APPENDIX
III
N O T E S FOR THE INSPECTOR
1.
STICK GAGES. A stick gage c a l i b r a t e d in cubic feet to measure the vol-
ume of grout in an upright cylindrical tank can be made, if none is available
when the equipment is brought to the jobsite. Given: a tank 2-1/2 ft high
and 3 ft in diameter.
The height of the tank, 30 in., divided by 17.7 gives the depth of a cubic foot
of grout in the tank in inches. Each cubic foot of grout fills approximately
1.7 in. of the tank. The stick gage may be made from a piece of 1- by 2-in.
l u m b e r . For ease in reading, the gage should be marked so that the correct
reading for the amount of grout in the tank appears at the rim of the tank
when the tip of the stick touches the grout. If there was 9.0 cu ft of grout in
the tank described in the example, the mark for 9.0 cu ft would be 14.7 in.
above the bottom of the gage. The gage may also be prepared by metering
the water into the sump tank by the cubic foot and marking the gage appro-
priately for each level. If the tank has an outside well for the pump suction
or a bulky agitator, this method of calibration is the most accurate.
THINNING
OR
THICKENING
CEMENT
GROUT.
2.
a.
The quickest way to change a given quantity of cement grout from one
another is by using conversion tables or charts. However, the in-
mix to
spector
should be able to make the necessary computations without hesita-
tion, if
such tables or charts are not available.
b. The first step for controlled thinning or thickening of a given quantity
of grout is to determine the amount of cement it contains. This is done by
dividing the cubic feet of grout by the number of cubic feet of grout obtained
from a one-sack batch of that grout, keeping in mind that a sack of cement in
water has a volume of 0.5 cu ft. Examples:
Find the number of sacks of ce-
ment in 12.6 cu ft of 4:1 grout, 1.5:1 grout, and 0.75:1 grout. In the order
listed, 12.6 is divided by 4.5, by 2.0, and by 1.25, and the sacks of cement in
12.6 cu ft of grout for the three mixes in the same order are 2.8, 6.3, and
40.4.
c. To thin a grout add cubic feet of water equal in number to the number
of sacks of cement in the grout to be thinned multiplied by the difference be-
tween the figures representing the water in the water-cement ratios for the
grout on hand and the mix desired. Example: Find the cubic feet of water
necessary to thin 7.2 cu ft of 1:1 grout to 3:1 grout. The number of sacks of
1.5 or 4.8. The difference between
the figures representing the water in the water-cement ratios of the two
mixes (3:1 and 1:1) is two. Two times 4.8 is 9.6. Therefore, 9.6 cu ft of
water must be added to 7.2 cu ft of 1:1 grout to have 3:1 grout.
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