SPECIFICATIONS FOR REINFORCED As an example of the manner in which a set of specifications should be drawn up for rein forced concrete work, the Trussed Concrete Steel Company furnish the following form: General— It is the intention of these specifications to include all that is considered best in theory and practice. Special attention must be given in this construction to the quality of labor, material, and character of workmanship.
Bidders must be thoroughly experienced in this class of work, and must have carried through successfully building operations of large and responsible character.
Parties submitting proposals must furnish drawings, indi cating their method of calculation, the arrangement and nature of the steel reinforcement for the various struc tural members indicated ; and no proposition will be con sidered without such calculations and drawings. It is understood furthermore that no system of reinforced concrete construction will be considered which has not been approved by the building departments of all the principal cities of the United States which have studied reinforced concrete and have embodied conditions gov erning its use in their Building Code—namely, New York, Philadelphia, Washington, Cleveland, and St. Louis.
Dimensions of beams, columns, slabs, and other struc tures indicated on drawings 'shall be considered a minimum.
All materials rejected for this work must be imme diately removed from the vicinity. Samples of all ma terials must be submitted and approved by the architect before same are used.
Cement 1. All cement shall be tested.
2. The contractor shall notify the engineer-in-charge as soon as each car of cement is placed, so that the sam ples may be taken therefrom without delay.
3. In order to allow ample time for inspecting and testing, the cement must 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 identifica tion of each carload.
5. Every facility shall be provided by the Contractor
and a period of at least fourteen days allowed for the inspection and necessary tests.
6. Cement shall be delivered in suitable bags with the brand and name of manufacturer plainly marked thereon.
7. Cement failing to meet the seven-day require ments, may be held awaiting the results of the twenty eight days tests before rejection.
8. All tests shall be made in accordance with the methods proposed by the Committee of Uniform Tests of Cement of the American Society for Testing Materials, presented to the Society, January 21, 1903, and amended January 20, 1904, with all subsequent amendments thereto.
9. The acceptance or rejection shall be based on the following requirements: I. The term "Portland Cement" 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 three per cent has been made subsequent to calcination.
II. The specific gravity of the cement thoroughly dried at 100 degrees C. (212 degrees F.) shall be not less than 3.10.
III. All of the cement shall pass through a No. 50 sieve. It shall leave by weight a residue of not more than seven per cent on a No. 100 sieve and not more than twenty-two (22) per cent on a No. 200 sieve.
IV. It shall develop initial set in not less than forty minutes, but must develop hard or final set in not less than two hours, nor more than ten hours.
V. The minimum requirements for tensile strength for briquettes, one inch square in section, shall be as given below and shall show no retrogression in strength within the periods specified.
Neat Cement Age-24 hours 150 lbs in moist air Age— 7 days 450 lbs. 1 day in moist air, 6 days in water Age-28 days 650 lbs. 1 day in moist air, 27 days in water One Part Cement, Three Parts Standard Sand Age— 7 days 160 lbs. 1 day in moist air, G days in water Age-28 days 250 lbs. 1 day in moist air, 27 days in water.