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The Memphis Bridge : a report to George H. Nettleton... by George S. Morison
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73

» i Pft' I ; /

' i(- .I

APPENDIX O Continued.

TESTS OF STEEL EYE BARS.

TESTS ON FULL-SIZE EYE BARS. . . .

- - :')J

O/liUIli llllhijlO.

ll. . v .

t<

REMARKS. - "

Dimensions, Inches.

Results of Mechanical Tests

Span.

Original.

Reduc-

j

Elastic

Max.

Areas.

Reduc-

tion,

Elonga-

tion,

Elastic

Limit,

Max.

Load,

Phos-

phorus,

Kind op Steel.

Made by

Forged by

- - --

Nominal.

Actual.

TION OF

Limit,

Load,

Place of ,

l , ; Melt

»

Original,

After

Area,

Fracture.

Number.

Testing.

Inches.

1

Width.

Thick-

ness.

Length. C. to C.

Gauged

Length.

Width.

Thick-

ness.

Width.

Thick-

ness.

Per cent.

Inches.

Per cent.

Lbs. persq. in.

Lbs. persq. in.

Inches.

Per cent.

Per cent.

Lbs. persq. in.

Lbs. persq.in.

Per cent.

Hbi.H

?

H

258.68

228

7.01

1.27

5.31

0.90

46.3

38.2

16.8

28 640

56 830

Body

11 072

1.0200

.5402

47.0

28.1

40 790

68 730

.030

Basic open-hearth

Carnegie, Phipps & Co.

-51-

Union Bridge Co.

High steel. After test, bar cut in two, reheaded, not reannealed, test com- )

S

8

14 1

478.88

432

8.03

1.75

52.7

12.2

32 220

61 260

Not broken

10 770

1.0020

.6013

40.0

28.1

40 920

76 150

pleted as below. )

r*

it It ,

First half above. Broke in unannealed end near heat line of new head.Second half. Broke like above. Area between fracture and new head |

8

lf \U J

236.28

168

8.03

1.75

6.22

1.18

47.8

22.1

13.2

54 720

57 190

Body

10 770

10 770

«

S

8

(;

240.28

180

8.03

1.75

7.44

1.60

15.3

20.1

11.2

reduced 24.1 per cent. )

3

PS

After test. Bar cut in two, reheaded, not reannealed, retested as below.

First part of above.

Second part of above. Broke in unannealed part of bar on heat line of new (

a

C - *

8

H 1

* l

- 1 * J

478.88

432

8.00

1.26

51.7

12 0

32 380

62 93068 590

Not brokenBody

I1

10 77010 770

10 770

. J

K

HH

8

236.99

156

8.00

1.26

6.29

0.94

41.37

25.8

16.5

8

238.18

168

8.00

1.26

6.41

0.85

45.9

18.2

10.8

58 880

head. 1

<

w

T

8

1 3

MS

254.63

216

7.98

1.20

6.14

0.92

41.0

33.2

15.4

31 930

63 870

tt

10 828

1.0100

.4108

59.3

21.9

40 900

69 800

.024

<1 II tt

tt tt i|

It tt ||

8

338.58

300

8.03

2.32

6.34

1.77

39.8

34.6

11.5

32 840

62 400

tt

10 660

1.0620

.5946

44.0

23.1

41 710

71 000

.066

tt tt tl

*< tt it

ti tt tt

Soft steel suspender.

7

258.68

216

7.00

1.18

5.27

0.85

45.8

30.8

17.0

27 870

53 520

Body

20 816

1.0560

.4995

52.7

31.9

32 480

58 050

.027

Basic open-hearth

Carnegie, Phipps & Co.

Pencoyd B. & C. Co.Keystone Bridge Co.

Full capacity of machine reached.

9

338.58

300

9.00

2.31

10.5

35.3

11.8

27 730

54 400

Not broken

09 257

1.0900

.5416

50.3

29.5

39 900

66 780

., f

t(

First part.

3

9

If )

206.58

168

9.09

1.25

6.81

0.83

50.3

39.1

23.3

32 590

57 410

Body

09 405

.9734

.4488

53.8

28.7

38 110

60 920

.014

tl ft tt

ft ti tt

Second part.

W

3

9

h f

205.38

168

9.09

1.25

6.94

0.94

42.6

34.8

20.7

32 820

58 440

09 405

Lower lateral. Broke at back end of upset for screw, disclosing piece of {

PS&1

6

1 3

409.08

348

6.07

1.18

19.5

5.6

35 480

60 390

In upset for screw

3 055

.830

.435

47.6

23.0

Pencoyd I. & S. Co.

Pencoyd B. & C. Co.

iron welded in. 1

H

Lower lateral.

6

1JL

416.78

360

6.04

1.18

21.6

6.0

39 190

63 220

Sleeve nut

3 327

.672-

.303

54.9

27.5

41 670

it tt

02

11

(< ((

4

1 3

T*

' 422.18

372

4.03

0.80

3.25

0.57

42.6

39.2

10.6

40 540

71 580

Body

3 095

1.026

.436

58.5

31.3

39 280

66 090

.084

ti it tt

it it tt

fl H ll

tt <1

&

4

l

421.88

372

4.02

1.00

3.10

0.75

41.8

45.1

12.1

39 570

68 490

t <

3 095

* it tt

tt It it

it

II <i

4

H

423.08

372

4.04

1.13

3.08

0.79

46.8

47.8

12.8

39 720

69 180

If

3 095

it tt tt

ti tt tt

First part.

Second part.

8

8

Ht iHU

279.98

279.88

240

240

8.11

8.11

1.79

1.79

6.26

6.13

1.34

1.24

42.2

47.7

37.1

38.8

15.5

16.2

28 94028 660

58 01058 290

Body

11 15011 150

1.114

.5960

46.5

23.0

40 480

66 880

.030

Basic open-hearth

Carnegie, Phipps & Co.

Union Bridge Co.

First part.

£ hWOQ

7

1 l

289.23

252

7.02

1.00

5.53

0.75

40.9

44.9

17.8

31 380

59 850

11 072

1.020

.5402

47.0

28.1

40 790

68 730

.030

ft << <1

tt ti ti

Second part.

7

1 f

249.48

252

7.00

1.00

5.51

0.67

47.3

42.7

16.9

31 470

59 730

< <

11 072

Tlie first four bars were entirely experimental and did not represent bars wliicb it was intended to usein the structure. They were generally of rather too high a steel, and the result of these tests led to theadoption in the specifications of a special eye-bar steel, midway bet ween the medium and high grade steel.

Tests Nos. 5 and 6 were 6 inch bars which showed a weak steel below the requirements of thespecifications, and led to the substitution of 7 inch bars for 6 inch bars for all floor-beam suspenders, the7 inch bars being made of soft steel.

Tests 13 and 14 were both of the same bar. The first test was unsatisfactory and showed a flaw inthe steel. The second test was a test of a stretched bar relieaded after stretching, and not reannealed ;as was to be expected, it broke in the new head.

Test No. 16 showed a flaw. Test No. 17, of the same bar, when reheaded and planed down to areduced section, showed that the steel was excellent.

Test No. 18 was good. Tests Nos. 19 and 20 of the same bar broke in heads which had been forgedbut not reannealed, the last having been forged on a stretched bar.

Test 26 falls a little below the requirements of the specifications, and this was explained by a slightflaw at the fracture, the fracture taking place in the head.

Test 48 led to the rejection of the bars represented by it.