot of Roof Surface. 10 9 2/3 15 14 20 18J ...
- Table Of Wind Pressures On Roofs. Part 2
- Superfluous members. CE, HG and G B; and in strain diagram; be, downwards, therefore a vertical load; c h downwards towards joint, therefore compression ; h g to the left, towards joint, therefor...
- Table Of Wind Pressures On Roofs. Part 3
- Figures 213 to 219 are best adapted to wood, or wood and iron construction ; while Figures 220 to 228 are best adapted to iron construction, they being on the principle of a pair of inclined trussed b...
- Table Of Wind Pressures On Roofs. Part 4
- Arched Trusses. Fig. 235a. Fig. 235 b. Fig. 235 a1. Fig 235 b1. In separating the truss we note that in Figure 239, we have the additional tension member JI (see Figure 229) ; and in Fi...
- Table Of Wind Pressures On Roofs. Part 5
- Hammer-beam Truss. FlG.243. Increased stress in curved members. m = s.x (129) Where m = the (cross) bending-moment, in pounds-inch, existing in a curved strut or tie at its centre due to long...
- Table Of Wind Pressures On Roofs. Part 6
- That these strains just equal each other is due to the design of the truss and its uniform loading. Were the design of the parts less symmetrical, or the load not symmetrical, or the wind on one side ...
- Table Of Wind Pressures On Roofs. Part 7
- Fig. 251a. If, however, one foot only were bolted down and the other foot were placed on rollers, to allow lor expansion and contraetion, we should have to make, two diagrams, with the wind from ...
- Table Of Wind Pressures On Roofs. Part 8
- Similarly G F would become tension if the wind were from the left. We will consider the tendency of wind to overturn roofs, and this can best be done by calculating one or two practical examples of s...
- Table Of Wind Pressures On Roofs. Part 9
- Fig. 255. The way to put in such rods is to leave the lower end free to move vertically, that is up and down, but secure it against lateral movement and then to attach to the lower end a heavy we...
- Chapter XII. Wooden And Iron Trusses
- IN Figure 256 we have the design of one-half of an ordinary kingpost truss, with three bays to each principal rafter. Figure 257 gives the strain diagram and Figure 258 the design of the truss in deta...
- Wooden And Iron Trusses. Part 2
- Vertical load on slanting beam. Tie-beam. Struts. Nature of com pression large blocks. Where, therefore, we are proportioning the sizes of struts - or later the sizes of washers - for their bearin...
- Wooden And Iron Trusses. Part 3
- Bearing area. Bolt at foot. Calculating strap. 54000/2=27000 pounds on each. The safe shearing stress on wrought-iron being 8000 pounds per square inch (see Table IV) we need an area at each angle ...
- Table Of Strains Of Roof
- Name of piece. Standing load. Wind load. Result. B.J. + 76000 + 8000 + 84500 G. K. + 61000 + 8500 + 69500 D. L. + 460...
- Table Of Strains Of Roof. Part 2
- We now lay out, Figure 269, the pin, and find that we have a double lever arrangement ; the fulcrum being the 2 inch wide 67000 pounds strain. To the left of this we have a lever 1 3/4 inch wide loade...
- Table Of Strains Of Roof. Part 3
- Formula (21) m = 67000.2/8 = 16750 pounds-inch. Therefore number of rivets required to resist bending-moment = 16750/987= 16,9 or say nine each side of joint. The plate, however, requires ten each s...
- Chapter XIII. Columns
- THE Formula (3) on page 24 of Vol. I, is, of course, applicable this value for pin that is, rounded or rough bearings at ends, and for smooth that is, turned, planed or smoothed off bearings at en...
- Columns. Part 2
- Figure 276. To prevent fi r e spreading up t h r o u g h columns, some building laws require solid plates at all joints; in such cases they should be made Caps and bases. FlG. 278. Bottom plates...
- Columns. Part 3
- Shapes of wrought-iron columns. Figure 281 is more easily riveted up than 280, but is not quite as strong. Figure 282 shows an elevation with wrought-iron base, and Figure 283 the side view of base....
- Table XLIX. Safe Compressive Loads Per Square Inch On Wrought-Iron Columns
- RATIOOF (IN INCHES.) Square of length to square of radius of gyration. Length to radius of gyration. 100 10 225 15 400 20 625 ...
- Table L. Properties Of Phoenix Columns
- Thickness in ins. d inside. d outside. d1 over flanges. Area of cross section sq. in. Least radius of gyration in ins. 3/16 A-3 5/8 4 6 1/16 ...
- Table LI. Natural Sines, Etc
- Degree. For angles under 45. Sine. Covers. Cosecnt. Tangt. Cotang. Secant. Versin. Cosine. 0 0,00000 1,00000 Inf...
- Table LII. Natural Sines, Tangents And Secants, Advancing By 10 Min
- Deg. Min. Sine. Tangent. Secant. 0 00 ,0000 ,0000 1,0000 10 ,0029 ,0029 1,0000 20 ,0058 ,0058 ...
- Table LIII. Logarithms Of Numbers
- No. 0 1 2 3 4 5 6 7 8 9 Diff. 10 0000 0043 0086 0128 0170 0212 0253 0294 0334 03...
- Table LIV. Squares, Cubes, Square And Cube Roots And Reciprocals Of Numbers
- No. Square. Cube. Sq. Root. Cube Root. Reciprocal. 1 1 1 1, 1, 1,000000000 2 4 8 1,414214 1,259921 ,5...
- Table LV. Multiplication Table In Inches For Rectangular Sections
- Thickness in inches. 1 1 1/4 1 1/2 1 3/4 2 2 1/4 2 1/2 2 3/4 3 3 1/4 3 1/2 3 3/4 4 4 1/2 4 1/2 4 3/...
- Table LVI. Circumferences And Areas Of Circles From 0 To 100, Also Squares Up To 12
- Diameter or side. Circumference. Area. Square. 0 1/16 ,1963 ,0031 ,0039 1/8 ,3927 ,0123 ,0156 3/16 ...
- Table LVII. Decimal Parts Of Ax Inch For Each 1/64 Of An Inch
- Fraction. Decimal. 1/64 0,015625 1/32 0,03125 3/64 0,046875 1/16 0,0625 5/16 0,078125 3/32 0,09375 ...
- Table LVIII. Decimal Parts Of A Foot For Each 1/64 Of An Inch, From 0" To 12"
- Inch. 0 1 2 3 4 5 6 7 8 9 10 11 0 0 ,0833 ,1667 ,2500 ,3333 ,4167 ,5000 ,...
- Table LIX. Reduction Of English Feet And Inches To Metres
- 0 1 2 3 4 5 6 7 8 9 10 11 0' 0 0,025 0,051 0,076 0,102 0,127 0,152 0,178 ...
- Table LX. Reduction Of English Inches To Millimetres
- 1/32 0,79 1/16 1,59 3/32' 2,38 1/8 3,17 5/32 3,97 3/16 4,76 7/32 5,56 1/4 6,35 ...
- Table LXI. Reduction Of English Weights To Kilograms
- LBS. Kilos. 1 0,454 2 0,907 3 1,361 4 1,814 5 2,268 6 2,722 7 3,175 8 3,629 ...
- Table LXII. English Measures And Weights. (U. S. Standards Are The Same.) Long Measure
- 12 inches = 1 foot. 3 feet = 1 yard. 16 1/2, feet = 5 1/2 yards = 1 rod, or pole, or perch. 660 feet = 220 yards = 40 rods= 1 f...
- Table XXXI. Length Of Cast Or Wrought Iron Bars, In Feet, That Will Stretch Or Contract Exactly One Inch Under Different Strains
- Strain, in pounds, per square inch. CAST IRON. WROUGHT IRON. Length, in feet, to extend one inch. Length, in feet, to shorten one inch. Length, in feet, to cither ex...
- Table XXXIII. Proportions For
- SCREW THREADS, NUTS, and BOLT HEADS. Diameter of Screw. Threads per Inch. Diameter at root of Width of Flat, Short Diameter Rough. Short Diameter ...
- Table XXXIV. Recent Tests Of Irons And Steels
- Material. Remarks. Per Cent, of Modulus of Elasticity, in pounds-inch, for Tension, in pounds, per square inch. Compression, in pounds, per square inch. Ult...
- Table XLII Wrought Iron Riveted Girders.-Strength Of The Angle Bars
- If Angle Bars are of Steel all Rivets Must be of Steel. Fob Steel Angle Bars Add one quarter to safe load on iron bars, but length of span (in feet) must not exceed twice the depth of girder (in i...
- Table XLIII. Wrought Iron Riveted Girders. Strength Of Flanges
- To Obtain the Actual Strength of Flange is Tons. Multiply the safe uniform load (U) by the effective width of flange, that is, the total width of either flange, less the greatest number of rivet ho...
- Books By Louis De Coppet Berg
- SAFE BUILDING. Series I. Square 8vo. Illustrated with numerous formulas, diagrams and tables. $5.00. The author furnishes to any earnest student the opportunity to acquire, so far as books will tea...
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