SPECIFICATIONS Electric Railway Bridges. 1902 By C. S. Davis gpj&g. LIBRARY OT THE DIVERSITY of ILUNOk fc .... -.£**■ /. •• ■: " . ■ G 2cY H "it-J learning anb |Tabor. LIBRARY University of Illinois CLASS. BOOK. VOLUME. H Z.<5 Accession No. TABLE OF CONTENTS. ‘ GENERAL DESCRIPTION. Paragraphs. CLASSES i L. 20 2 - 3 L. 30 4 - 5 L. 40 6- 7 Recommendation TYPE 9 MATERIAL 10 CLEARANCE Single Track if Double Track . 12 Curves 13 CURVATURE 14 END BEAMS 15 STRINGER SPACING 16 GIRDER SPACING 17 FLOOR DECK 18 Rails iq Cross-Ties 20 Guard-Rails 21 PLANS 22 Stress Sheet 23 Working Drawings 24 Changes 25 Extras 26 5 t II PATENTS PROPOSAL Price Time Delays Damage LOADS DEAD LOAD LIVE LOAD L. 20 L. 30 L. 40 WIND LOADS Fixed Load Moving Load Additional Section Initial Stress Lateral Struts CENTRIFUGAL FORCE Additional Section Speed LONGITUDINAL STRESSES UNIT STRESSES, TENSION COMPRESSION SHEARING BEARING BENDING ALTERNATE STRESSES . . . COMBINED STRESSES TURNTABLE DETAILS VALUES OF © AND ~ 27 2S 29 3 ; J 31 3 J 33 34- 35 33 37 3^ 39 40 4 1 4' 2 43- 44 45 46 47 4S 49 50 5 1 5 1 51 5 1 5i 5 1 5 * 5 f Ill VALUES OF

2d miles per hour where d is the degree of curva- ture. (50) Due allowance shall be made for the stresses due to stopping the load upon the bridge. The coefficient of friction between the wheels and the rails shall be assumed at 0.20. Unit stresses 9— (51) Ail members shall be so proportioned that the stresses in pounds per square inch will not exceed those given by the following formula; / — IO — Wrought Iron. Soft Steel. TENSION Main members Counters and long: hangers Rolled beam flanges Built beam flanges Beam Hangers Bracing COMPRESSION Chords Posts Lateral struts SHEARING Web plates Shop rivets Field rivets Pins BEARING Shop rivets Field rivets Pins Rollers Masonry BENDING Pins f 2 1 8ooo{^| y_ 2 ) 7 °°°} 2 _ej f 2 ) 8000 {2 8ooo | 2 _-6 6ooo {^e} j 2 l 9°00 1 2^0 j {8000-35;} {^=0 f n{ 2 1 17000-30- 1 j -He j 1 nr 2 1 j 9 ooo-4o-|j 2 -=ej f 2 .1 5000 1 2 1^1 f 2 1 4000 { 2 — ej nr 2 1 s nr (9000-40- ^8000 35- 1 { 1 1000 5°;} j 2 — 9 j { 5OO° (2 _ 0 6000 '{A} f 2 5° 00 l^e S U-eJ r 2 1 i 2 °oo| 2 _ e | f 2 l i 2 ^ l 2 — e ) ioo°0( 2 _e | f 2 ) f 2 l l 2 — 0 ) 200 ( 2 — e \ Medium Steel. f 2 IOOOO |^zie 9000|^ f i 2 10000 IOOOO 8000 {A! LA ©I i 2 ^ I2000 (^re) ioooo-45;} {i=e| {9000-40}}!^} ■1 2 l rj l 12000—55- 2—0 J 2 1 55°o(^Hej 6000 iii! 1 1 2COO ' i 2 I 1 2-0 ( 350D-| ( 2 1 KJ 1 200 j f_i_l L 2 — © J I 5000 " f 2 ) (.2 e 3 ALTERNATE — n— STRESSES u se S.T-r^rJ ill place of j s- 2 ! in the above formulae Tension and + ^ /2-ej compression an d proportion for both compression and tension and use the larger area obtained. COMBINED STRESSES Compression and bending Tension and A = ! c + My | • t bending A - I T4. My ( ^ f r 2 i ‘ 1 ' TURNTABLE DETAILS Bearing: Cast i ro11 wheels on a cast iron track Bearing: Cast stee ^ wheels on a cast steel track Bearing: Hard steel rollers on a hard steel track Bearing: Phosphor-bronze discs on steel 400 D | 4°° D |*-e> 2500 D|. r i § | NOTE © =* y = r — 1 - f = A = C =» T- M - D - Dead load stress 4 - Total stress. Maximum Stress of the lesses kind — Maximum stress of the greater kind. Distance from centre of inertia to outer edge of the section in inches. Radius of gyration in inches. Length of member in inches. Unit stress from above formulae Required cross sectional area. • Total direct compression in pounds. Total direct tension in pounds. Bending moment in inch pounds. Diameter in inches. The same required areas will be obtained by dividing the live load stress by the first, factor of the above formulae and the dead load stress by two times the same factor and adding the two quotients as by the use of the above formulae. 12 — (52) Values of ® and © 2 1 2-e © 2 | '2-0 © 1 2 j 2-0 © 2 2-e j.000 1.005 .010 015 .020 i .0000 1 .0025 1 .0050 1 .0076 I.OIOI .200| ■205J .210) •2151 .220 I.IIII .4OO I.25OO I.II42 .405 I.2539 ‘1-1173 410 j 1.2579 1-12051.415! 1.2618 I. I236|.42o| I.2658 600 1 1 .4286 1 .800 ! 1 .6667 1 •605i1.4337i.805j1.6736! .610! 1.4388] .810T1. 68071 .6 1 5 1 1 .4440 i .8 1 5T 1 .6878 1 .620 1 1 .4493 1 .820 1 1 .6949 ; .025 1 1 .0127 j .225] 1 . 1267 1 .425 j 1 .26981 .6251 1 .4545 •030 1 1 .01 52 1 .230; 1 .12991 .4301 1 .27391 .6301 1 .4598 • 035 1 1.01781.235! 1.1332! .435' 1 .2780T.635 1 1 .4652 .0401 1.0204I.2401 1.1364I.4401 1.2820I.6401 1.4706 .82511.7021; .830IT.7094 1 - 835 j i- 7 I 67 i .840! 1.7241; •‘>15 1 -0230! -245! 1 • 1 3961-445 1 1 -2862 j .645 1 1 .4760! .84 5 ! 1 .73 16; 1.0501 1 .02561. 2 50! 1.1429I.4501 1.29031.650! 1.481 5I.8501 1. 739 1 1 i -055 1 1 -0283 1 .255 j 1 . 1461 ; .455J1 .2945L655 1 1 .4870*8551 1 .7467 i ,o6o| 1 .03091 .260] 1 . 14941 .4601 1 .29871 .66o| 1 .4925! . 8661 1 -7544 i -065 [ 1 .0336! .265 1 1 . 1 527 1 .465J1 .30291 .665 1 1 .4981 1 .865 ! 1 .7621 ; .070! 1.03631.270! 1.1561 L470J1. 3072 1 .670 j 1. 5038T.8701 1.76991 075 1 1 .0390J.275 1 1 . 1 594 1 - 475 ! I- 3 II 5 ! - 675 1 1 -50941 - 875 ! 1 - 7778 ; 080 j 1.04171.2801 1 .16281 .480] 1 .3 1 58T.680! 1 .5 1 5 1 ! .S80T 1 .7857: l-085i1.0444j.285J1.1662l.485l1.3201 j .685J1.5209J.8S5j 1 .7937! 1.090- 1. 0471 1.290 i_1.1696j.490f 1. 32451.6901 1.5267I.890I1.8018; : - 095 i i-O 499 j- 295 rr-i 730 l- 495 i 1-3289! .695 j x .5326! 895T1 .8100! .100I1.0526J.3001 1.1765I.5001 1.3333I.700I1.5385J.900I t.8i 82| 1 . 105 1 1 .0554J.305 1 1 . 1 799T.505 j 1 .3378! .705 j 1 .5444J.905 j 1.8265! .110l1.0582L310J1.1834l.510l1.3423l.710j 1. 5504I.910T1. 83491 1 1 5 i- 0610! . 3151 1.18691.515! 1.34681.71511.55641.915! 1.8433 . 1 20 1 1.0638|.320i 1. 1905 | -520| I.35 14|.720| 1. 5625 |.92o! T. 85 IQ: I 2 S I I.o 667 |. 32 S! I . I Q 40 1 . ^2 ^ i30il.0G95l.330l I. I976I.53O 1 4P 1.0753] .3401 1 .2048I.540 1 - 3559 ! - 7 2 5 l I - 5686 l. 925! 1. 86051 1 -3605 ! .730! 1 . 5748 1 .930 [ 1.8692] 135j1.0724J.335iL-2012l.535 1.36521.73511.5810!. 935! 1.8779 1 -3699 1 - 74 o! 1 . 5873 1 - 94 °T i . 8868 ; 1 45 : 1 .0782 1 .345 1 1 -2085 j . 545 Ji .3746 1 .745 1 1 .5936] .94 5 Jr .8957 ! .1501 1. 081 1 1 -35o| 1.2121 1 .5501 1.3793! .750I1.6000I.9501 1.9048! L1551 1. 08401.355! r .2 1 58 X-S 55 T 1 -3841 1 - 755 Ii-6064j.955l1.9139! . 160 1.0870I.360J1.2195J.5601 1.3889!. 760I i.6i29j.96oTi 9231] 1 . 165 1 1 .0899 j .365J 1 .2232 j .565 j 1 .3937 j .765 j 1 .61 94J.965T 1 .9324 j L170I1.0929J.370J1.2270J.570! i-.3986I.770l 1. 6260] .970] 1.9417! ' • 1 75 1 1 -°959 i -37.5ji .2308 1 - 575 1 1 -4035 1 -775 ! 1 -6327 1 .975 1 1 - 95 1 2 ! L.180! i. 09891.3801 T.2346I.580I1.4085J 7801 1. 6393 1.9801 1. 9608; . 185 1 1 . 1019 L385J1 .2384J.585T 1 .41 34I". 785 1 t .6461 1 .985T1 .9704: • T90! i. io5o|.39o[i. 2422 j . 590 f 1. 41841.790! 1. 6529!. 990T1. 9802! 1 . 195 1 1 . io8oj .395 J 1.2461 j .595! 1 .4235 1 .795 1 1 .6597 j .995 ! 1 .9901 !•'•••! !•■••] | — l j. ...| ji.ooj2.oooo : — !3— (53) Values of and 4> 2 _ 2 + cj> 2 2 +- $ 015 020 _2 2 +- cf> - 4 -. <$> 2 2 +■ $ 2 2 -t- 000 j 1. 0000 .200 j 0.909 1 400 j 0.8333!. 600 005 0.9975I.205I0.9070 .405 1 0.83 1 6 1.605 oro 0.9950! .210I0.09501 .41010.8299! .610 0.9926 1 .2 1 5 j 0.9030 j .4 1 5 1 0.8282 1 .6 1 5 o. 76931.800! 0.7 1 43 o.7678!.8o5|o.7i3t o. 76631.81010. 7118 0.7648!. 81510.7105 0.9901 1 .220 1 0.9009! .420^0.8265 1 .620(0.76341 .82010.709: 02510,98771.225 030i0.9852i.230 03510.9828). 235 040i0.9804j.240 04 S! 0 - 97 8 °i - 2 45 0.8989 1 .425 1 0.8248 1 .62 5 ! 0.7620 1 .825 1 0.7080 0.8969! .430] 0.823 1 1 .63010.7605 j .83010.7067 0.8949 ! .4351 0.82 14! .635 10.759 1 i .835 i 0.7055 O.8929! . 440|0. 8l97| .640!0.7576l .840I0.7O42 0.8909 1 .445 j 0.8 1 80 [ .645 1 o. 7562 j .84 5 ! 0.7030 °5°! 0.0756! .250I0.88891 .450I0.8164! .650J0.7548! .850)0.7018 D 55 j°. 9733 l - 255 1 0.8869). 455) 0.8 147). 655! 0.7533) .853! 0.7006 060 1 0.9709 1 . 260 1 0.88 50 1 .460 1 0.8 1 30 1 .660 ! 0.75 191 .860 1 0.6995 065 1 0.9686! .265 1 0.8830 1 .465 1 0.81 141 .665 1 0.7505 ! .865 1 0.698 r 070 j 0.9662 1 .270 1 0.88 1 o j .470 j 0.8098 1 .670 j 0.749 1 1 .870 ' 0.6969 •075 1 0-9639 1 .275H 0.879 1 1 .475)0.8081 1 -67510.7477' .875 1 0.6957 .080 [ 0.96 1 6| .280 j 0.8772 1 .480 1 0.8065 J .680 ) 0.7463 i .880 1 0.694 5 •085 1 0.9593 1 -285 i 0.8753 [ .485 10.8049 1 -685 1 0.7449 ! .885 ! 0.6933 •090lo.9570l.290lo.8734l.490lo.8033l.690lo.7435j.890io.692r • O 95 l 0 - 9547 l- 2 95 |o- 87 1 5 [- 49 sio- 8 oi 6 | .695 10.7422). 895)0.6909 . 1 00 1 0.95 241 . 300 1 0.8696 . 500 1 0.8000 1 . 700 ! o. 7403 1 .900 ! 06897 •105 io.9S02 ) .305 1 0.8677 L 505 '0.7984! .705 10.73941 .905)0.6885 • t 10)0.9480) .310I0.86581. 5 10)0.79681. 710)0. 7380 1 . 9100 6873 • II 5 l 0 - 94 S 7 l- 3 i 5 l 0 - 8639 |. 5 i 5 lo. 7952 ). 7 i 5 lo. 7367 l . 9 i 5 ! o .6863 .■I20lo.9434j.320lo.8621 1.520)0.79371. 720)0.73531.920)0.6850 . 125 |o.94i2|.3 2 5|o.86o2|. 525 10.7921 1.72510. 734 o ! . 925 ! o. 6838 •'30I0.93901. 330j0.8584l.53ol0.7905). 73010.73271.93010 6826 ■135I0.9368I.235I0.85661. 535 10.7890). 735)0.7313). 935)0.6814 .140I0.93461. 340 t0.8548l.540jo.7874!. 740)0.7300) .940I0.6803 •t 45 i 0 - 93 2 4 l- 345 l°- 85 2 9 !- 545 .|o- 7859 ! •745)0.7286). 945)0.6792 .150I0.9303I.350I0.8511 1 . 550)0.7843!. 750I0.7273I.9500.6780 - 1 55 I°- 9 2 8 i 1 .355 jo.8493 1 .555 10.782&I .755 10.7260] .955)0.6769 . 160)0.9259 1.360I0.8475I.5601 0.78 1 3 1. 760)0.2747). 9 6 o'o. 675~ . 1 65 ) 0.9238 1 .365 1 0.8457 1 . 565 1 o. 7798 1 .765 1 o. 7234 i .965 1 0.6746 . 170)0.92171. 370I0.8439I.570I0.7782]. 770)0.7221 !.970 l o.6734 •• 1 75 ! 0-9196 1 - 375 1 0.842 1 1.57510.77671. 775)0.72081. 975'o.672 5 . [80)0.9175!. 38010.8403!. 58010.7752). 780)0.71951. 980^.671 2 • ' 85 I 0 . 9 I S4I.385I0.8386!. 585)0.7737!. 785|o.7I82i.985 , 0.6701 . 190)0.91331. 39o|o.8368l.59o|o.7722!.79o l o.7i6g , .99o ! o 6690 • ' 95 1 0.9 1 1 2 1 - 3951 0-835 1 !• 595 1 07708 1 .795 ) o. 7 1 56 1 .795 1 0.6678 1 r. 00 '0.6667 H— (54) Shearing and Bearing value of Rivets in pounds with © = O. Diameter | Iron Rivets Steel Rivets i Shop | Field Shop | Field 1 1 f in. Rivet. 1 Single Shear > 1534 | 1227 | f in. Rivet. J in. Bearing | 1562 1250 1841 ! 1534 ! 1875 ! 1562 1 | f in. Rivet. | f in. Rivet. I f in. Rivet, i # in. Rivet. 5-16 in. Bearing § in. Bearing. . . 7-16 in. Bearing Double Shear. . ! J in. Rivet. | f in. Rivet. ! j in. Rivet, j f in. Rivet. I | in. Rivet, f in. Rive' . ! | in. Rivet, j f in. Rivet. i i. in. I f in. I i in- I J in. I £ in. in, ! i in. I i in. I £ in. ! I in. Rivet. Rivet. Rivet. Rivet. Rivet. Rivet. Rivet. Rivet. Rivet. Rivet. | Single Shear. | J in. Bearing, ! 5-16 in. Bearing | § in Bearing. . . | 7-16 in. Bearing | \ in. Bearing. . . I 9-16 in. Bearing [ Double Shear. . | Single Shear. . . ! I in. Bearing. . . ! 5-16 in. Bearing I | in. Bearing. . . I 7-t 6 in. Bearing I 4 in. Bearing. . . I q-t 6 in. Bearing I 5 in. Bearing. . . : it - 16 in. Bearing | Double Shear. . . • I 1953 ! 1562 ! 2344 I 1953 ! ■ ! 2 344 I 1875 | 2812 j 2344 1 . ! 2734 j 2187 1 3281 1 2734 ; . I 3068 I 2454 | 3682 j 3068 | . | 2209 | 1767 | 2651 ! 2209 i . 1 1875 1 t 500 1 2250 i 1875 1 1 2344 I T875 1 2812 1 2344 ] . ! 2812 | 2250 | 3375 ! 2812 i . I 3281 ! 2625 | 3937 1 3281 ; . f 3750 I 3000 1 4500 ! 3750 | • I 4219 I 3375 I 5062 ! 4219 ! • ! 4418 1 3534 1 5302 ! 4418 ; ! 3006 | 2405 | 3608 | 2187 I T 75° I 2625 j 2734 1 2187 | 3281 | 3281 ! 2625 | 3937 I 3828 | 3062 | 4593 v I 4375 I 35oo I 5250 I 4375 ! j 4922 | 3937.I 5906 ! 4922 | | 5469 ! 4-375 ! 6562 ! 5469 i I 6015 ! 4812 | 7218 l 6015 ( | 6012 I 4810 I 7216 ! 6012 ! 3006 j 2187 ! 2734 I 3281 ! 3828 i DETAILS Of DESIGN Limiiing Sizes Thickness Angles Bars Columns Flanges Pins End Bearings Lead Anchors Pin Bearings — 15 — (55) No metal less ‘than 5-16 of an inch thick shall be used except for fillers. Web plates in stringers beams and girders shall not be less than 3-8 of an inch thick. (56) No angle weighing less than 5 pounds per lineal foot shall be used. (57) No bar having an area of less than 1 square inch shad be used. (58) The ratio of the length of any column to its least radius of gyration shall not exceed 125 for main members and 150 for lateral struts. (59) The thickness of plates in columns shall not be less than 1-40 of the distance between supports in a direction at right angles to the line of stress and not less than 1-16 of the distance between supports or rivets in the line of stress. (60) Beams and girders having a length greater than 16 times the width of the flange shall be braced horizontally. (61) The diameter of no pin shall be less than 3-4 of the width of the widest bar attached to the same. (62) Sheet lead not less than 1-8. of an inch in thickness, shall be interposed between ad bearing plates and masonry. (63) All bearings shall be thoroughly and effi- ciency anchored to the masonry by means of bolts, not less than 1 1-4 inches in diameter, set at least 12 inches into the masonry with neat Portland cement mortar. (64) To insure a more even bearing on the ma- sonry, spans of 80 feet or more in length shall have pin end bearings. Cast steel pedestals will be preferred for plate girder spans. — 16— Sliding Ends Roller Ends Pin Plate Camber Trusses (65) Spans less than 75 feet in length may have sliding plates at one end of the span to allow for ex- pansion and contraction due to a change in temperature of 150 degrees Fahrenheit. Each bearing shall consist of two plates, an upper or shoe plate and a lower or ma sonry plate. Both shoe and masonry plates shall be planed, and the joint between the two plates shall be planed with tongue and groove for both fixed and sliding ends of the span. The finished thickness of the plates shall' not be less than 3- 4 of an inch. The anchor bolt holes in the shoe plates on the sliding end must be slotted to allow for expansion and contraction. (66) One end of all spans of 75 feet or more in length shall have roller end bearings to permit free ex- pansion and contraction, due to a change in temperature of 150 degrees Fahrenheit. (67) The rollers shall not be less than 3 inches in diameter, shall be turned with a groove at the center, and shall travel between shoe and masonry plates, each of which shall be planed with a tongue. (68) All rollers of a single bearing shall he joined by spacing bars at their ends. All roller bearings shall have guards to protect them from dirt and shall be made accessible for cleaning. (69) For heavy or long spans, segmental rollers and a masonry plate, built up of railroad rails, and a plate will be preferred. (70) On piers, the masonry plate shall be con- tinuous, extending under both bearings of contiguous spans. (71) All trusses shall have just sufficient camber so that under a full load the truss will come to a level - 17 - Plate Girders Framing Out Rivets Net Section Rolled Beams Built Beams Flanges line. This will be accomplished by shortening each ten- sion member and lengthening each compression mem- ber by an amount equal to the change in length of that member under full load. (72) Plate girders shall be given a camber equal to one one-thousandth of the span. (73) One-half of the camber shall be framed out in the beams and stringers, and the ther half in the ties. (74) Rivets shall generally be 3-4 and 7-8 of an inch in diameter, they shall be spaced at least 3 diameters apart and except in lacing bars their centers shall not be nearer the edge of any member through which they pass than 1 1-4 inches. No rivet shall have a grip exceeding five times its diameter. (75) The net section of any tension member or flange shall be determined by a plane cutting the member square across at any point. The greatest number of rivet holes which can be cut by the plane or whose centers come within one inch of the plane, is the number to be deducted from the gross sectio . (76) Rolled Beams shall be proportioned for bending stresses in accordance with their moments of inertia. (77) Built beams, used for stringers, floor beams or girders, shall be proportioned in accordance with the fol- lowing assumptions : (78) It shall be assumed that the bending stresses are resisted entirely by the flange section. No part of the web plate shall be assumed as effective for flange section. (79) Flanges shall be proportioned from the — 1 8— Web Plate tension stresses, and the compression flange shall have the same gross section as the tension flange. (80) It shall be assumed that all the shear is car- ried by the web plate. Effective Depth (81) The effective depth shall be the distance be- tween centers of gravity of the flanges except when this exceeds the distance out to out of flange angles. In no case shall the effective depth be taken at more than the distance out to out of flange angles. Flange Splices (82) So far as possible, splices in the flanges shall be avoided. When splices become necessary, all joints must be fully spliced, all abutting surfaces must be machine finished and must be brought into perfect con- tact in assembling. In the tension flanges, sufficient section must be provided in the splices to make up for all lost section in the member spliced. Web Splices (83) Splices in web plates shall be made at points where stiffeners occur, and shall be made with a plate on each side of the web, wide enough to take two rows of rivets on each side of the splice. The splice plates shall not be thinner than the web itself. Stiffeners (84) When the unit shear on the web plate ex- ceeds that allowed by the formula o noh S=i 1000 — ~y stiffeners shall be used. Note):- — S *= Allowed shear in pounds per square inch. h = Unsupported height of web in inches. t = Thickness of web in inches. See curves in appendix. - 19 — (85) Stiffeners shall consist of a pair of angles, one on each side of the web and they shall be spaced at intervals, about equal to the depth of the girder. (86) The size of the stiffener angles shall be as follows, depending upon the width of the horizontal ieg of flange angles : For an 8 inch leg use 6x3 1-2 x 3-8 angles. For an 7 inch leg use 6x3 1-2 x 3-8 angless. For a 6 inch leg use 5x3 1-2 x 3-8 angles. For a 5 inch leg use 4 x 3 x 3-8 angles. For a 4 inch leg use 3 x 3 x 3-8 angle. (87) A pair of stiffeners shall be used over each end of each end bearing, and when pin bearings are used, there shall be an additional pair over the center of each bearing. (88) Fillers, equal in thickness to the flange angles, shall be used under all stiffeners, except at splice po’nts where the splice plates serve for fillers. (89) When side plates are used under the flange angles, the fillers shall be of the same thickness as the side plates, and the stiffeners may be crimped over the flange angles. (90) The pitch of rivets uniting the flange angles to the web plate shall not exceed that given by the for- mula : p = r d -4- s where p = Pitch of rivets r = Value of one rivet d = Distance between rivet lines s = Shear at the point under consideration. -30 (91) The pitch of rivets between stiffeners shall be uniform, and shall be determined from the shear at the siffener nearer the end of the girder, but in no case shall the pitch of rivets in each gauge line exceed 9 inches. k rac ‘ n £ (92) Deck girders less than 30 feet in length, shall be braced in the plane of the top flanges, and shall have cross frames at ends and at intermediate pouits. Deck girders 30 feet or more in length shall have top and bottom bracing, and cross frames at the ends and at intermediate points. The bracing shall generally take the form of a Warren truss, the diagonal members in the top system being made of two angles back to back, and in the bottom system, of a single angle. This di- agonals in the cross frames shall consist of two angles in each direction, the top and bottom horizontals of two angles for the end frames, and of one or two angles for the intermediate frames as may be required. All angles shall be connected at their ends so as to develope their full strength. (93) Through girders shall have one set of ad- justable, horizontal, lateral bracing, generally using the floor beams for struts. The floor beams shall be at- tached to the main girders through gusset plates ex- tending the full depth of the girders. When the gus- set plate extends more than 96 times its thickness above or below the beam, there shall be two 3x2 1-2 inch angles riveted to its edge. End Finish (94) All through girders shall have their upper corners rounded and the first flange plate shall extend down to the bottom of the girder. (95) The ends of all deck girders shall be covered Ends Faced Pin-connected Bridges Compression Members Battens Lattice with a p!ate riveted to the end stiffener angles, and in addition, there shall be corner cover plate riveted over each upper corner of the girder. (96) When the detail will permit, the ends of all stringers and floor beams shall be faced and extra ma- terial must be provided in the end angles to allow foi planing. (97) End post and top chord sections shall gen- erally consist of two rolled or built channels, joined on their upper flanges by a cover plate, and on their lower flanges by batten plates near the ends and diagonal lattice bars between the battens. (98) Intermediate posts shall generally consist of two rolled or built channels joined on both flanges by battens near the ends, and diagonal lattice bars be- tween the battens. (99) The length of the batten plate shall not be less than the greatest width of the member and. its thickness shall not be less than T-40 of its un- supported width. No batten shall have less than three rivets along each edge. (100) Lattice bars shall have a width of at least three diameters of the rivet and a thickness of at least 1-50 of the unsupported length. The spacing of the bars shall be such that the angle be- tween the bar and the center line of the section shall not be less than 60 degrees, for single lattice and 45 degrees for double lattice and the distance between rivets in either channel flange shall not exceed 60 times the thickness of the flange. Double lattice bars shall have a rivet at each inter- section. On large or wide sections, 3x2 inch an- gles shall be used instead of bars for lattice. 22 Ri ve ling; Pin-plates Pin-holes Splices Eyebars ( idi ) At each end of any compression mem- ber for a distance equal to twice its width the pitch of the rivets shall not exceed four diameters of the rivet and throughout the remaining portion of the member the pitch shall net exceed 6 inches or 1 6 times the thickness of the thinnest plate or angle. (102) Where necessary pin holes shall be re- inforced by pin plates. At points where the stress is transmitted entirely to the pin, the first pin plate shall extend back from the pin far enough to over- lap the batten plate by at least 6 inches. (103) When computing the necessary num- ber of rivets for the pin plate, the bearing per square inch between the pin and pin plate shall be assumed the same as between the pin and main member. (104) Pin holes shall be placed with ref- erence to the center of moments of the section and they shall be placed enough below that center to balance the bending moment due to the weight of the member. (105) Splices in the top chord shall gener- ally be made a short distance from the pin point and all splices shall be equiped with splice plates and cover plates to hold the members truly in po- sition. (106) The main diagonal and bottom chord members shall be made of die forged eyebars, con- structed in such a way that when tested to destruction they will break in the main body of the bar rather than in the head. Stiffened Sections Adjustable Members Stringers •Beams Bracing Top Struts Knees Cross Bracing Portals — 23 — (107) The first two panels of bottom chord at each end of the span and the hip verticals or long sus- penders shall be stiffened. These members may be laced eyebars. (108) All counters and lateral rods shall be ad- justable by means of open turnbuck'es or devices. The threaded ends of all rods must be upset. The ends of all rods attached to pins shall have loop eyes with the distance from the back of the pin to the apex of the loop not less than three diameters of the pin. Only iron bars may have loop eyes. (109) The stringers shall preferably be framed in between the floor beams ; if placed on top they shall have a cross frame at each end. ( 1 10) The floor beams shall be built in between the posts of the main trusses and shall be connected to the same through gussets extending at least 3 feet above the top of the beam. (hi) All pin connected bridges shall have ad- justable bracing in the planes of the top and bottom chords and as near as practicable to the pin center lines. ( 1 12) The top struts shall generally be made of four angles laced the full depth of the ch?rd. (113) When the distance from rail to top strut does not exceed 25 feet, knee braces shall be used connecting the top struts to the vertical posts of the main trusses. ( 1 14) When the distance from rail to top strut exceeds 25 feet, sub-struts and cross-bracing shall be used instead of knee braces. ( 1 15) The end posts shall be connected by portal struts, so designed as to effectively transmit 24 - Viaducts or Trestles Type Bents Towers Rocker Batter Bearings Anchorage Bracing the wind stresses from the top lateral system to the bridge seat. Portals shall be as deep as the specified clearance will permit and brackets usual- ly curved, shall be used connecting the bottom flange of the portal strut to the end posts. (116) Viaducts shall generally consist of plate or open web riveted girders, supported by bents and towers. ( 1 17) A bent consists of a pair of columns braced transversely. (118) A tower consists of two bents braced longitudinally. (119) When a bent is used separately it shall be designed as a rocker and shall have pin ends at top and bottom. (120) Each column in a bent shall have a batter of not less than one horizontally to six vertically. (121) Provision shall be made at the foot of each bent for expansion and contraction due to changes in temperature of 150 degrees Fahrenheit. All sliding surfaces shall be planed and anchor bolt holes slotted (122) All bents and towers shall be anchored to the foundations in such a way as to be safe against overturning whether loaded, unloaded or loaded with empty cars. (123) When a viaduct is located on a curve, the effects of centrifugal force must be considered: in addi- tion to the wind loads. (124) Transversely all bents shall be braced with angles against all efifects of wind and centrifugal force. Longitudinally all towers shall be braced with Swing Bridges Floor System Trusses Turntable Disc Center Roller Center - 25 - angles or channels against the effects of stopping a train on the viaduct. Transverse struts shall be used at the bottom of a* 1 bents and longitudinal struts at the bot- tom of all towers strong enough to slide the columns when changes in temperature occur. (125) The floor system of swing bridges shall be designed the same as for fixed spans. (126) Wffh the bridge closed, the trusses shall be designed under the same unit stresses as for fixed spans, but with the bridge open the dead load unit stresses shad not exceed three-quarters of the dead load unit stresses for fixed spans. (127) The turntable may be center bearing, rim bearing or a combination of the two. If the combina- tion table is used the supporting girders shall be so ar- ranged that some definite and known portion of the load will be carried to the center. (128) When a disc center is used there shall be three discs, the upper and lower of hard steel and the center of phosphor bronze, and so arrang- ed that all sliding will occur between the steel and phosphor bronze discs. The discs shall have oil grooves and the center shall be so arranged that the discs may be kept flooded with oil. (129) When a roller center is used the roll- ers shall be turned truly conical and shall be pro- vided with a band to ho’d them in position. All rollers shall be of hard steel and will travel be- tween tracks of hard steel, planed to a true bevel to fit the rollers. The center shall be so arranged that the rollers may be kept flooded with oil. — 26 — f&m Bearing; LatdfcS End Lifts (130) When a rim bearing table is used, the load shall be conveyed by means of a circu ar drum to a set of cast steel wheels turned truly conical which travel between two steel tracks, one above attached to the drum and one below attached to the foundation. The tracks shall be planed circular and to a true bevel to fit the wheels. (131) The bottom track, wheels afid drum shall be connected to an iron casting at the center of the -table in order to keep all properly centered. The drum shall be connected by means of radial struts to a hub which is free to rotate about the center casting. The wheels shall be connected by means of spider rods to another similar hub. (132) There shall be two circular bands to keep the wheels properly spaced one inside and the other outside the wheels. The outer band shall be made in short sections so arranged that any wheel may be easily removed and replaced without disturbing the others. Each spider rod shall extend through a wheel and both bands and shall be provided with nuts and washers making it possible to adjust the conical 1 wheels to a shorter or longer radius. (133) Both ends of the bridge shall be provided with strong latches arranged to close automatically and to be opened from the tender’s house. (134) End lifts shall be provided for raising both ends of the bridge by an amount sufficient to pre- vent the lifting of either- end clear from its seat under any position of the load. They shall be so arranged that they may be operated from the tender’s house. Kail Lifts End Signals Machinery Cables Motors Material Tender’s House —27— (135) Both ends of the bridge shall be equipped with suitable rail lifts arranged to be operated from the tender’s house. ( 136) At each shore end of the bridge there shall be an automatic signal so> arranged that the bridge cannot be opened without setting the signal to the position of danger. ( 1 37 ) Under this head shall be included all mo- tors, cables, wires, switches, controllers, lightening ar- resters. electric heaters, gears, shafting, rack and such other equipment as is necessary to make a complete and perfect plant for the operation of the bridge by both hand and electric power. (138) The necessary sub-marine cables shall be furnished by the Contractor for the superstruc- ture, but shall be put in place by the Contractor for the substructure. (139) The motor for turning the bridge shall be of sufficient capacity to turn the bridge through a quadrant in one minute, starting from rest and ending at rest. ( 140) The motors for operating the end lifts, rail lifts and end signals may be placed at the ends of the bridge. (141) All shafting shall be medium steel, all pinions, gears, rack and shaft bearings shall be cast iron or cast steel. All shaft bearings shall be babbitted. (142) A tender’s house of neat design shall be provided at the center of the bridge, preferably over the track, in which all controllers, switches, lightening arresters, heaters and other electric equipment shall be — 2g— Shop work Fifst Class Straightening Punching Reaming Drilling Riveting placed. When necessary a stairway shail he provided for the tender’s house. (143) All shop work shall he first class in every par- ticular. (144) When necessary all material shall be straight- ened before being laid ofb. After punching and before as- sembling all material shall be carefullv straightened and freed from all twists and buckles. A'l web plates must be free from buckles. ( t45 ) All straightening shall be done in presses of between rolls. Hammering will not be allowed. (146) All punched holes shall be made with a punch one-eighth of an "nch smaller in diameter than the rivet. The die shall not be more than one-sixteenth of an inch greater in diameter than the punch. (147) After punching and assembling all punched holes shall be reamed to a diameter not more than one-six teenth of an inch greater than the diameter of the cold rivet. After reaming all holes shall be smooth, showing that nietal has everywhere been removed around the hole. (147) When any metal is too tlr’ck for successful punching, all holes shall be drilled. All rivet holes in eve- bars shall be drilled and all pin holes shall be drilled or bored. (149) All shop rivets so far as possible shall be driven with a machine capable of holding the pressure after the rivet is driven. All rivets shall be driven tight and upset so as to completely fill the hole. No calking or cupping will be allowed. Rivets of the same size shall have the sqme size heads and the heads must be concentric with the rivet. All loose or poor rivets must be cut out and replaced. — 29 - Facing Fitting Planing Pin Holes Lathe Work Eye-bars Material Heads (150) The ends of all beams and stringers, when built in. shall be faced square and true to length. ( 1 5 1 ) Abutting ends of all compression members shall be faced in a machine so that their ends will be in per- fect contact when in pi ace in the bridge. (152) The ends of all stiffenerj shall be trimmed to fit tight against the flange angles and all fillers under the stiffeners shall be made to fit tight against the edges of the flange angles. (153) All abutting ends of web plates for plate gird- ers shall be planed. (154) The edges of all sheared plates shall be planed. (155) All shoe and masonry plates shall be planed so that the two faces of each plate are truly parallel. (156) Pin holes in riveted members shall be bored truly parallel to each other and at right angles to the axis of the member. (157) Pin holes in eyebars must be in the axis of the bar, in the center of the heads and at right angles to the planes of the flat surfaces. When all the bars of the same member are piled together, the pins shall pass through both ends of all bars without driving. (158) The diameter of the pin hole shall not exceed that of the pin by more than 1-50 of an inch except for pins over 4 inches in diameter when this excess shall not exceed 1-32 of an inch. (159) All pins and rollers shall be turned smooth and true to £ize. (160) All eyebars shall be made from bars of full section and free from folds, cracks, or other defects. (161) - The heads shall be made by upsetting and forging the bars. No head shall be more than one-six- Annealing Adjustable Rods Loop Eyes Upsettirg Annealing Painting Cleaning: Before Assembling inaccessible Parts Machined Surfac«s So— teenth of an inch thicker than the body of the bar. All heads shall be so proportioned and made that the bars will break in the body of the original bar and not in the head or neck. (162) After the heads are Completed the bars shall be annealed by being heated to a bright red heat throughout their entire length and then allowed to cool slowly. (163) The ends of all rods attached to pins shall have loop eyes formed by bending the bar around a pm and weMing the end to the main body of the bar. All loop eyes shall have holes bored to fit the pin. Only iron bars may have loop eyes. (164) The ends of all rods that take nuts, turn- buckles of devices shall have their ends enlarged by upsetting the bar. The cross-sectional area of the upset end at the root of the thread shall be at least 10 per cent, greater than the original area of the bar and under test to destruction the bar must break in the » main body and not in the upset end. (165) Steel bars with upset ends shall be an- nealed the same as eyebars. See paragraph 162. (166) All material shall be thoroughly cleaned from dirt rust and Scale before any oil or paint is ap-. plied. Wire brushes and steel scrapers shall be used when necessary. (167) All surfaces Coming in contact shall have one coat of red lead paint before assembling. (168) All parts not accessible after erection shail have two coats of red lead paint. (169) All machine finished surfaces shall have a coat of white lead and tallow before shipment. Other Parts — 3 1 — (170) All other parts shall have one coat of boil- ed linseed oil before shipment. Application (171) No oil or paint shall be applied in wet or freezing weather, or when the metal is not dry, and no coat shall be applied until the one before is thor- oughly dried. No material shall be painted until after it has been examined and accepted by the inspector. (172) All oil and paint shall be applied with good thick brushes (round preferred) with elastic bristles, by skilled painters and shall be thoroughly brushed out and worked into all open spaces and so applied as to completely cover the surface. (173) All oil, when applied, shall be heated to a temperature of from 150 to 200 degrees Fahrenheit. (174) All red lead paint shall be kept well stirred while it is being used. FIELD WORK Ready for Rails Floor Deck Falsework Interrupting Traffic (175) Unless otherwise specified all bridges shall be erected by the Contractor ready for the rails. (176) All rail.;, splices and fastenings for the same shall be furnished and put in place by the "Railway Company ; all ties and guard-rails shall be furnished, delivered at the bridge site, by the Railway Company, but will be put in place by the Contractor, all floor deck bolts, washers, nut locks, etc., being furnished by the Contractor. See paragraphs 18 to 21 inclusive. (177) All falsework timber, bolts, etc., shall be fur- nished and put in place by the Contractor and shall be re- moved by him after completion of the work. (178) When a bridge is being erected on a line al- ready in operation, the work shall be done without inter- rupting traffic, except as arrangements are made for such interruption. Renewal Anchorage Watchmen Laws Risks Reaming Riveting turned Bolts hlot Nuts Fainting Cleaning Rivet Heads (179) In case of a renewal the Contractor shall take down the old bridge and pile the same on the bank or load it on cars as may be directed. (180) The Contractor shall drill all the necessary ari a chor bolt holes in the masonry, and shall set the bolts in place, fastening the same with neat Portland cement mortar. (181) When necessary the Contractor shall provide Watchmen and other safeguards during erection. (182) The Contractor shall comply with all laws and ordinances whenever there are any applicable to the work it! execution. (183) The Contractor shall assume all risks of acci- dents or from floods or other causes until the final comple- tion of the work. / (184) When assembling the Work in the field, any inaccuracies in the rivet holes must be corrected by reaming, drifting will not be allowed. Drift pins may only be used to bring the pieces together. (185) All rivets must have full heads, concentric with the rivet, of a uniform size for the same size of rivet and must be driven so as to Completely fill the holes. Loose or poor rivets must be cut out and replaced. (186) Where it is impossible to drive rivets in the field, turned bolts may be ttSed provided they are turned to a driving fit. (187) Pilot nuts shall be used on pins to protect the threads when the pins are being driven. (188) Before applying the field coats of paint, all members shall be cleaned from all blisters, loose paint and dirt. (189) After erection and before applying the First Coat Second Coat Application QUALITY OF MATERIAL Wrought steel Process Finish Variation — 33 — finishing coats all heads of field rivets shall he painted with the same material as used for the first field coat. (190) After erection all accessible parts shall re- ceive one coat of “Red Lead Metal Preservative.” (191) After the “Red Lead Metal Preservative” is thoroughly dry all accessible parts shall receive a second field coat which shall be a high grade graphite or carbon paint. (192) No paint shall be applied in wet or freez- ing weather, or when the metal is not dry. All paint shall be applied with good thick brushes (round pre- ferred) having elastic bristles and by skilled painters. All paint must be well rubbed onto the surface and worked into all open spaces and so applied as to com* pletelty cover the surface. (193) All wrought steel shall be made by the Open hearth process. (194) The finished product shall be true to size and shape and free from imperfections such as cracks or roughness. When two or more universal mill plates of the same width come together in the finished work they must be of uniform width and their edges must not be beveled. (195) No greater variation than 2j per cent, shall be allowed between the estimated and actual weight of any piece of material except for wide plates where the actual weight may exceed the estimated weights by the amounts given in the following table : Phosphorus Test Pieces Ultimate Strength — 34 — Thickness Width of Plate in Inches. in Inches. 48 to 75 I _75 to 100. | Ovrer 100. IH [ 10 per cent. 14 per cent. | 18 per cent. 5 -i 6 l 8 per cent. | 12 per cent. | 16 per cent. ■ 3-8 1 7 per cent, i 10 per cent. 13 percent. 7-16 1 6 per cent. 9 per cent. 10 per cent. 1-2 | 5 per cent. | 7 per cent. 9 per cent. 9-16 1 4 \ per cent, j 64 per cent, j 84 per cent. 5-8 | 4 per cent. 1 6 per cent. 8 per cent. Over 5-8 | 3-|- per cent. | 5 per cent. 64 per cent. (196) The amount of phosphorus shall not ex- ceed .08 per cent, in steel made in an acid furnace and .04 per cent, in steel made in a basic furnace. (197) The properties of steel shall be determin- ed from test prices cut from the finished product, rep- resenting each melt. (198) The test pieces, about 12 inches long, shall be planed or turned to a uniform area of not less than 4 of a square inch for a length of 10 inches. (199) Pieces representing annealed bars may be annealed before testing. (200) When a melt is rolled into several varie- ties of material a test piece shall be taken from each va- riety. (201) The ultimate strength of the several grades of steel, as determined from the test pieces, shall be within the following limits : Hard steel, 70,000 to 78.000 lbs. per square inch. Medium steel 62,000 to 70,000 lbs per square inch. Soft steel, 54,000 to 62,000 lbs. per square inch. Rivet steel, 50,000 to 58,000 lbs. per square inch. Elastic Limit Elongation Reduction of area Fracture Bending Hard Steel Medium Steel Soft and Rivet Steel Drifting — 35 — (20 2) The elastic limit shall not be less than 55 per cent, of the ultimate strength. (203) The elongation in 8 inches shall not be less than — - 18 per cent, for hard steel. 22 per cent, for medium steeh 24 per cent, for soft steel. 26 per cent, for rivet steel. (204) The reduction of area at the point of frac- ture shall not be less than — 35 per cent, for hard steel. 40 per cent, for medium steel. 45 per cent, for soft steel. 48 per cent, for rivet steel. (205) The entire fracture must be silky. (206) A piece of each test piece shall be bent cold 180 degrees. (207) No specimen from hard steel shall show any signs of cracks until the diameter of the circle around which the bar is bent becomes less than 3 times the thickness of the specimen. (208) No specimen from medium steel shall show any signs of cracks until the diameter of the circle around which the bar is bent becomes less than the thickness of the specimen. (209) Each specimen from soft or rivet steel shall bend 180 degrees and close upon itself with- out sign of crack or flow on the convex surface. (210) The ductility of medium and soft steel shall be such that a punched hole, the center of which is not more than i\ inches from the sheared or rolled edge of any piece may be enlarged by drifting to a diam- Duplicate Tests Marking Eyebar Tests -36- eter 50 per cent, greater than the original hole without cracking the specimen at any point. (21 1 ) Duplicate tests may be made when the sample fulfills all but one of the requirements. If the second test and the average of the two tests meet all the requirements, the melt may be accepted. (212) All material shall be plainly stamped with a number identifying the melt. (213) The eyebars required for tests and those for the structure shall be made at one time. The test bars to be selected by the Inspector, must be fair aver- age specimens of those which would be classed as good bars acceptable for the work. No bar which is known to be defective shall be selected for testing. (214) These bars will be required to develope a minimum stretch of 14 per cent, before breaking if of soft steel and 12 per cent, if of medium steel. The elongation to be measured on a gauged length of 10 feet including the fracture. (215) If medium steel is used the bars shall show an ultimate strength of not less than 62,000 — 9.000 (area — perimeter) and if soft steel not less than 54,000 — 8,000 (area perimeter). The elastic limit in all cases shall not be less than 55 per cent, of the ultimate strength. (216) In general bars will be required to break in the body. When a bar breaks in the head but de- velopes 14 per cent, elongation before breaking, a second bar shall be selected from the same lot. If this bar breaks in the body and the average elongation of the two bars is not less than 16 per cent., the bars of this lot may be accepted. — 37 — Wrought Iron Grade Test Pieces Ultimate Strength Elastic Limit Elongation Bending (217) If more than one-thircl of all the bars tested break in the head, this shall be deemed sufficient cause for the rejection of the entire bill of eybars. (218) Tests of full sized sections that meet the requirements shall be paid for at cost less the scrap value of the material. Tests that fail/ to meet the require- ments will be at the expense of the Contractor. (219) All wrought iron shall be be the best double rolled and double refined iron It must be tough fibrous, uniform in quality, thoroughly welded in roll- ing and finished straight and smooth. It must be free from flaws blisters, cinder spots, cracks and imperfect edges. It must be worked from the muck bar and no steel scrap will be allowed in its manufacture. (220) Test pieces shall be prepared the same as for wrought steel. See paragraphs 197 to 200 inclusive. (221) The ultirrlate strength as determined from the test pieces shall no* be less than 50,000 oounds per square inch. (222) Tension tests of full sized bars must show an ultimate strength of at least 52,000 — 7,000 (area — perimeter) in pounds per square inch. (223) The elastic limit in no case shall be less than 26,000 pounds per square inch. (224) The elonga> ton in 8 inches shall be at least 18 per cent. (225) All iron must bend cold 180 degrees to a curve, the diameter of which is not more than twice the thickness of the piece without cracking. When nicked and bent the piece must show no signs of being- brittle, but shall bend and break gradually, showing a uniform fibrous fracture. Cast Steel Process Phosphorus Coupon. Annealing" Blow holes Ultimate Strength Elastic limit Elongation Reduction of area Cast iron Grade —38— (226) Rivet iron must be capable of being bent double and ctosed upon itself, hot or cold, without sign of fracture on the convex surface. When nicked and broken the fracture must be fibrous. (227) All steel castings shall be made by the open hearth process and shall be true to pattern and of work- manlike finish. (228) The amount of phosphorus shall not ex- ceed .08 per cent. (229) All castings shall be made with a coupon for testing which shalli not be cut off until after the castings have been annealed. (230) All castings shall be thoroughly annealed. (231) When the bearing surface of any casting is finished, there shad be no b’ow hole visible exceeding one inch in length or exceeding one-half square inch in area. The length of blow holes cut by any straight line shall never exceed one inch in any one foot. (232) The ultimate strength as determined from a J of an inch round turned from the coupon shall be from 65000 to 70000 pounds per square inch. (233) The e’astic limit shall not be less than 40000 pounds per square inch. (234) The elongation shall not be less than 15 per cent, in 2 inches. (235) The reduction of area at the point of frac- ture shall not be less than 20 per cent. (236) All iron castingss shall be made of tough, gray iron and shall be smooth, sound, true to pattern, of workmanlike finish and must be free from b’ow holes. Coupon - 39 - Tests Phosphor bronze Composition. Coupon Tests Babbitt Metal Timber Paint Oil Red Lead (237) One casting from each melt shall be made with a coupon about one inch square and 15 inches long, for testing. (238) Tests shall be made on the coupons by ap- plying a load midway between supports 12 inches apart. The test bars shall show a deflection of at least .15 inches and develope a fiber stress of at least 43000 pounds per square inch. (239) Castings of phosphor bronze shall contain 88 per cent, copper and 12 per cent, phosphorized tin. The phosphorized tin shall contain 5 per cent, phos- phorus. (240) Each casting shall be made with a coupon from which a one inch cube can be cut for testing. (241) A compression test on this cube shall show an elastic limit of not less than 20000 pounds. The per- manent set on the test cube under a load of 100000 pounds shall not exceed one-sixteenth of an inch. (242) AM babbitt metal shall be composed of 50 parts tin, 1 part copper and 5 parts antimony. (243) All timber shad generally be white, oak or long leaf yellow pine. It shall be first-class in all respects, sawed true and of full size and must be free from sap wood and large or loose knots. (244) All oil shall be bored; linseed oil and shall be of a pa'e yekow color, brilliant, limpid, drying well, with a rich luster, and having a pleasant nutty taste. Oil of a greenish or dark color, cloudy or with an uncer- tain taste will not be accepted. (245) All red lead paint shall be high grade. When properly mixed for use and applied to a smooth, vertical surface, it should neither run, separate nor sag. —40— 1st Field coat 2nd Field coat INSPECTION Inspectors- Notice of rolli Surface Inspection Subsequent discovery of defects Mirks (246) The first field coat of paint shall be the “A” brand of “Red Lead Metal Preservative,” made bv the Lowe Brothers Co., of Dayton, Ohio. (247) The second field coat of paint shall be one of the following: First, Graphite paint made by the Joseph Dixon Crucible Co., of Jersey City, N. J. Second, “Black Metal Coating No. 1407,” made by the Lowe Brothers Co., of Dayton, Olr’o. (248) The Railway Company will empMy an Inspector who will examine and test all material before any work is done upon it. He shall have free access to the mills and shops at all times during the construction of the work and shall have power to reject material when the material or workmanship does not comply with the requirements of these specifications. (249) No material shall be rolled until arrangements have been made for the proper testing and inspection of the same. (250) Each and every piece of material shall be sub- mitted to examination on all sides and for that purpose turned over when required. All plates shall be suspended for examination and each piece shall be weighed separately when required by the Inspector. (251) Acceptance of any material by the Inspector shall not prevent its subsequent rejection if found defective after delivery, and- such material shall be replaced by and at the expense of the Contractor. (252) Material, when examined at the rolling mills by the Inspector, shall when found acceptable, be stamped with his private mark. No work shall be done upon any material that does not bear this mark. Small bars, rods, facilities full ske tests MAINTE- NANCE First Painting: Second Inspection —4i~ etc., may be put up in bundles with the Inspector’s mark on a metal tag wired to the same. (253) All facilities, labor, tools and instruments ne- cessary for the inspection and testing of all material in ac- cordance with the letter and intent of these specifications shall be furnished free of expense to the Railway Company. (254) Upon request, the contractor shall be advised as to the number of pieces required for full size tests. (255) The life of a steel bridge depends quite largely upon the care it receives and in view of this fact the Author recommends. (256) That the bridge be repainced whenever the final coat becomes deteriorated and exposes the first field coat of paint. A11 efiforu should be made to at all times keep the first field coat protected. Before repaint- ing all surfaces should be thoroughly cleaned, using wire brushes and steel scrapers where necessarv. The paint used should be the same as that used for the sec- ond field coat. A marked difference in the colors of the first and second field coats has been selected in order to more clearly show when the bridge needs painting. (257) That the bridge should be inspected at frequent intervals by some competent person and any necessary repairs be made. Especially should the rivets in the floor system be tested and if any are found loose cut and replace. # APPENDIX. I -43- Table giving maximum moments (M) and end reac- tions (R) for a train of 80000 pounds street cars each 40 feet long cen er to center of couplings and upon a wheel base of 5 plus 20 plus 5 equals 30 feet and the values of w based upon M and also upon R where the equivalent load is “w pounds per lineal foot uniformly distributed plus 10 w pounds concentrated, so placed as to give the maximum effect in every case. ,, Span in feet M in foot pounds. R in pounds W based on 10 56250 30000 1 5°° 1 2000 | 12 75210 31670 1567 T 979 l6 113910 35000 1582 1945 1 20 153120 40000 i53i 2000 ! 24 211670 4667O 1604 2121 i 28 277820 5 I 43° 1654 1 1 2143 ! 3 2 355600 55000 1701 2115 1 36 433800 57780 1721 2063 1 40 5 I2 55° 60000 1708 2000 ! 44 591300 63640 1680 ! 1989 : 48 67O4OO 67920 1643 1998 i 52 749600 7 r 93° 1602 1998 : 56 85OOOO 75720 r 598 T 993 : 60 950000 80000 1583 2000 , 64 1070000 83750 x 592 1994 ! 68 I 190000 89410 i59i 2032 I 72 I 320000 93330 1594 2029 ! 76 1460000 96850 1601 2018 * 80 l600000 100000 1600 ! 2000 j 84 1780000 103800 1630 ! T 997 ! 88 1960000 107950 1650 1999 : 92 2150000 1 1 1950 1661 ! J 999 1 96 2350000 1 1 7700 1688 | 2030 I 1 bo 2550000 120000 1700 2000 j !05 2800000 125720 I 7°7 2010 j no 3050000 1 30900 1706 1 2014 1 IT 5 3400000 1 3 59oo 1752 I 2013 ! 120 3900000 140000 1857 2000 : 125 3925000 144800 1732 1 1997 ’ 150 565OOOO 170700 1 T 773 2008 1 200 9950000 | 220000 | 1809 ! 2000 i While the above table is not necessarily exact, it is close enough to illustrate the value of the loadings selected in these specifications. — 44 - Tab -e giving maximum moments (M) and end reac- tions (R) for a train of pressed steel cars weighing as fol lows : Rated capacity 100000 pounds Excess load io per cent ioooo pounds Weight of car 40000 pounds Total load for each car 150000 pounds each car having a length of 32 J feet center to center of coup- lings and a wheel base of 5 plus 15 plus 5 equals 25 feet, and the values of w based upon M and also upon R where the equivalent load is “w pounds per lineal foot uniformly dis- tributed plus 10 w pounds concentrated so placed as to give the maximum effect in every case.” W based on in feet M in foot pounds. R in pounds M 1 R IO 105460 S 62 S° 1 2812 3750 i 12 I4IOOO 59375 ! 2938 3711 i 1 6 2543OO 1 71480 3532 | 3971 ! 20 328120 84375 I 3281 4218 24 453 !oo 95312 3432 4332 ! 28 600000 103130 [ 3572 4297 32 747700 IO898O i 3595 4191 | 36 895800 117190 3555 4185' ! 40 1044200 I26560 1 348i 4219 [ 44 1 1 162500 I 355 IO 3303 4235 ’ 48 i 1387500 I 453 IO 1 340 i 4274 i 52 | 1612500 155770 3446 4327 1 56 1846900 166070 1 3472 437 ° 60 2132500 175000 3554 4375 ! 64 2428000 182810 1 36x3 4353 | 68 2690600 191360 i 3597 4349 ' 72 3028100 200520 1 3657 43 fc j 76 3375 ooo 209700 37 oi 4369 80 3750000 219140 3759 4383 i 84 4162500 229020 3811 4405 i 88 4575 ooo 239060 3851 4427 1 92 5006200 24823O 3887 4433 ' q6 5456200 25664O 3920 4425 | 100 5906200 265310 3938 4422 105 6468800 27679O 3943 4429 | 1 10 7078100 288070 3960 4432 IT 5 7687500 300000 3961 4445 1 120 8343800 312500 397 2 4465 1 125 9421900 324000 4159 4469 150 13078000 381250 4104 ! 44^6 j 200 23109000 495940 4202 4508 | While the above table is not necessarily exact, it is close enough to illus rate the value of the loadings selected in these specifications. 45 Table giving maximum moments (M) and end reac- tions (R) for various spans for E 40 loading of Theodore Cooper’s Specifications and the values of “w” based on M and also on R where the equivalent load is “w pounds per lineal foot uniformly distributed plus 10 w pounds concen- trated , so placed as to give the maximum effect in every Span in feet M in foot pounds. S in pounds w based on M 1 s IO I I25OO 60000 3000 ! 4000 ; 12 160000 70000 3333 4375 : l6 280000 85OOO 3889 1 4722 20 412500 I OOOOO 4125 1 5000 1 24 570400 I 10800 4321 5036 ! 28 73IOOO 120800 435 i 1 5033 32 910800 131500 4379 5 ° 5 8 : 36 IO97OOO ! 141100 4354 1 5°40 ; 40 131 IOOO 1 1 50800 4370 1 5027 ; 44 1543000 1 161100 4384 1 5034 : 48 I 776000 | 169600 4353 4989 52 2030000 178500 4338 4959 56 2304OOO 186000 4331 4895 ! GO 25990OO 195200 4332 4880 ! 64 291 IOOO 205200 4332 | 4886 | 68 3247000 215600 434 i 4900 i 72 3584000 226700 4339 4929 ! 26 3942000 238100 4323 1 496 1 80 4321000 248400 4321 4968 ! 84 | 4713000 259000 43 i 6 498 1 I 88 5128000 1 269400 4317 4989 1 92 5552000 ! 279600 43 ii 4993 1 96 5988000 289600 4302 4994 1 100 6440000 300000 4293 1 5000 | 105 7075000 312200 43!2 1 4994 ! no 7774000 324000 4349 4985 ; 115 8490000 335800 4375 ! 4975 ! 120 9228000 347400 4394 4963 125 1 9993000 358800 4411 1 4950 ; 150 1 141 12000 414670 4428 [ 4879 ; 200 | 23712000 | 522000 43!2 1 4745 ; Load equivalent to E 40 equals, say 5000 pounds uniform plus 50000 pounds concentrated, based on R and 4500 pounds uniform plus 45000 pounds concentrated, based on M. -46- Table giving' a comparison between the loads used in these specifications and the tpyical loads shown in Theodore Cooper’s Specifications : equals E 16. (2- 56.8 ton engines followed bv 1600 pounds per lineal foot.) equals E 24 (2- 85.2 ton engines followed by 2400 pounds per lineal foot.) (2-106.5 t° n engines followed by 300a pounds per lineal foot.) equals E 32 (2-1 13. 5 ton engines followed by 3200 pounds per lineal foot.) , 1 (2-124.2 ton engines followed by 350I} pounds per lineal foot.) equals E 40 (2-142.0 ton engines followed by 4000 pounds per Lineal foot.) equals E 48 (2-170.4 ton engines followed by 4800 pounds per Lineal foot.) (2-177.5 toil; engines followed by 5000 pounds per lineal foot.) L 20 equals E 16. L30 equals E 24 r 37-5 equals E 30 L40 equals E 32 L 43-75 equals E 35 L 50 equals E 40 L60 equals E 48 L62.S equals E 50 — 47 — « * y e or