UC-NRLF SB 573 in oo o LIBRARY OF THE UNIVERSITY OF CALIFORNIA. Class m "The simplest natural objects have bearings which calculation does not touch, and appearances and relations which definition fails to include." General Specifications FOB Steel Roofs and Buildings. FOURTH REVISED EDITION. With Tables. 19OI CHARLES EVAN FOWLER, M. Am. Soc. E. N*v fc&UFQf^ Diagram. *y: GENERAL SP&GIFIGftTIONS FOR STEEL ROOFS flND BUILDINGS. CHARLES EVAN FOWLER, M. AM. Soc. C. E. FOURTH REVISED EDITION 1899- GENERAL DESCRIPTION. 1. The structure shall be of the general outline and dimen- sions shown on the attached diagram, which gives the principal dimensions and all the principal data. (2, 72.) 2. The sizes and sections of all members, together with the strains which come upon them, shall be marked in their proper places upon a strain sheet, and submitted with proposal. (X 72.) 3. The height of the building shall mean the distance from clearances, top of masonry to under -side of bottom chord of truss. The width and length of building shall mean the extreme distance out to out of framing or sheeting. 4. The pitch of roof shall generally be one fourth. (6.) LOADS. The trusses shall be figured to carry the following loads: 5. SNOW LOADS. PITCH OF ROOF. LOCATION. 1-2 i-3 1-4 i-5 1-6 Southern States and Pacific Slope . Central States * O O O O n o 7 10 10 12 o 15 20 2O 2C O 22 27 35 17 o 30 35 45 CO Rocky Mountain States .... New England States ...... Northwest States Snow Load. Pounds per hor. sq. foot. 6. The wind pressure on trusses in pounds per square foot wind Load, shall be taken from the following table: Pitch Vertical Horizontal i-2=45oo' 19 19 i-3 = 334i' 17 12 i-4=2634' 15 8 i-5 = 2i48' 13 6 i-6=i826' n 4 7. The sides and ends of buildings shall uniformly distributed wind load of 2O pounds of exposed surtace when 20 feet or less Normal. 27 22 18 15 13 (70 be figured for a per square foot to the eaves; 30 the pounds per square foot of exposed surface when 60 feet to eaves, and proportionately for intermediate heights. (6.) ering Weight of cov- 8. The weight of covering may be taken as .follows: Cor- rugated iron laid, black and painted, per square foot: No. 27 26 24 22 20 18 16 .90 i.oo 1.30 i. 60 1.90 2.60 3. 30 pounds. For galvanized iron add 0.2 pounds per square foot to above figures. Slate shall be taken at a weight of 7 pounds per square foot for 3-16" -slate 6" x 12", and 8.25 pounds per square foot for 3-16" slate I2"x24", and proportionately for other sizes. Sheeting of dry pine boards at three pounds per" foot board measure. Plastered ceiling hung below at not less than 10 pounds per square foot. The exact weight of purlins shall be calculated. 9. The weight of Fink roof trusses up to 200 feet span may be calculated by the following formulas, for preliminary value. w=.c6 s-j-,6, for heavy loads. w=.Q4 S+.4, for light loads. (40, 45.) s=span in feet. w= weight per hor. sq. ft. in pounds. 10. Mill buildings, or any that are subject to corrosive action of gases, shall have all the above loads increased 25 per cent. 11. Buildings or parts of buildings subject to strains from machinery or other loads not mentioned, shall have the proper allowance made. 12. No roof shall, however, be calculated for a less load than 30 pounds per horizontal square foot. Weight of Trusses Increase of Loads. Minimum Load. UNIT STRAINS. Iron. Tension only. j^. Shapes, net section , . . . Bars 14000 Bottom flanges of rolled beams Laterals of angles, net section . Laterals of bar 18000 Soft-Medium. Steel 15000 17000 15000 2000O (57) (57) uo Compression only. Flanges. "Combined. 14. Flat ends and fixed ends . , , . . 12500^500 f /=length in feet c. to c. of connections. r least radius of gyration in inches. (59) 15. Top flanges of built girders shall have the same gross area as tension flanges. (24) 16. Members subject to transverse loading in addition to direct strain, such as rafters, and posts having knee braces con- nected to them, shall be considered as fixed at the ends in rivit- ed work, and shall be proportioned by the following formulae, and the unit strain in extreme fibre shall not exceed for soft medium steel: 15000 Ma P ^ _ _ _i_ _ , I A (52, 62.) 5 =Strain per square inch in extreme fibre. M Moment of transverse force in inch pounds, n Distance center of gravity to top or bottom of final section in inches. I Final moment of inertia. P -Direct load. A Final area. Soft- Medium Soft Steel. Steel. Sheari 17. Pins and rivets ..... 10000 (57) Web plates ...... 7000 18. On ciia. of pins and rivet holes 20000 20000 (57) * 19. Extreme fibre of pins . . . 25000 Extreme fibre of purlins . . 15000 (49) 20. Lateral connections will have 25 per cent greater unit strains than above. 21. Bolts may be used for field connections at two-thirds of Bolts - rivet values. (17, 18.) TIMBER PURLINS 22. In purlins of yellow pine, southern pine or white oak, Timber - the extreme fibre strain shall not exceed 1200 Ibs. sq. iri. (50) PLATE GIRDERS. 23. The length of span shall be considered as the distance Girders - from, center to center of end bearings when girders rest on bottom flange, and from end to end when fastened between columns by connection angles. 24. The compression flanges shall be stayed transversely F i an es - when their length 'is more than thirty times their width. (15) One-sixth of the web shall be included as flange area, provided proper horizontal splices are made at web joints. 25. All web plates shall be stiffened at the inner and outer stiffeners. edges of the end bearings and at all points of local concentrated loading. Intermediate stiffeners shall be used provided the shearing strain per square inch exceeds that given by the formula: 15000 d* d= Clear dist. between flange angles in inches. i -| --- - t Thickness of web in inches. 3000/ 2 CORRUGATED IRON COVERING. 26. Corrugated iron shall generally be of 2^ inch corruga- tions, and the gage in U. S. standard shall be shown on strain sheet, 27. The span or distance center to center of roof purlins shall not exceed that given in the following table: 27 gage . . . 2' o" 20 gage . . . 4' 6" 26 gage .. . . 2' 6" iSgage . . . $'o" 24 gage . . . 3' o" 16 gage , . , 5' 6" 22 gage . . . 4' o" (48) 28. All corrugated iron shall be laid with one corrugation side lap, and not less than four inches end lap, generally with six inches end lap. (32) 29. AH valleys or junctions shall have flashing extending at least 12 inches under the corrugated iron,or 12 inches above line where water will stand. (35, 36.) 30. All ridges shall have roll cap securely fastened over the corrugated iron. Fastenings 3^ Corrugated iron shall preferably be secured to the purlin by galvanized straps of not less than five-eighths of an inch wide by No. 18 gage; these shall pass completely around the purlin, and have each end riveted to the sheet. There shall be at least two fastenings on each purlin for each sheet. 32. The side laps shall be riveted with six pound rivets not more than six inches apart. (28.) Finish An ff ie ^$. At the gable ends the corrugated iron shall be securely fastened down on the roof, to a finish angle or channel, connect- ed to the end of the roof purlins. VENTILATORS AND LOUVRES. Ventilators 34. Ventilators shall be provided and located so as to properly ventilate the building. They shal! have a net area of openings for each 100 square feet of floor surface of not less than one- half a square foot for machine shops, of not less than five square feet for mill buildings and not less than seven square feet for forge shops. louvres Louvres shall be provided in ventilators, if necessary, of such form as to prevent the blowing in of snow or storm watet, and of a stiff enough section not to sag below hoizontal and appear un- sightly. They shall be not less than No. 16 gage galvanized for flat louvres* and No. 20 gage galvanized for corrugated lou- vres. LIGHTING. windows 35. Windows shall be provided in the sides and clearstory or ventilator of a surface equal to not less than 10 per cent of the entire exterior surface of the buildings, in mill buildings, and of not less than 20 per cent in machine .shops or similiar build- ings. (29) Skylights 36. At least half of the lighting specified shall preferably be in the form of sky lights of some form of construction which shall entirely prohibit leaking. (29) 5 DETAILS OF CONSTRUCTION. 37. All tension members shall preferably be composed of Tension Mem- angles or shapes with the object of stiffness. bers * 38. All joints shall have full splices and not rely on gussets. (650 39. All main members shall preferably be made of two angles, back to back, two angles and one plate, or four angles laced. (67.) 40. Secondary members shall preferably be' made of sym- metrical sections. 41. Long laterals or sway rods may be made of bar, with sleeve nut adjustment, to facilitate erection. 42. Members having such a length as to cause them to sag shall be held up by sag ties of angles, properly spaced. 43. Rafters shall preferably be made of two angles, two Compression angles and one plate, or of such form as to allow of easy connec- tion for web members. (65.) 44. All other compression members, except sub-struts, shall be composed of sections symmetrically disposed. (65.) 45. Sub-struts shall preferably be made of symmetrical sec- tions. 46. The trusses shall be spaced, if possible, at such distances Purlin9 - apart as to allow of single pieces of shape iron being used for purlins, trussed purlins being avoided, if possible. Purlins shall preferably be composed of single angles, with the long leg verti- cal and the back toward the peak of the roof. 47. Purlins shall be attached to the rafters or columns by clips, with at least two rivets in rafter and two holes for each end of each purlin. 48. Roof purlins shall be spaced at distances apart not to ex- ceed the span given under the head of Corrugated Iron. (27.) 49. Purlins extending in one piece over two or more panels, laid to break joint, and riveted at ends, may be figured as con- tinuous. 50. Timber purlins, if used, shall be attached in the same manner as steel purlins. 51. Sway bracing shall be introduced at such points as is sway Bracing- necessary to insure ease of erection and sufficient transverse and longitudinal strength. (41.) 52. All such strains shall preferably be carried to the founda- tion direct, but may be accounted for by bending in the columns. (62.) $3. Bed plates shall never be less thar one-half inch in B ed Plates, thickness, and shall be of sufficient thickness and size so that the pressure on masonry will not exceed 300 pounds per square inch. Trusses over 75 feet span on walls or masonry shall have expansion rollers if necessary. (54.) Punching and Reaming 1 . Effective Diameter of Rivets. Pitch of Rivets. Anchor Bolts. 54. Each bearing plate shall be provided with two anchor bolts of not less than three-fourths of an inch in diameter, either built into the masonry or extending far enough into the masonry to make them effective. (53.) Punching. 55, The diameter of the punch shall not exceed the diamter of the rivet, nor the diameter of the die exceed the diameter of the punch by more than one-sixteenth of an inch. (56.) 56. All rivet holes in steel may be punched, and in case holes do not match in assembled members they shall be reamed out with power reamers. (71.) 57. The effective diameter of the driven rivet shall be as- sumed the same as before driving, and in making deductions for rivet holes in tension members, the hole will be assumed one eighth of an inch larger than the undriven rivet. (13,17.) 58. The pitch of rivets shall not exceed twenty times the thickness of the plate in the line of strain, nor forty times the thickness at right angles to the line of strain. It shall never be less than three diameters of the 1 rivet. At the ends of compres- sion members it shall not exceed four diameters of the rivet for a length equal to the width of the members. $9. No compression member shall have a length exceeding fifty times its least width, unless its unit strain is reduced accordingly. (14-) 60. Laced compression members shall be stayed at the ends by batten plates having a length not less than the depth of the member. 61. The sizes of lacing bars shall not be less than that given in the following table, when the distance between the gage lines is (62.) 6" or less than 8" . 8" or less than 10" . 10" or less than 12" . . 12" or less than 16" . . 16" or less than 20" . 20" or less than 24" . . 24" or above of angles. They shall generally be inclined at 45 degress to the axis of the member, but shall not be spaced so as to reduce the strength of the member as a whole. 62. Where laced members are subjected to bending, the size of lacing bars or angles shall be calculated or a solid Veb plate used. (13, 14, 61.) 63. All rods having screw ends shall be upset to standard size, or have due allowance made. 64. No. metal of less thickness than ^ inch shall be used, except as fillers, and no angles of less than 2 inch leg. A varia- tion of 3 per cent shall be allowable in the weight or cross sec- tion of material. I 1-4" x 1-4" I I-2"X 1-4" 1 3-4" x 5-16" 2" x 3-8" 2 1-4" x 7-16" WORKMANSHIP. 65. All workmanship shall be first class in every particular. All abutting surfaces of compression members, except where the joints are fully spliced, must be planed to even bearing so as to give close contact throughout. (38.) 66. All planed or turned surfaces left exposed must be pro- tected by white lead and tallow. (89) 67. Rivet holes for splices must be so accurately spaced that Rivet8 the holes will, come exactly opposite when the members are brought into position for driving rivets, or else reamed out. (38, 70, 71.) 68. Rivets must completely fill the holes and have full heads concentric with the rivet holes. They shall have full contact with the surface, or b countersunk when so required, and shall be machine driven When possible. Rivets must not be used in direct tension. 69. Built members when finished must be free from twists, open joints or other defects. (65.) 70. Drift pins must only be used for bringing the pieces to- Drillln ** gether, and they must not be driven so hard as to distort the metal. (71.) 71. When holes need enlarging, it must be done by ream- Rcami - ing and not by drifting. (70.) 72. The decision of the engineer or architect shall control as Drawings and as to the interpretation of the drawings and specifications during speclfi< the progress of the work. But this shall not deprive the contractor of right of redress after work is completed, if the de- cision shall be proven wrong, (i, 91,95.) QUALITY OF MATERIAL. WROUGHT IRON 73. All wrought iron must be tough, ductile, fibrous and of c * a . r * c * er and uniform quality. Finished bars must be thoroughly welded during the rolling, and be straight, smooth and free from in- jurious seams, blisters, buckles, cracks or imperfect edges. 74. No one process of manufacture is preferred over another, Manufacture, provided the material complies with this specification. 75. For tension tests the test piece shall have as near one- standard Test half square inch of sectional area as possible, and a length of at Pleces> least 8 inches with uniform section, for determining the elongation. 76. The elastic limit shall be not less than 26,000 pounds per Elastic Limit square inch for all classes of iron. 77. Standard test pieces from iron having a section of 4^ Teasion Iron square inches or less shall show an ultimate strength of not less than 50,000 pounds per square inch and an elongation in 8 inches of not less than 18 per cent. 8 78. Standard test pieces from bars of more than 4^ square inches section will be allowed a reduction of 500 pounds for each additional square inch of section, provided the ultimate strength does not fall below 48,000 pounds or the elongation in 8 inches below 15 per cent. 79. All iron for tension members must bend cold through 90 degrees to a curve whose diameter is not over twice the thickness of the piece, without cracking. 80. Not less than one sample out of three shall bend cold to this curve through 180 degrees, without cracking. 81. When nicked on one side and bent by a blow from a sledge, the fracture must be wholly fibrous. STEEL. Manufacture. 82. Steel made either by the Bessemer or Open Hearth pro- cess of manufacture shall be acceptable. 8 3* Test Pieces for tension and bending tests shall have as near one-half square inch of sectional area as possible and a length of at least 8 inches with uniform section, for determiming elongation. 84. One test piece for tension and one for bending are to be taken from each heat or blow of finished material. Finish.. 85. Finished bars must be free from flaws, cracks or injurious seams and have a first-class finish. Grades g of^ g t Steel of soft and soft-medium grades only are to be used, the soft steel for rivets and offset or bent angles or plates, and soft-medium for all other parts where iron is not optional. Phosphorus The phosphorus shall never exceed in any steel 0.08 per cent., nd Limu phnr nor the sulphur 0.04 per cent. (56.) soft steei. 87. Standard test pieces of finished material shall have an ultimate strength of from 50,000 to 60,000 pounds per square inch; an elastic limit of one-half the ultimate strength; an elongation in 8 inches of not less than 25 per cent; and a reduction of area at fracture of not less than 50 per cent. Samples to bend cold 180 degrees flat on itself, without sign of fracture on the outside bent portion. soft-Medium 88. Standard test pieces of finished material shall have an steei. ultimate strength of from 55,000 to 65,000 pounds per square inch; elastic limit not less than one-half the ultimate strength; an elongation in 8 inches of not less than 25 per cent.; and a deduction of area at fracture of not less than 50 per cent. Samples to bend cold 180 degrees to a diameter equal to the thickness of the sample without crack or flaw on fhe outside of the bent portion. PAINTING. Painting. 89. All iron or steel framing and all corrugated iron, unless galvanized, shall have one coat of pure lead paint before leaving the shop; all surfaces in contact shall have one heavy 9 coat of pure lead paint before assembling, and all planed or turned surfaces shall be coated with white lead and tallow (66.) 90. Parts difficult of access after erectiion shall have two coats of pure lead paint at the shop. 91. After erection all the work except galvanized iron shall receive one coat of pure lead paint of such shade as the engineer or architect may select, and it shall be thoroughly and evenly applied. (72,95-) ERECTION. 92. The contractor will furnish all tools, derricks or staging Erection, and material of every description for the erection of the whole or such portions of the work as are included in the contract, and remove the same when the work is completed, leaving the prem- ises as free from rubbish or obstruction as when the erection was commenced. 93. The contractor shall assume all risks from storms or acci- dents to the work, unless caused by the negligence or interfer- ence of the owner or his employees; also all damage to persons and properties and casualties of every description, until the final acceptance of the completed structure. 94. The contractor shall comply with all ordinances or reg- ulations of the authorities having jurisdiction over the premises or abutting premises. 95. The erection is to be carried on subject to the approval and inspection of the engineer or architect, and it is to be com- pleted to his satisfaction and in full accordance with the contract. (72,91.) ^7\BRA OF THE UNIVtK3ITY OF 10 COEFFICIENTS FOR ROOF TRUSSES. s - ?rcx\V ~\vtxss. P25\/n*-i-i6 XP de 1.68 1. 80 1.95 0.25^24-36 XP fg 2.14 2.24 2.36 0.25^34-64 XP PRATT TRUSS, FOUR PANELS. ii I General Formula?. AAember ?z=3 11=4 n=$ Ba-Cb 2.70 3-35 4.04 xP +o.75v/;*2+ 4 La 2.25 3.00 3-75 0.75 n XP Lc 1.50 2.00 2.50 0.50 n xP ab I.OO I.OO I.OO + I.OO xP be 1.25 I.4I i. 60 -0.25v/ w 2 +l6 xP PRATT TRUSS, TWELVE PANELS. Member 0=3 n=4 = 5 General Formula?. Ba-Cb 9.92 12.30 14.81 +2. 75 x/^+? XP Dd 9.01 11.18 13.46 + 2.r > O v /;z2+4 XP Ef 8. n 10. 06 12.12 + 2.2 5x /^+^ XP Fh 7.21 8.94 10.77 + 2.00x/ w2+4 xP Gk 6.31 7.83 9.42 4-i-75x/*.+4 XP La 8.25 11.00 13-75 2.75/3 XP Lc 7.50 IO.OO 12.50 2.5077 XP Le 6.75 9.00 11.25 2.25 XP Lg 6.00 8.00 IO.OO 2.OOH XP Li 5-25 7.00 8.75 -1.75* XP LI 4.50 6.00 7.50 I.50H xP ab I.OO I.OO I.OO + 1.00 XP cd 1.50 1.50 1.50 + 1.50 xP ef 2.OO 2.OO 2.00 + 2.OO xP gh 2.50 2.50 2.50 + 2.50 xP ik 3-00 3.00 3 oo + 3-00 xP be 1.25 1.41 i. 60 o.25vV+i6 xP de i.68 1. 80 1.95 0.25^2+36 xP fg 2.14 2.24 2.36 -o 25v/,lH : 6^ xP hi 2.61 2.69 2.80 o.25vV-f IO o~ XP kl 3.09 3.16 3.25 o.25vV+i4 4 XP PRATT TRUSS, SIX PANELS. Member m *=4 *=S General Formulae. Ba-Cb 4.51 5-59 6.73 XP 4-i.25v/tf*4-4 Dd 3.61 -4-47 5-39 4-l.OOvV4-4 XP La 3.75 5.00 6.25 1,25 n XP Lc 3.00 4.00 5.00 i.oo n XP Le 2.25 3.00 3-75 0.75 n XP ab I.OO I.OO I.OO 4-1.00 XP cd 1.50 1.50 1,50 4-1.50 XP be t 1.25 1,41 1.60 -o.25v/^H[6 XP de i68 i. 80 1.95 O.25v/fl2_|- 36 xP PRATT TRUSS, TEN PANELS. Member n=, = 4 if =5 General Formulae. Ba-Cb 8.11 IO.O6 12.12 4-2.25^/^4^ XP Dd 7.21 8.94 10.77 4-2.oo^/fl2_f_4 XP Ef 6.31 7.83. 9.42 + t.7$,,/ T[3 2l/2-|-4 U DC 3-39 4.70 5-9* 4~7=L= (f* 2 -M) XP na+4 cd 1.50 2.00 2.50 T / -^ VX T) " r "y^.' Ld 2.25 3.00 375 j /^- v "O 74 7* A r STEEL COLUMN UNIT STRAINS. Q Q 12500 - 500 /-*-r n D /-7-r G D /-4-r n n *-r D D 3.0 IIOOO 7-6 8700 12.2 6400 16.8 4100 .2 10900 .8 8600 4 6300 17.0 4000 4 10800 8.0 8500 .6 6200 .2 3900 .6 10700 .2. &400 ,8 6100 4 3800 .8 10600 4 8300 13-0 6000 .6 3700 4.0 10500 .6 8200 .2 5900 .8 3600 .2 10400 .8 8100 4 5800 18.0 35 4 10300 9.0 8000 .6 5700 ,2 3400 .6 10200 .2 7900 .8 5600 4 33oo .8 IOIOO 4 7800 14.0 5500- .6 3200 5-o IOOOO .6 7700 .2 5400 .8 3100 .2 9900 ;3 7600 4 5300 19.0 3000 4 9800 ro.o 7500 .6 5200 2 2900 .6 9700 .2 7400 .8 5100 4 2800 .8 9600 4 7300 15.0 5000 .6 2700 6.0 9500 .$ 7200 .2 4900 .8 2600 .2 9400 '.8 '7100 .4 4800 20. o 2500 4 9300 li.o 700O .6 4700 ,2 2400 .6 9200 .2 6900 .8 4600 4 2300 8 9100 .4 6800 16.0 4500 .6 2200 7.0 9000 .6 6700 ; .2 4400 .8 2100 .2 8900 .8 6600 4 4300 4 8800 12. 6500 .6 4200 SHEARING AND BEARING VALUE OF RIVETS. Diam.ofRivet in inches. Area of Rivet. Single Shearat 10000 ft pr eq in Bearing val. of different thicknesses of plato at 20000 Ibs. per so. in. ( Diam. of Rivet X thickness of plate X 20000 Ibs. Frac- tion. . Deci- mal. \" iV' f" &" \" &" f" IOI6O IQ940 11720 H" ' fy W' 3." 1*3 // if i" H" -5625 .625 .6875 75 : 8125 .875 9375 .1963 -2485 .3068 .3712 ,-4418 .5185 .6013 .6903 1960 2480 3070 3710 4420 5l8o 6oiO 6900 2500 2810 3130 $440 3750 4070 4380 4690 3130 3520 3910 4290 4690 5080 5470 5850 3750 4210 4690 5160 5630 6090 6570 7030 4920 5470 6010 6560 7110 7660 8200 6880 7500 8I2C7 8750 9370 8440 9150 9840 10550 12890 INDEX. Acceptance, 72, 95. Imperfections, 73, 85. Sways, 41, 51, 52. Architect, 72, 91, 95. Span, 23, 27, 46. Anchors, 54. Joints, 24, 38, 65. Strain Sheet, i, 2, 72. Slate, 8. Bars, 13, 41, 63, 77,78, 79, Lacing, 60, 61, 62. Shapes, 13, 87, 88. 80, 81, 85, 87, 88. Lap, 28. Sag Ties, 42. Battens, 60. Laterals, 13, 20, 41. Secondary Members, 40, Bessemer Steel, 82. Lateral Connections,2o, 44, 45. Bearing, 18, 53, 65. 41. Sheeting, 8. Beams, 13. Lighting, 35, 36. Shearing, 17. Bending, 16, 19, 52,62,86, Loads, 5,6,7,8,9,10,11, 12 Screw, 63. Bed Plates, 53. Louvres, 34. Steel, 82, 83, 84, 85, 86, Boards, 6. 87, 88, Bolts, 21, 54. Machinery, n. Stiffeners, 25. Built Members, 69. Machine Shops,i 1,34,35. Splices, 24, 38, 65, 67. Main Members,39,43,44. Snow, 34. Clips, 31/47. Masonry, 3, 52, 53, 54. Snow Load, 5. Corrosion, 10. . y Mill Buildings, 10, n, Soft Steel, 86, 87. Columns, 14, 42, 44. 34, 35. Soft-Medium Steel, 86, Compression Members, 14, Minimum Loads, 10, 11. 88. 24, 43, 44, 45, 52, 58, 12. Sub-Struts, 44, 45. 59,60,61,65,66,69. Sulphur, 86. Completion, 95. Offsetting, 86. Skylights, 36. Combined Strains, 16. Open Hearth Steel, 82. Corrugated Iron, 8, 26,27, Test Pieces, 75, 83, 84. 28, 31, 32, 33-, 89, 91. Plate Iron. 87, 88. Tension Members, 13, Contractor, 72,93, 94. Painting, 66, 90, 91. 16,24, 37, 38, 3^, Planing, 65, 66, 89. 40, 41, 42, 57, 68. Damage, 92, 93, 94, 95, Plaster, 8. Timber, 22, 50. Drawings, i, 2, 72. Plate Girders, 13, 15,17, Tie Plates, 60. Decisions, 72. - 23, 24, 25. Tools, 92. Diagram, i, 2, 72. Pitch Roof, 4, 5-'6. Trusses, 9, 46. Dimensions, 3, 23. Pitch Rivets, 58, Turning, 66, 89. Drift Pins, 70, 71. Pins, 17, 18, 19. Process of Manuf 'g, 74, Upsets. 63. Elastic Limit, 76, 87, 88. 82. Unit Strains, 13, 14, 15, Erection/41, 51, 90, 91,92, Phosphorus, 86. X 6, 17, 18, 19, 20, _ 93, 94, 95- Punching, 55, 56, 57, 58. 21, 22, 59. Engineer, 72, 91, 92,93,94. Purlins, 8, 19, 22, 31,46, Valleys, 29. C1 95- 47,48,49,50. Variation in Weight, 64. Elongation, 77, 78, 87, 88, Purlin Spacing, 27, 48. Ventilation, 34, Purlin Clips, 31, 47- Falsework 92. Water, 29; 34- Framing, 89. Rafters, 43. Webs, 17, 24, 43, 62, Flanges, 13, 15, 24. Reaming, 56, 71. Weight Material, 64. Flashing, 29. Redress, 72. Weight of Trusses, 9. Field Connections, 21. Rivets, 17, 18,55, 56, 57, Wind, 6, 7. Finish Angle, 33. 58, 67, 68, 69. Windows, 35. Finished Surfaces, 65. Rivet Holes, 55, 56, 57, Wrought Iron, 73, 74, Foundations, 3, 52, 53, 54- 67,68. 75) 7 6,, 77 , 7 8, 79 , Foundries, 34. Ridges, 30, g o gi. Risks, 93. Girders, 13, 15, i 7 , 23, Roll Cap, 30. 24, 25. Rollers, 53* OF T.HE UN!VLK3ITY ;Jfj< -Covers 24" HlV **' ->l k- "Covers 4" p<- E8"before Corrugating >| K 30"before Corrugating"- j (] Note - Unsymmetrical sheets should fer o-- ;-H Louvre bars at panel points and 2.^4 for int. splice Corrug Louvres require an 8 sheet - plain Louvres 7i CORRUGATED IRON, LOUVRES, FLASHING &c. THIS BOOK IS DUE OK THE LAST DATE STAMPED BELOW AN INITIAL YC 13045 GENERAL LIBRARY- U.C. BERKELEY Boocmssss