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Designation C 9-21, approved March 31,
<br />Engineering StandardsCommittee.
<br />
<br />1922 as "American "
<br /> Standard , by the American
<br />
<br /> ~)' pACKAGES, .MARKING AND STORAGE. The 'cement shall be delivered in suitable
<br />bags or b2rrels with the brand and name of the manUfacturer plainly marked thereon.
<br />A bag of cement shall Contain ni~zety four;'(94) pound~ net, and will be considered as
<br />equivalent to one (1) cubic foot. A barrel shall contain three hundred seventy-six
<br />(376) pounds net, and will be considered as equIMalsnt to fou~'-(4) cubic feet.
<br />
<br /> The cement shall be stored in such a manner as to permit easy access for
<br />proper inspection and identification .of each shipment and in a suitable weather-tight
<br />building which ~ill. protect the cement from dampness. ~.
<br />
<br /> (c) INSPECTION. Every facility shall be provided, the Superintendent of
<br />Streets for careful sampling and inspection at either the mill or at the site of the
<br />work, as may be specified by him. When a semen (7) day test is required by the
<br />Superintendent of Streets at least ten (10) days from the time of s~mpling shall be
<br />allowed for the completion of the test, and at least thirty-one (31) days shall be
<br />allowed for the completion of the twenty-eight (28) day test. The cement shall be
<br />tested in accordance with the methods hereinafter prescribed. The twenty-eight (28)
<br />day test shall b~ waived only when sgecifically ordered.
<br />
<br /> (d) REJECTION. The cement may be rejected if it fails to meet any of the
<br />requirements of these speciflcatlons.~
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<br /> Cement shall not be rejected on account of ~ailure to meet the fineness
<br />requirement if, upon retest after drying at one h~dred (100) degrees Centigrade for one
<br />hour, it meets this re~ irement.
<br />
<br />it passes
<br />after.
<br />
<br /> Cement failing to meet the test for soundness in steam may be accepted if
<br />a retest using a new sample at any time within twenty-eight (28) days there-
<br />
<br /> Packages varying mo~e than five (8) percent from the specified weight
<br />may be rejected; and if the average weight of packages in any shipment, as ~own by
<br />weighing fifty (80) packages taken at random, is less than that specified, the entire
<br />shipment may be ~eJected.
<br />
<br />Section 2. Sand.
<br />
<br /> All sand shall be clean, hard, durable, uncoated stone particles free from
<br />organic matter and lumps of clay.
<br />
<br /> (a) CONCRETE SAND. Sand f~ all cement and concrete work shall contain not
<br />more than three (3) per cent, b~ weight, of mica; not more than fou~ (4) per cent ~)
<br />weight removale by the elutriation test; not more than six (6) per cent, by weight, ah aL
<br />~ass a sieve having one hundred (100) meshes per linear inch: not less than ninety-five
<br />95) per cent, by weight, shall pass a screen having four (4) meshes per linear inch:
<br />at least fifty (80) per cent but not more than eighty five (85) ~r cent, by weight, ahal
<br />be retained on a sieve having (30) meshes per linear inch.
<br />
<br /> ~hen the sand is mixed with Portland Cement in the proportion of one (1) part
<br />of cement to three (3) parts of sand by weight according to the standard meth~s of
<br />making 1:3 mortar briquettes, tha resulting briquettes at the ages of both seven (7) and
<br />twenty-eight (28) days, when compared with briquettes mixed at the same time in the same
<br />proportions and consistently using the same cement, but with Standard Ottawa Testing
<br />Sand shall show a tensile strength ratio of one hundred (100) per cent. Sand showing a
<br />tensile 'strength of less than one hundred (100) but not less than eighty-five (88) per
<br />cent, will be accepted for use subject to the use of additional cement.
<br />
<br /> The additional proportion of cement re, ired shall be determined by laboratory
<br />tssts and shall be the percentage required to increase the strength ratio to one hundred
<br />(100) per cent.
<br />
<br /> In the absence of the above laboratory tests, and at the option of the
<br />Superinten~ent of Streets only, a field test may be made as follows:
<br />
<br /> Fill an ordinary glass fruit Jar two-third (2-3) or three-fourths (3-4) full of
<br />the sample of sa~d, then add sufficient water to thoroughly wash the sand by vigorous
<br />shaking~He shaking to be done for three (3) minutes, and by holding the Jar in a
<br />vertical position after which it shall be allowed to settle. The indicated sediment
<br />appearing on the top of the well definsd minute grains of sand shall not measure more
<br />than ten (10) per cent of the total after settling for one (1) hour, nor more than five
<br />(5) per cent after settling fer a ~riod of twenty-Four (24) hours.
<br />
<br /> (c) CUSHION SAND. Sand for cushion under concrete work on adobe and other
<br />swelling soils, shall contain not more than ten (10) per cent by weight, of clay and sill
<br />and shall all pass a screen having one-half (~) inch round openings.
<br />
<br />Section 3. Broken Stone or Gravel.
<br />
<br /> (a) BROKEN STONE. Broken stone shall be ~arrled rock, free from loam, clay
<br /> and organic matter, and shall have a specific gravity of not less than two and sixty-flw
<br /> undredths (2.6~). It mhall be uniform in quality and shall contain not more than five
<br /> 5) pev cent, by weight, of pieces having rounded surfaces.
<br />
<br /> (b) GRAVEL. Gravel sh~l co~sist of clean, watt, r-worn pebbles, crushed
<br /> boulders, or both, .and shall be free from organic matter, shale, disintegrated, or soft
<br /> stone, clay, or other deleterious substance.
<br />
<br /> (c) CLASSIFICATION. The maximum length of any one particle of ~avel or
<br /> broken stone passing a screen or ring, shall n~ be greater than fifty (SO)per cent in
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