Adopted by the Society, November 14th, 1904.

General Observations

1. These remarks have been prepared with a view of pointing out the pertinent features of the various requirements and the precautions to be observed in the interpretation of the results of the tests.

2. The Committee would suggest that the acceptance or rejection under these specifications be based on tests made by an experienced person having the proper means for making the tests.

Specific Gravity

3. Specific gravity is useful in detecting adulteration or underburning. The results of tests of specific gravity are not necessarily conclusive as an indication of the quality of a cement, but when in combination with the results of other tests may afford valuable indications.

Fineness

4. The sieves should be kept thoroughly dry.

Time Of Setting

5. Great care should be exercised to maintain the test pieces under as uniform conditions as possible. A sudden change or wide range of temperature in the room in which the tests are made, a very dry or humid atmosphere, and other irregularities vitally affect the rate of setting.

Tensile Strength

6. Each consumer must fix the minimum requirements for tensile strength to suit his own conditions. They shall, however, be within the limits stated.

Constancy Of Volume

7. The tests for constancy of volume are divided into two classes, the first normal, the second accelerated. The latter should be regarded as a precautionary test only, and not infallible. So many conditions enter into the making and interpreting of it that it should be used with extreme care.

8. In making the pats the greatest care should be exercised to avoid initial strains due to moulding or to too rapid drying-out during the first twenty-four hours. The pats should be preserved under the most uniform conditions possible, and rapid changes of temperature should be avoided.

9. The failure to meet the requirements of the accelerated tests need not be sufficient cause for rejection. The cement may, however, be held for twenty-eight days, and a retest made at the end of that period. Failure to meet the requirements at this time should be considered sufficient cause for rejection, although in the present state of our knowledge it cannot be said that such failure necessarily indicates unsoundness, nor can the cement be considered entirely satisfactory simply because it passes the tests.

General Conditions

1. All cement shall be inspected.

2. Cement may be inspected either at the place of manufacture or on the work.

3. In order to allow ample time for inspecting and testing, the cement should be stored in a suitable weather-tight building having the floor properly blocked or raised from the ground.

4. The cement shall be stored in such a manner as to permit easy access for proper inspection and identification of each shipment.

5. Every facility shall be provided by the contractor and a period of at least twelve days allowed for the inspection and necessary tests.

6. Cement shall be delivered in suitable packages with the brand and name of manufacturer plainly marked thereon.

7. A bag of cement shall contain 94 pounds of cement net. Each barrel of Portland cement shall contain 4 bags, and each barrel of natural cement shall contain 3 bags of the above net weight.

8. Cement failing to meet the seven-day requirements may be held awaiting the results of the twenty-eight day tests before rejection.

9. All tests shall be made in accordance with the methods proposed by the Committee on Uniform Tests of Cement of the American Society of Civil Engineers, presented to the Society January 21, 1903, and amended January 20, 1904, with all subsequent amendments thereto.

10. The acceptance or rejection shall be based on the following requirements:

Natural Cement

11. Definition

This term shall be applied to the finely pulverized product resulting from the calcination of an argillaceous limestone at a temperature only sufficient to drive off the carbonic acid gas.

Specific Gravity

12. The specific gravity of the cement thoroughly dried at 100°C. shall be not less than 2.8.

Fineness

13. It shall leave by weight a residue of not more than 10 per cent on the No. 100, and 30 per cent on the No. 200 sieve.

Time Of Setting

14. It shall develop initial set in not less than ten minutes, and hard set in not les3 than thirty minutes, nor more than three hours.

Tensile Strength

15. The minimum requirements for tensile strength for briquettes one inch square in cross section shall be within the following limits, and shall show no retrogression in strength within the periods specified:1

Age Neat Cement Strength

24 hours in moist air.............. 50—100 lbs.

7 days (1 day in moist air, 6 days in water) . . . 100—200 " 28 days (1 day in moist air, 27 days in water) . . 200—300 "

One Part Cement, Three Parts Standard Sand

7 days (1 day in moist air, 6 days in water) ... 25— 75 lbs. 28 days (1 day in moist air, 27 days in water) . . 75—150 "

Constancy Of Volume

16. Pats of neat cement about three inches in diameter, one-half inch thick at centre, tapering to a thin edge, shall be kept in moist air for a period of twenty-four hours.

(a) A pat is then kept in air at normal temperature.

(b) Another is kept in water maintained as near 70° F. as practicable.

17. These pats are observed at intervals for at least 28 days, and, to satisfactorily pass the tests, should remain firm and hard and show no signs of distortion, checking, cracking, or disintegrating.

Portland Cement

18. Definition

This term is applied to the finely pulverized product resulting from the calcination to incipient fusion of an intimate mixture of properly proportioned argillaceous and calcareous materials, and to which no addition greater than 3 per cent has been made subsequent to calcination.

For example, the minimum requirement for the twenty-four hour neat cement test should be some specified value within the limits of 50 and 100 pounds, and so on for each period stated.

Specific Gravity

19. The specific gravity of the cement, thoroughly dried, at 100° C, shall be not less than 3.10.

Fineness

20. It shall leave by weight a residue of not more than 8 per cent on the No. 100, and not more than 25 per cent on the No. 200 sieve.

Time Of Setting

21. It shall develop initial set in not less than thirty minutes, but must develop hard set in not less than one hour, nor more than ten hours.

Tensile Strength

22. The minimum requirements for tensile strength for briquettes one inch square in section shall be within the following limits, and shall show no retrogression in strength within the periods specified:1

Age Neat Cement Strength

24 hours in moist air............. 150—200 lbs.

7 days (1 day in moist air, 6 days in water) . . 450—550 "

28 days (1 day in moist air, 27 days in water) . . 550—650 "

One Part Cement, Three Parts Sand

7 days (1 day in moist air, 6 days in water) . . 150—200 lbs.

28 days (1 day in moist air, 27 days in water) . . 200—300 "

Constancy Of Volume

23. Pats of neat cement about three inches in diameter, one-half inch thick at the centre, and tapering to a thin edge, shall be kept in moist air for a period of twenty-four hours.

(d) A pat is then kept in air at normal temperature and observed at intervals for at least 28 days.

(b) Another pat is kept in water maintained as near 70° F. as practicable, and observed at intervals for at least 28 days.

(c) A third pat is exposed in any convenient way in an atmosphere of steam, above boiling water, in a loosely closed vessel for five hours.

24. These pats, to satisfactorily pass the requirements, shall remain firm and hard and show no signs of distortion, checking, cracking, or disintegrating.

1 For example, the minimum requirement for the twenty-four hour neat cement test should be some specified value within the limits of 150 and 200 pounds, and so on for each period stated.

Sulphuric Acid And Magnesia

25. The cement shall not contain more than 1.75 per cent of anhydrous sulphuric acid (S03), nor more than 4 per cent of magnesia (MgO).

Submitted on behalf of the Committee.

George F. Swain, Chairman. George S. Webster, Vice-Chairman, Richard L. Humphrey, Secretary.

Committee

George F. Swain. George S. Webster. Richard L. Humphrey. Booth, Garrett & Blair. C. W. Boynton. Spencer Cosby. A. W. Dow. L. Henry Dumary. A. F. Gerstell. Edward M. Hagar. W. H. Harding. Olaf Hoff.

Lathbury & Spackman. Robert W. Lesley. F H. Lewis.

John B. Lober. Andreas Lundteigen. Charles F. McKenna. W. W. Maclay. Charles A. Matcham. Spencer B. Newberry. J. M. Porter. Joseph T. Richards. Clifford Richardson. L. C. Sabin. Harry J. Seaman. S. S. Voorhees. W. S. Eames. H. G. Kelly.