. Bulletin of the Department of Agriculture. Agriculture; Agriculture. SAMPLING AND TESTING HIGHWAY MATERIALS. 27 (55) Immediately after mixing, the standard mortar shall be placed in the molds, pressed firmly with the thumbs, and smoothed off with a trowel without ramming. Additional mortar shall be heaped above the mold, and smoothed off with a trowel; the trowel shall be drawn over the mold in such a manner as to exert a moderate pressure on the material. The mold shall then be turned over and the operation of heaping, thumbing, and smoothing off Fig. 13.—Form of briqustte a
. Bulletin of the Department of Agriculture. Agriculture; Agriculture. SAMPLING AND TESTING HIGHWAY MATERIALS. 27 (55) Immediately after mixing, the standard mortar shall be placed in the molds, pressed firmly with the thumbs, and smoothed off with a trowel without ramming. Additional mortar shall be heaped above the mold, and smoothed off with a trowel; the trowel shall be drawn over the mold in such a manner as to exert a moderate pressure on the material. The mold shall then be turned over and the operation of heaping, thumbing, and smoothing off Fig. 13.—Form of briqustte as recommended by the committee on uniform tests of cement of the American Society of Civil Engineers. (56) Tests shall be made with any standard machine. The briquettes shall be tested as soon as they are removed from the water. The bearing surfaces of the clips and briquettes shall be free from grains of sand or dirt. The briquettes shall be carefully centered and the load applied continuously at the rate of 600 pounds per minute. (57) Testing machines should be frequently calibrated in order to determine their accuracy. (58) Briquettes that are manifestly faulty, or which give strengths differing more than 15 per cent from the average value of all tests pieces made from the same sample. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original United States. Dept. of Agriculture. [Washington, D. C. ?] : The Dept. : Supt. of Docs. , G. P. O.
Size: 1488px × 1678px
Photo credit: © Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauth, bookcentury1900, bookdecade1910, booksubjectagriculture
