[Transcriber's Note:

1. Mathematical power (superscript) is rendered using a carat (^).

2. Superscript text is rendered using an underscore (_).]



AMERICAN SOCIETY OF CIVIL ENGINEERS

INSTITUTED 1852

TRANSACTIONS

Paper No. 1168

TESTS OF CREOSOTED TIMBER.

BY W. B. GREGORY, M. AM. SOC. C. E.



During the last few years a quantity of literature has appeared in which the treatment of timber by preservatives has been discussed. The properties of timber, both treated and untreated, have been determined by the Forest Service, United States Department of Agriculture, and through its researches valuable knowledge has come to engineers who have to deal with the design of wooden structures. There is very little information, however, regarding the effect of time on creosoted timber, and for this reason the results given herewith may prove of interest.

The material tested consisted of southern pine stringers having a cross-section approximately 6 by 16 in. and a length of 30 ft. For the purpose of testing, each beam was cut into two parts, each about 15 ft. long. This material had been in use in a trestle of a railroad near New Orleans for 26 years. The stringers were chosen at random to determine the general condition of the trestle. The timber had been exposed to the weather and subjected to heavy train service from the time it was treated until it was tested. The annual rainfall at New Orleans is about 60 in., and the humidity of the air is high. In spite of these conditions, there was no appearance of decay on any of the specimens tested. The specifications under which the timber was treated were as follows:

TIMBER.

The timber for creosoting shall be long-leafed or southern pine. Sap surfaces on two or more sides are preferred.

Piles.—The piles shall be of long-leafed or southern pine, not less than 14 in. at the butt. They shall be free from defects impairing their strength, and shall be reasonably straight.

The piles shall be cleanly peeled, no inner skin being left on them. The oil used shall be so-called creosote oil, from London, England, and shall be of a heavy quality.

The treatment will vary according to the dimensions of the timbers and length of time they have been cut. Timbers of large and small dimensions shall not be treated in the same charge, neither shall timbers of differing stages of air seasoning, or the close-grained, be treated in the same charge with coarse or open-grained timbers.

The timbers shall be subjected first to live steam superheated to from 250 to 275 deg. Fahr., and under a 30 to 40-lb. pressure. The live steam shall be admitted into the cylinders through perforated steam pipes, and the temperature shall be obtained by using superheated steam in closed pipes in the cylinders.

The length of time this steaming shall last will depend on the size of the timbers and the length of time they have been cut. In piles and large timbers freshly cut, as long a time as 12 hours may be required. After the steaming is accomplished, the live steam shall be shut off and the superheated steam shall be maintained at a temperature of 160 deg. or more and a vacuum of from 20 to 25 in. shall be held for 4 hours or longer, if the discharge from the pumps indicates the necessity.

Oil Treatment.—The temperature being maintained at 160 deg. Fahr., the cylinders shall be promptly filled with creosote oil at a temperature as high as practicable (about 100 deg. Fahr.). The oil shall be maintained at a pressure ranging from 100 to 120 lb., as experience and measurements must determine the length of time the oil treatment shall continue, so that the required amount of oil may be injected.

After the required amount of oil is injected, the superheated steam shall be shut off, the oil let out, the cylinders promptly opened at each end, and the timber immediately removed from the cylinder.

In the erection of timbers the sap side must be turned up, and framing or cutting of timbers shall not be permitted, if avoidable. All cut surfaces of timbers shall be saturated with hot asphaltum, thinned with creosote oil. The heads of piles when cut shall be promptly coated with the hot asphaltum and oil, even though the cut-off be temporary.

METHOD OF TESTING.

The tests were made on a Riehle 100,000-lb. machine in the Experimental Engineering Laboratory of Tulane University of Louisiana. The machine is provided with a cast-iron beam for cross-bending tests. The distance between supports was 12 ft. The method of support was as follows: Each end of the beam was provided with a steel roller which rested on the cast-iron beam of the testing machine, while above the roller, and, directly under the beam tested, there was a steel plate 6 by 8 in. in area and 1 in. thick. The area was sufficiently great to distribute the load and prevent the shearing of the fibers of the wood. The head of the Riehle machine is 10 in. wide. A plate, 3/8 in. thick, 6 in. wide and 18 in. long, was placed between the head of the machine and the beam tested.



TABLE 1.—SUMMARY OF RESULTS OF TRANSVERSE TESTS OF BEAMS AT TULANE UNIVERSITY, FEBRUARY 10TH TO MARCH 2D, 1909.

Columns in table:

1. Number of beam. 2. Top or butt of log. 3. Width, in inches. 4. Height, in inches. 5. I = (bh^3)/12 6. Actual at elastic limit. 7. Maximum. 8. At elastic limit. 9. Maximum. 10. At elastic limit. 11. E = (Pl^3)/(48dI) 12. Weight, in pounds per cubic foot.

===========================================================================+ b h I LOADS: S = (Plc)/(4I) d, INCHES. + - - - - -+ 1 2 3 4 5 6 7 8 9 10 + - - - - - -+ I B 6.28 15.94 2,120 22,000 45,900 2,975 6,200 0.41 I T 6.00 15.69 1,934 20,000 38,000 2,915 5,540 0.465 II[A] T 6.37 15.81 2,098 20,000 43,450 2,722 5,918 0.380 II B 6.41 16.41 2,360 16,000 25,040 1,999 3,130 0.430 III T 5.88 15.68 1,871 24,000 45,130 3,608 6,785 0.535 III B 5.88 15.90 1,965 21,000 35,190 3,054 5,120 0.515 IV T 6.00 15.43 1,835 22,000 38,425 3,320 5,810 0.465 IV B 6.12 15.87 2,032 22,000 35,500 3,090 4,983 0.660 V B 6.00 16.00 2,048 22,000 47,000 3,090 6,610 0.400 V[A] T 6.00 15.87 1,999 14,000 22,050 1,998 3,145 0.315 VI[A] B 5.50 15.75 1,790 22,000 51,330 3,484 8,925 0.450 VI[A] T 5.87 15.62 1,865 20,000 44,000 3,013 6,627 0.410 VII B 6.56 15.62 2,083 34,000 51,900 4,580 6,985 0.620 VII[A] T 6.22 15.62 1,975 20,000 49,000 2,845 6,970 0.380 ===========================================================================+

[Footnote A: Failed in longitudinal shear.]

============================================== E -+ 11 12 Remarks. -+ + - 1,575,000 50.2 } Close-grained pine, 1,383,000 47.5 } long-leaf. 1,562,000 40.5 } Coarse loblolly, 979,000 42.2 } large knots. 1,489,000 40.4 } Close-grained, long-leaf 1,288,000 44.2 } no knots. 1,601,000 40.8 } Loblolly, with 1,017,000 41.5 } knots. 1,670,000 47.2 } Long-leaf yellow 1,382,000 42.1 } pine. 1,695,000 50.2 } Long-leaf yellow 1,625,000 45.2 } pine. 1,637,000 43.7 } Long-leaf yellow 1,658,000 40.2 } pine. ==============================================

The deflection was measured on both sides of each beam by using silk threads stretched on each side from nails driven about 2 in. above the bottom of the beam and directly over the rollers which formed the supports. From a small piece of wood, tacked to the bottom of the beam at its center and projecting at the sides, the distance to these threads was measured. These measurements were taken to the nearest hundredth of an inch. The mean of the deflections was taken as the true deflection for any load.



In computing the various quantities shown in Table 1, the summary of results, the load has been assumed as concentrated at the center of the beam. While it is true that the load was spread over a length of about 12 in., due to the width of the head of the machine and the plate between it and the beam tested, it is also true that there were irregularities, such as bolt-holes and, in some cases, abrasions due to wear, that could not well be taken into account. Hence, it was deemed sufficiently accurate to consider the load as concentrated. Besides the horizontal bolt-holes, shown in the photographs, there were vertical bolt-holes, at intervals in all the beams. The latter were 7/8 in. in diameter, and in every case they were sufficiently removed from the center of the length of the beam to allow the maximum moment at the reduced section to be relatively less than that at the center of the beam. For this reason, no correction was made for these holes. The broken beams often showed that rupture started at, or was influenced by, some of the holes, especially the horizontal ones.

While some of the heavy oils of a tarry consistency remained, they were only to be found in the sappy portions of the long-leaf pine and in the loblolly (Specimens II and IV). Exposure in a semi-tropical climate for 26 years had resulted in the removal of the more volatile portions of the creosote oil. The penetration of the oil into the sap wood seemed to be perfect, while in the loblolly it varied from a fraction of an inch to 1-1/2 in. In the heart wood there was very little penetration across the grain. The timber had been framed and the holes bored before treatment. The penetration of the creosote along the grain from the holes was often from 4 to 6 in.

Circular 39 of the Forest Service, U. S. Department of Agriculture, entitled "Experiments on the Strength of Treated Timber," gives the results of a great many tests of creosoted ties, principally loblolly pine, from which the following conclusions are quoted:

"(1) A high degree of steaming is injurious to wood. The degree of steaming at which pronounced harm results will depend upon the quality of the wood and its degree of seasoning, and upon the pressure (temperature) of steam and the duration of its application. For loblolly pine the limit of safety is certainly 30 pounds for 4 hours, or 20 pounds for 6 hours." [Tables 3, 6, and 7.]

"(2) The presence of zinc chlorid will not weaken wood under static loading, although the indications are that the wood becomes brittle under impact." [Tables 3 and 4.]



"(3) The presence of creosote will not weaken wood of itself. Since apparently it is present only in the openings of the cells, and does not get into the cell walls, its action can only be to retard the seasoning of the wood." [Tables 3, 4, 5, and 6.]



COMPARISONS.

A comparison of the results obtained with tests made on untreated timber is interesting, and to this end Tables 2 and 3, from Circular 115, Forest Service, U. S. Department of Agriculture, by W. Kendrick Hatt, Assoc. M. Am. Soc. C. E., are quoted. The tests made by the writer were from timber raised in Louisiana and Mississippi, while the tests quoted were from timber raised farther north. The number of tests was not sufficient to settle questions of average strength or other qualities. It will be seen, however, that the treated timber 26 years old compares favorably with the new untreated timber.



TABLE 2.—BENDING STRENGTH OF LARGE STICKS.

Columns in table:

A: Reference number. B: Number of tests. C: Moisture, per cent. D: Rings per inch. E: Specific gravity, dry. F: WEIGHT PER CUBIC FOOT, IN POUNDS. G: As tested. H: Oven dry. I: Fiber stress at elastic limit, in pounds per square inch. J: Modulus of rupture, in pounds per square inch. K: Modulus of elasticity, in thousands of pounds per square inch. L: Elastic resilience, in inch pounds per cubic inch. M: Number failing by longitudinal shear.

LOBLOLLY PINE.

======================================================================== Locality DIMENSIONS. of Grade. Condition A Growth. Section, Span, of B C D in in seasoning. inches. feet - - - - - - - + 6 by 7 6 by 10 10 1 South 4 by 12 to Square Green Average 48.0 5.7 Carolina. 6 by 16 15.5 edge Maximum 42 92.1 11.7 8 by 14 Minimum 30.2 2.3 8 by 16 + - - - - - - - 6 by 7 4 by 12 10 2 South 6 by 10 to Square Partially Average 27.7 5.0 Carolina. 6 by 16 16 edge air dry. Maximum 18 29.2 8.2 8 by 16 Minimum 25.5 2.5 10 by 16 - - - - - - - + 6 by 7 10 South 4 by 12 to Square Partially Average 21.0 5.6 3 Carolina. 6 by 10 15 edge air dry. Maximum 19 24.9 17.2 6 by 16 Minimum 15.0 2.7 + - - - - - - - 6 Average 22.4 4.8 4 Virginia. 8 by 8 to Square Partially Maximum 12 27.7 8.8 16 edge air dry. Minimum 17.8 2.5 - - - - - - - + 6 Average 64.0 3.0 5 Virginia. 8 by 8 to Square Green Maximum 17 100.5 4.0 15.5 edge Minimum 38.8 2.5 + - - - - - - -

LONG-LEAF PINE.

- - - - - - - + Average 25.0 13.7 6 South 6 by 8 15 Merchant- Partially Maximum 22 40.3 25.4 Carolina. 10 by 16 able air dry Minimum 17.3 6.2 + - - - - - - - Average 27.3 18.0 7 Georgia. 10 by 12 15 Merchant- Partially Maximum 22 34.5 29.0 able air dry. Minimum 20.0 11.0 ========================================================================

===================================================================== Locality F of - A Growth. E I J K L M Remarks. G H - - - - - Moisture above 1 South 0.50 46.2 31.2 3,150 5,580 1,426 0.45 saturation Carolina. 0.60 56.8 37.5 5,210 8,460 1,920 0.99 7 point in 0.40 35.6 25.0 1,675 3,120 905 0.07 all cases. - - - - - 2 South 0.50 40.0 31.2 3,380 5,650 1,435 0.45 Moisture Carolina. 0.55 43.7 34.4 4,610 8,090 1,880 0.76 0 from 25 to 0.45 35.6 28.1 2,115 3,600 1,152 0.20 30 per cent. - - - - - South 0.50 37.5 31.2 2,970 5,690 1,340 0.39 Moisture 3 Carolina. 0.58 45.6 36.2 4,850 8,100 2,040 0.69 2 less than 0.41 31.2 25.6 1,730 2,910 906 0.10 25 per cent. - - - - - 0.46 35.6 28.8 3,260 5,180 1,180 0.51 4 Virginia. 0.58 43.1 36.2 5,300 8,950 1,728 1.05 0 0.37 30.0 23.1 1,280 2,180 606 0.13 - - - - - 0.43 43.7 26.9 1,935 3,490 744 0.31 Very rapid 5 Virginia. 0.51 51.9 31.9 3,185 4,720 1,193 0.78 0 growth; poor 0.35 35.0 21.9 956 2,180 357 0.12 quality. - - - - -

LONG-LEAF PINE.

- - - - - 0.58 45.6 36.2 3,800 7,160 1,560 0.53 6 South 0.76 60.0 47.5 4,970 10,020 2,010 0.78 9 Carolina. 0.50 39.4 31.2 2,220 5,450 1,190 0.21 - - - - - 0.69 54.7 42.9 5,581 8,384 1,820 Excellent 7 Georgia. 0.79 49.4 9,600 11,410 2,920 6 merchantable 0.50 31.4 3,547 4,836 1,167 grade. =====================================================================

TABLE 3.—LOBLOLLY PINE.—BENDING TESTS ON BEAMS SEASONED UNDER DIFFERENT CONDITIONS.

(8 by 16-in. section; 13-1/2 to 15-ft. span.)

Columns in table:

A. Number of tests. B. Fiber stress at elastic limit, in pounds per square inch. C. Modulus of rupture, in pounds per square inch. D. Longitudinal shear at maximum load, in pounds per square inch. E. Modulus of elasticity, in thousands of pounds per square inch. F. Percentage of moisture. G. Rings per inch. H. Weight per cubic foot, oven dry, in pounds. I. Condition of seasoning.

==================================================================== A B C D E F G H I + -+ -+ -+ -+ -+ + + + Average 3,580 5,480 364_{4} 1,780 23.2 9.4 33.7 Air dry, Maximum 4 4,070 6,600 440 1,987 24.3 11.5 34.5 3-1/2 months Minimum 3,090 5,000 327 1,530 21.5 8.0 32.5 in the open. + -+ -+ -+ -+ -+ + + + Average 4,512 5,060 338_{3} 1,685 20 7.7 33.9 Kiln dry, Maximum 5 5,840 7,320 488 1,790 22 10.2 38.0 6 days. Minimum 3,180 2,150 143 1,410 18 4.7 27.7 + -+ -+ -+ -+ -+ + + + Average 4,331 6,721 493_{9} 1,688 7.7 Air dry, 21 Maximum 12 4,990 8,560 620 2,002 9.5 months under Minimum 3,110 5,160 380 1,398 5.5 shelter. ====================================================================

NOTE.—Figures written as subscripts to the figures for longitudinal shear indicate the number of sticks failing in that manner.



TABLE 4.—LOAD AND DEFLECTION LOG. BEAM I.

Columns in table:

A: Load, in pounds. B: Reading. C: Total deflection. D: Mean total deflection.

Date: February 26th, 1909. Date: February 24th, 1909. l = 12 ft.; l = 12 ft.; b (mean) = 6-9/32 in.; b (mean) = 6 in.; h (mean) = 15-15/16 in.; h (mean) = 15.69 in.; c = 7.97 in. c = 7.84 in. Time = 1 hour.

========================================================================= P DEFLECTION, IN INCHES. P DEFLECTION, IN INCHES. No. - - - A B C B C D A B C B C D - - - - 1 0 1.86 0 1.88 0 0 0 1.83 0 1.86 0 0 2 2,000 1.92 0.05 1.90 0.02 0.035 2,000 1.87 0.04 1.90 0.04 0.04 3 4,000 1.96 0.10 1.94 0.06 0.080 4,000 1.91 0.08 1.96 0.10 0.090 4 6,000 1.99 0.13 1.98 0.10 0.115 6,000 1.96 0.13 2.00 0.14 0.135 5 8,000 2.03 0.17 2.02 0.14 0.155 8,000 2.00 0.17 2.04 0.18 0.175 6 10,000 2.05 0.19 2.06 0.18 0.185 10,000 2.04 0.21 2.08 0.22 0.215 7 12,000 2.10 0.24 2.09 0.21 0.225 12,000 2.09 0.26 2.13 0.27 0.265 8 14,000 2.13 0.27 2.13 0.25 0.260 14,000 2.14 0.31 2.18 0.32 0.315 9 16,000 2.17 0.31 2.16 0.28 0.295 16,000 2.19 0.36 2.23 0.37 0.365 10 18,000 2.20 0.34 2.20 0.32 0.330 18,000 2.24 0.41 2.28 0.42 0.415 11 20,000 2.24 0.36 2.25 0.37 0.365 20,000 2.29 0.46 2.33 0.47 0.465 12 22,000 2.28 0.42 2.28 0.40 0.410 22,000 2.34 0.51 2.39 0.53 0.520 13 24,000 2.32 0.46 2.32 0.44 0.450 24,000 2.39 0.56 2.43 0.57 0.565 14 26,000 2.36 0.50 2.36 0.48 0.490 26,000 2.44 0.61 2.48 0.62 0.615 15 28,000 2.40 0.54 2.39 0.51 0.525 28,000 2.49 0.66 2.53 0.67 0.685 16 30,000 2.43 0.57 2.44 0.56 0.565 30,000 2.55 0.72 2.58 0.72 0.720 17 32,000 2.48 0.62 2.48 0.60 0.610 32,000 2.61 0.78 2.65 0.79 0.785 18 34,000 2.52 0.68 2.53 0.65 0.655 34,000[B] 2.68 0.85 2.70 0.84 0.845 19 36,000 2.56 0.70 2.56 0.68 0.690 36,000 2.74 0.91 2.78 0.92 0.915 20 38,000 2.61 0.75 2.62 0.74 0.745 38,000 Broke. 21 40,000 2.65 0.79 2.67 0.79 0.790 22 42,000 2.70 0.84 2.73 0.85 0.845 23 44,000 2.75 0.89 2.77 0.89 0.890 37,500 lb., First Crack; 45,900 lb., Failed. At Elastic Limit: Load, 22,000 lb.; At Elastic Limit: Load, 20,000 lb.; deflection, 0.41 in.; deflection, 0.465 in.; S, 2,975 lb. S, 2,975 lb. Maximum: Load, 45,900 lb.; Maximum: Load, 38,000 lb.; deflection,.....; deflection,.....; S, 6,209 lb. S, 5,540 lb. E = 1,575,000 lb. E = 1,383,000 lb. =========================================================================

[Footnote B: First crack.]

TABLE 4.—(Continued.)—LOAD AND DEFLECTION LOG. BEAM II.

Columns in table:

A: Load, in pounds. B: Reading. C: Total deflection. D: Mean total deflection.

Date: February 20th, 1909. Date: — l = 12 ft.; l = 12 ft.; b (mean) = 6.38 in.; b (mean) = 6.41 in.; h (mean) = 15.81 in.; h (mean) = 16.41 in.; c = 7.91 in. c = 8.20 in. Time = 47.5 min.

========================================================================= P DEFLECTION, IN INCHES. P DEFLECTION, IN INCHES. No. - - - A B C B C D A B C B C D - - - - 1 0 1.65 0 1.68 0 0 0 1.86 0 1.87 0 0 2 2,000 1.69 0.04 1.72 0.04 0.040 2,000 1.91 0.05 1.92 0.05 0.05 3 4,000 1.73 0.08 1.77 0.09 0.085 4,000 1.98 0.12 1.98 0.11 0.115 4 6,000 1.76 0.11 1.80 0.12 0.115 6,000 2.05 0.19 2.02 0.15 0.170 5 8,000 1.80 0.15 1.83 0.15 0.150 8,000 2.07 0.21 2.08 0.21 0.210 6 10,000 1.83 0.18 1.86 0.18 0.180 10,000 2.13 0.27 2.13 0.26 0.265 7 12,000 1.87 0.22 1.90 0.22 0.220 12,000 2.18 0.32 2.18 0.31 0.315 8 14,000 1.91 0.26 1.94 0.26 0.260 14,000 2.25 0.39 2.24 0.37 0.380 9 16,000 1.95 0.30 1.98 0.30 0.300 16,000 2.30 0.44 2.29 0.42 0.430 10 18,000 1.98 0.33 2.02 0.34 0.335 18,000[C] 2.35 0.49 2.35 0.48 0.485 11 20,000 2.03 0.38 2.06 0.38 0.380 20,000 2.44 0.58 2.42 0.55 0.565 12 22,000 2.07 0.42 2.10 0.42 0.420 22,000 2.54 0.68 2.54 0.67 0.675 13 24,000 2.11 0.46 2.14 0.46 0.460 25,040 Failed 14 26,000 2.15 0.50 2.18 0.50 0.500 15 28,000 2.18 0.53 2.22 0.54 0.535 16 30,000 2.23 0.58 2.26 0.58 0.580 17 32,000 2.27 0.62 2.30 0.62 0.620 18 34,000 2.32 0.67 2.35 0.67 0.670 19 36,000 2.37 0.72 2.40 0.72 0.720 20 38,000 2.42 0.77 2.45 0.77 0.770 21 40,000 2.48 0.83 2.50 0.82 0.825 22 42,000 2.53 0.88 2.56 0.88 0.880 23 43,450 Fracture. 24 45,710 Failed. At Elastic Limit: Load, 20,000 lb.; At Elastic Limit: Load, 16,000 lb.; deflection, 0.38 in.; deflection, 0.43 in.; S, 2,722 lb. S, 1,999 lb. Maximum: Load, 43,450 lb.; Maximum: Load, 25,040 lb.; deflection,.....; deflection,.....; S, 5,918 lb. S, 3,130 lb. E = 1,562,000 lb. E = 979,000 lb. ==========================================================================

[Footnote C: First crack.]

TABLE 4.—(Continued.)—LOAD AND DEFLECTION LOG. BEAM III.

Columns in table:

A: Load, in pounds. B: Reading. C: Total deflection. D: Mean total deflection.

Date: February 13th, 1909. Date: — l = 12 ft.; l = 12 ft.; b (mean) = 5.88 in.; b (mean) = 5.88 in.; h (mean) = 15.63 in.; h (mean) = 15.9 in.; c = 7.82 in. c = 7.95 in. Time = 45 min.

========================================================================= P DEFLECTION, IN INCHES. P DEFLECTION, IN INCHES. No. - - - A B C B C D A B C B C D - - - - 1 0 1.23 0 1.06 0 0 0 1.67 0 1.63 0 0 2 2,000 1.27 .04 1.10 0.04 0.040 2,000 1.70 0.03 1.68 0.05 0.040 3 4,000 1.32 0.09 1.13 0.07 0.080 4,000 1.72 0.05 1.72 0.09 0.070 4 6,000 1.37 0.14 1.17 0.11 0.125 6,000 1.82 0.15 1.78 0.15 0.150 5 8,000 1.42 0.19 1.22 0.16 0.175 8,000 1.86 0.19 1.82 0.19 0.190 6 10,000 1.47 0.24 1.26 0.20 0.220 10,000 1.90 0.23 1.87 0.24 0.235 7 12,000 1.51 0.28 1.31 0.25 0.265 12,000 1.97 0.30 1.92 0.29 0.295 8 14,000 1.55 0.32 1.35 0.29 0.305 14,000 2.00 0.33 1.98 0.35 0.340 9 16,000 1.60 0.37 1.40 0.34 0.355 16,000 2.03 0.36 2.04 0.41 0.385 10 18,000 1.64 0.41 1.44 0.38 0.395 18,000 2.10 0.43 2.09 0.46 0.445 11 20,000 1.68 0.45 1.49 0.43 0.440 20,000 2.13 0.46 2.14 0.51 0.485 12 22,000 1.72 0.49 1.54 0.48 0.485 22,000 2.20 0.53 2.20 0.57 0.550 13 24,000 1.78 0.55 1.58 0.52 0.535 24,000 2.26 0.59 2.26 0.63 0.610 14 26,000 1.82 0.59 1.64 0.58 0.585 26,000 2.31 0.64 2.32 0.69 0.665 15 28,000 1.88 0.65 1.68 0.62 0.635 28,000 2.38 0.71 2.40 0.77 0.740 16 30,000 1.92 0.69 1.73 0.67 0.680 30,000 2.42 0.75 2.47 0.84 0.795 17 32,000 1.97 0.74 1.79 0.73 0.735 32,000 2.49 0.82 2.55 0.92 0.870 18 34,000 2.02 0.79 1.85 0.79 0.790 34,000 2.58 0.91 2.62 0.99 0.950 19 36,000 2.07 0.84 1.90 0.84 0.840 20 38,000 2.13 0.90 1.97 0.91 0.915 21 40,000 2.20 0.97 2.03 0.97 0.970 22 42,000 2.27 1.04 2.11 1.05 1.045 23 44,000 2.37 1.14 2.21 1.15 1.145 39,100 lb. First Crack; 22,000 lb. First Crack; 45,130 lb. Failed. 35,190 lb. Failed. At Elastic Limit: Load, 24,000 lb.; At Elastic Limit: Load, 21,000 lb.; deflection, 0.535 in.; deflection, 0.515 in.; S 3,608 lb. S, 3,054 lb. Maximum: Load, 45,130 lb.; Maximum: Load, 35,190 lb.; deflection,.....; deflection,.....; S 6,785 lb. S 5,120 lb. E = 1,489,000 lb. E = 1,288,000 lb. ==========================================================================

TABLE 4.—(Continued.)—LOAD AND DEFLECTION LOG. BEAM IV.

Columns in table:

A: Load, in pounds. B: Reading. C: Total deflection. D: Mean total deflection.

Date: February 16th, 1909. Date: February 10th, 1909. l = 12 ft.; l = 12 ft.; b (mean) = 6.0 in.; b (mean) = 6.12 in.; h (mean) = 15.43 in.; h (mean) = 15.87 in.; c = 7.71 in. c = 7.93 in. Time = 30 min.

========================================================================= P DEFLECTION, IN INCHES. P DEFLECTION, IN INCHES. No. - - - A B C B C D A B C B C D - - - - 1 0 2.28 0 2.05 0 0 0 1.44 0 1.58 0 0 2 2,000 2.31 0.03 2.10 0.05 0.040 2,000 1.50 0.06 1.64 0.06 0.06 3 4,000 2,34 0.06 2.14 0.09 0.075 4,000 1.55 0.11 1.70 0.12 0.115 4 6,000 2.40 0.12 2.19 0.14 0.130 6,000 1.62 0.18 1.76 0.18 0.180 5 8,000 2.43 0.15 2.23 0.18 0.165 8,000 1.68 0.24 1.82 0.24 0.240 6 10,000 2.47 0.19 2.28 0.23 0.210 10,000 1.72 0.28 1.89 0.31 0.295 7 12,000 2.51 0.23 2.32 0.27 0.250 12,000 1.80 0.36 1.94 0.36 0.360 8 14,000 2.54 0.26 2.37 0.32 0.290 14,000 1.85 0.41 2.00 0.42 0.415 9 16,000 2.59 0.31 2.41 0.36 0.335 16,000 1.90 0.46 2.06 0.48 0.470 10 18,000 2.62 0.34 2.45 0.40 0.370 18,000 1.98 0.54 2.13 0.55 0.545 11 20,000 2.68 0.40 2.50 0.45 0.425 20,000 2.03 0.59 2.19 0.61 0.600 12 22,000 2.72 0.44 2.54 0.49 0.465 22,000 2.09 0.65 2.25 0.67 0.660 13 24,000 2.78 0.50 2.60 0.55 0.525 24,000 2.15 0.71 2.33 0.75 0.730 14 26,000 2.82 0.54 2.65 0.60 0.570 26,000 2.23 0.79 2.42 0.84 0.815 15 28,000 2.87 0.59 2.69 0.64 0.615 28,000 2.32 0.88 2.49 0.91 0.895 16 30,000 2.91 0.63 2.74 0.69 0.660 30,000 2.42 0.98 2.62 1.04 1.010 17 32,000 2.97 0.69 2.78 0.73 0.710 32,000 2.56 1.12 2.74 1.16 1.140 18 34,000 3.01 0.73 2.85 0.80 0.765 34,000 2.67 1.23 2.87 1.29 1.265 19 36,000 3.07 0.79 2.90 0.85 0.820 20 38,000 3.14 0.86 2.98 0.93 0.895 34,000 lb. First Crack; 28,360 lb. Cracked; 38,425 lb. Failed. 35,500 lb, Failed. At Elastic Limit: Load, 22,000 lb.; At Elastic Limit: Load, 22,000 lb.; deflection, 0.465 in.; deflection, 0.66 in.; S 3,320 lb. S, 3,090 lb. Maximum: Load, 38,425 lb.; Maximum: Load, 35,500 lb.; deflection,.....; deflection,.....; S 5,810 lb. S 4,983 lb. E = 1,601,000 lb. E = 1,017,000 lb. ==========================================================================

TABLE 4.—(Continued.)—LOAD AND DEFLECTION LOG. BEAM V.

Columns in table:

A: Load, in pounds. B: Reading. C: Total deflection. D: Mean total deflection.

Date: — Date: February 27th, 1909. l = 12 ft.; l = 12 ft.; b (mean) = 6 in.; b (mean) = 6 in.; h (mean) = 16 in.; h (mean) = 15.87 in.; c = 8 in. c = 7.94 in. Time = 40 min.

========================================================================= P DEFLECTION, IN INCHES. P DEFLECTION, IN INCHES. No. - - - A B C B C D A B C B C D - - - - 1 0 1.97 0 1.37 0 0 0 1.31 0 1.25 0 0 2 2,000 2.01 0.04 1.40 0.03 0.035 2,000 1.37 0.06 1.31 0.06 0.06 3 4,000 2.06 0.09 1.43 0.06 0.075 4,000 1.41 0.10 0.36 0.11 0.105 4 6,000 2.08 0.11 1.47 0.10 0.105 6,000 1.46 0.15 0.40 0.15 0.150 5 8,000 2.11 0.14 1.50 0.13 0.135 8,000 1.49 0.18 0.45 0.20 0.190 6 10,000 2.16 0.19 1.54 0.17 0.180 10,000 1.54 0.23 1.49 0.24 0.235 7 12,000 2.19 0.22 1.57 0.20 0.210 12,000 1.58 0.27 1.53 0.28 0.275 8 14,000 2.22 0.25 1.61 0.24 0.245 14,000 1.62 0.31 1.57 0.32 0.315 9 16,000 2.25 0.28 1.65 0.28 0.280 16,000 1.68 0.37 1.65 0.40 0.385 10 18,000 2.29 0.32 1,69 0.32 0.320 18,000 1.78 0.41 1.71 0.46 0.435 11 20,000 2.32 0.35 1.73 0.36 0.355 20,000 1.99 0.68 1.97 0.72 0.700 12 22,000 2.36 0.39 1.78 0.41 0.400 13 24,000 2.39 0.42 1.83 0.46 0.440 14 26,000 2.42 0.45 1.85 0.48 0.465 15 28,000 2.47 0.50 1.90 0.53 0.515 16 30,000 2.50 0.53 1.95 0.58 0.565 17 32,000 2.54 0.57 1.99 0.62 0.595 18 34,000 2.59 0.62 2.04 0.67 0.645 19 36,000 2.63 0.66 2.09 0.72 0.690 20 38,000 2.68 0.71 2.17 0.80 0.755 21 40,000 2.73 0.76 2.21 0.84 0.800 22 42,000 2.80 0.83 2.30 0.93 0.880 23 44,000 2.90 0.93 2.40 1.03 0.980 25,000 lb. Slight Crack; 20,000 lb. First Crack; 47,000 lb. Failed. 22,050 lb. Failed. At Elastic Limit: Load, 22,000 lb.; At Elastic Limit: Load, 14,000 lb.; deflection, 0.40 in.; deflection, 0.315 in.; S, 3,090 lb. S, 1,998 lb. Maximum: Load, 47,000 lb.; Maximum: Load, 22,050 lb.; deflection,.......; deflection,.......; S, 6,610 lb. S, 3,145 lb. E = 1,670,000 lb. E = 1,382,000 lb. =========================================================================

TABLE 4.—(Continued.)—LOAD AND DEFLECTION LOG. BEAM VI.

Columns in table:

A: Load, in pounds. B: Reading. C: Total deflection. D: Mean total deflection.

Date: February 12th, 1909. Date: February 13th, 1909. l = 12 ft.; l = 12 ft.; b (mean) = 5.5 in.; b (mean) = 5.87 in.; h (mean) = 15.75 in.; h (mean) = 15.62 in.; c = 7.88 in. c = 7.81 in. Time = 40 min.

========================================================================= P DEFLECTION, IN INCHES. P DEFLECTION, IN INCHES. No. - - - A B C B C D A B C B C D - - - - 1 0 1.22 0 1.30 0 0 0 1.28 0 1.30 0 0 2 2,000 1.26 0.04 1.34 0.04 0.04 2,000 1.30 0.02 1.35 0.05 0.035 3 4,000 1.29 0.07 1.38 0.08 0.075 4,000 1.36 0.08 1.39 0.09 0.085 4 6,000 1.33 0.11 1.42 0.12 0.115 6,000 1.40 0.12 1.44 0.14 0.130 5 8,000 1.37 0.15 1.47 0.17 0.160 8,000 1.43 0.15 1.47 0.17 0.160 6 10,000 1.42 0.20 1.51 0.21 0.205 10,000 1.47 0.19 1.51 0.21 0.200 7 12,000 1.45 0.23 1.55 0.25 0.240 12,000 1.51 0.23 1.56 0.26 0.245 8 14,000 1.50 0.28 1.59 0.29 0.285 14,000 1.55 0.27 1.60 0.30 0.285 9 16,000 1.54 0.32 1.63 0.33 0.325 16,000 1.59 0.31 1.64 0.34 0.325 10 18,000 1.58 0.36 1.68 0.38 0.370 18,000 1.62 0.34 1.69 0.39 0.365 11 20,000 1.61 0.39 1.72 0.42 0.405 20,000 1.66 0.38 1.74 0.44 0.410 12 22,000 1.66 0.44 1.76 0.46 0.450 22,000 1.71 0.43 1.80 0.50 0.465 13 24,000 1.81 0.59 1.81 0.51 0.550 24,000 1.77 0.49 1.84 0.54 0.515 14 26,000 1.86 0.64 1.86 0.56 0.600 26,000 1.83 0.55 1.90 0.60 0.575 15 28,000 1.91 0.69 1.91 0.61 0.650 28,000 1.90 0.62 1.97 0.67 0.645 16 30,000 1.96 0.74 1.96 0.66 0.700 30,000 1.97 0.69 2.02 0.72 0.705 17 32,000 2.00 0.78 2.02 0.72 0.750 32,000 2.12 0.84 2.10 0.80 0.820 18 34,000 2.04 0.82 2.11 0.81 0.815 34,000 2.20 0.92 2.16 0.86 0.885 19 36,000 2.10 0.88 2.20 0.90 0.890 36,000 2.29 1.01 2.24 0.94 0.975 20 38,000 2.16 0.94 2.25 0.95 0.945 38,000 2.39 1.11 2.32 1.02 1.065 21 40,000 2.28 1.06 2.38 1.08 1.070 22 42,000 2.38 1.16 2.42 1.12 1.140 23 44,000 2.44 1.22 2.52 1.22 1.220 24 46,000 2.53 1.31 2.60 1.30 1.305 25 48,000 2.66 1.44 2.71 1.41 1.425 26 50,000 2.78 1.56 2.87 1.57 1.565 33,000 lb., First Crack; 24,000 lb., First Crack; 51,330 lb., Failed. 44,000 lb., Failed. At Elastic Limit: Load, 22,000 lb.; At Elastic Limit: Load, 20,000 lb.; deflection, 0.45 in.; deflection, 0.41 in.; S, 3,484 lb. S, 3,018 lb. Maximum: Load, 51,330 lb.; Maximum: Load, 44,000 lb.; deflection,.....; deflection,.....; S, 8,925 lb. S, 6,627 lb. E = 1,695,000 lb. E = 1,625,000 lb. =========================================================================

TABLE 4.—(Continued.)—LOAD AND DEFLECTION LOG. BEAM VII.

Columns in table:

A: Load, in pounds. B: Reading. C: Total deflection. D: Mean total deflection.

Date: March 2d, 1909. Date: February 20th, 1909. l = 12 ft.; l = 12 ft.; b (mean) = 6.56 in.; b (mean) = 6.22 in.; h (mean) = 15.62 in.; h (mean) = 15.62 in.; c = 7.81 in. c = 7.81 in. Time = 1 hr. Time = 33 min.

========================================================================= P DEFLECTION, IN INCHES. P DEFLECTION, IN INCHES. No. - - - A B C B C D A B C B C D - - - - 1 0 1.84 0 1.71 0 0 0 1.69 0 1.73 0 0 2 2,000 1.88 0.04 1.74 0.03 0.035 2,000 1.72 0.03 1.77 0.04 0.035 3 4,000 1.92 0.08 1.79 0.08 0.080 4,000 1.76 0.07 1.80 0.07 0.070 4 6,000 1.96 0.12 1.81 0.10 0.110 6,000 1.80 0.11 1.84 0.11 0.110 5 8,000 2.00 0.16 1.85 0.14 0.150 8,000 1.84 0.15 1.87 0.14 0.145 6 10,000 2.03 0.19 1.89 0.18 0.185 10,000 1.88 0.19 1.92 0.19 0.190 7 12,000 2.06 0.22 1.93 0.22 0.220 12,000 1.91 0.22 1.95 0.22 0.220 8 14,000 2.11 0.27 1.95 0.24 0.255 14,000 1.95 0.26 2.00 0.27 0.265 9 16,000 2.14 0.30 1.99 0.28 0.290 16,000 1.99 0.30 2.03 0.30 0.300 10 18,000 2.18 0.34 2.03 0.32 0.330 18,000 2.03 0.34 2.06 0.33 0.335 11 20,000 2.22 0.38 2.05 0.34 0.360 20,000 2.07 0.38 2.11 0.38 0.380 12 22,000 2.25 0.41 2.10 0.39 0.400 22,000 2.11 0.42 2.16 0.43 0.425 13 24,000 2.29 0.45 2.13 0.42 0.435 24,000 2.15 0.46 2.20 0.47 0.465 14 26,000 2.32 0.48 2.17 0.46 0.470 26,000 2.19 0.50 2.24 0.51 0.505 15 28,000 2.36 0.52 2.21 0.50 0.510 28,000 2.23 0.54 2.28 0.55 0.545 16 30,000 2.40 0.56 2.25 0.54 0.550 30,000 2.27 0.58 2.33 0.60 0.590 17 32,000 2.43 0.59 2.29 0.58 0.585 32,000 2.32 0.63 2.37 0.64 0.635 18 34,000 2.47 0.63 2.32 0.61 0.620 34,000 2.36 0.67 2.42 0.69 0.680 19 36,000 2.51 0.67 2.37 0.66 0.665 36,000 20 38,000 2.56 0.72 2.41 0.70 0.710 27,000 lb., First Crack; 28,000 lb., First Crack; 51,900 lb., Failed. 49,000 lb., Failed. At Elastic Limit: Load, 34,000 lb.; At Elastic Limit: Load, 20,000 lb.; deflection, 0.62 in.; deflection, 0.38 in.; S, 4,580 lb. S, 2,845 lb. Maximum: Load, 51,900 lb.; Maximum: Load, 49,000 lb.; deflection,.....; deflection,.....; S, 6,985 lb. S, 6,970 lb. E = 1,637,000 lb. E = 1,658,000 lb. =========================================================================

THE END