285. Ingredients Required For One Cubic Yard Of Mortar

The character of the ingredients used in making cement mortar varies so much that it is difficult to accurately determine the quantities of materials required for a proposed mortar except by experimenting with the materials that are to be employed. It has been shown that the weights per cubic foot of both cement and sand vary greatly according to the conditions of packing, the moisture, etc. The percentage of voids in the sand is one of the most important variations affecting the amount of mortar made with certain materials mixed in given proportions. The consistency of the mortar also has a marked effect, and different cements show a considerable variation in the volume of mortar that a given weight will yield. In any general treatment of the question, then, we may expect only approximate results, and the tables given in this connection must be considered in this light.

286. Results Of Experiments

The tests from which Tables 60 and 61 were derived, were made with a natural sand weighing about one hundred pounds to the cubic foot, dry, and having about three-eighths of the bulk voids. The grains varied in size from 0.01 in. to 0.1 in. in diameter with a few grains out-side of these limits. The consistency of the mortar was such that when struck with the shovel blade the moisture would glisten on the smooth surface thus formed. In the experiments the proportions were determined by weight, and the results for proportions by volume were deduced from them. The results for neat natural cement mortar and for the natural cement mortars containing more than four parts sand by weight were derived by analogy.

1 Portions of this article were contributed to "Municipal Engineering" and appeared in that magazine, Feb., 1899.

Table 60. Ingredients Required For One Cubic Yard Of Mortar, Portland Cement

Sand Weighs about 100 lbs. per Cubic Foot. Voids three-eighths of volume.

Sand to 1 of Cement.

Parts

Proportions by Weight, Dry Sand and Cement.

Proportions by Volume Dry Loose Sand to Packed Cement,

Packed Cement Assumed at 104 lbs. per Cu. Ft. or 380 lbs. per Bbl. of 3.65 Cu. Ft.

Proportions by Volume Dry Loose Sand to Packed Cement, Cement Assumed at 114 lbs. per Cu. Ft. or 380 lbs. per Bbl. of 3.33 Cu. Ft.

Proportions by Volume Dry Loose Sand to Loose Cement, Loose Cement Assumed at 85 lbs. per Cu. Ft.

Cement.

Sand Cu Yd.

Cement.

Sand Cu. Yd.

Cement.

Sand Cu. Yd.

Cement.

Sand Cu Yd.

Pounds.

Bbls. of

380# Net.

Pounds.

Bbls. of

380# Net.

Pounds.

Bbls. of

380# Net.

Pounds.

Bbls. of

380 Net.

a

b

c

d

e

f

g

h

i

j

k

l

m

0

2810

7.40

0.00

2810

7.40

0.00

2810

7.40

0.00

2810

7.40

0.00

1

1555

4.08

0.57

1585

4.17

0.56

1640

4.32

0.54

1440

3.79

0.64

2

1050

2.76

0.78

1080

2.84

0.77

1140

3.00

0.74

930

2.45

0.81

3

760

2.00

0.84

785

2.06

0.84

850

2.24

0.82

660

1.74

0.87

4

600

1.58

0.88

615

1.62

0.88

665

1.75

0.87

515

1.36

0.90

5

490

1.29

0.91

505

1.33

0.90

550

1.45

0.89

425

1.12

0.92

6

420

1.10

0.93

435

1.14

• • • •

470

1.24

0.91

7

410

1.08

0.93

Table 61. Ingredients Required For One Cubic Yard Of Mortar, Natural Cement

Sand Weighs about 100 lbs. per Cubic Foot. Voids three-eighths of volume.

Pakts Sand to 1 of Cement.

Proportions by Weight, Dry Sand and Cement.

Proportions by Volume Dry Loose Sand to Packed Cement, Cement Assumed at 71 # per Cubic Foot or 265# Net per Bbl.

Proportions by Volume Dry Loose Sand to Packed Cement, Packed Cement Assumed at 75# per Cu. Ft. or 280# Net per Bbl.

Proportions by Volume Dry Loose Sand to Packed Cement, Cement Assumed 80# per Cu. Ft. or 300# Net per Bbl.

Proportions by Volume Dry Loose Sand to Loose Cement, Loose Cement Assumed at 60# per Cubic Foot.

Cement.

Cement.

Cement.

Cement.

Cement.

Pounds.

Bbls.

of 265# Net.

Bbls. of

280# Net.

Bbls. of

300# Net.

Sand, Cubic Yard.

Pounds.

Bbls. of

265# Net.

Sand, Cubic Yard.

Pounds.

Bbls. of

280# Net.

Sand, Cubic Yard.

Pounds.

Bbls.

of 300# Net.

Sand, Cubic Yard.

Pounds.

Bbls. of 265# Net.

Bbls. of 280# Net.

Bbls. of 300# Net.

Sand, Cubic Yard.

a

b

c

d

e

f

g

h

i

j

k

l

m

n

o

P

Q

r

s

t

0

2210

8.45

8.00

7.47

0.00

2240

8.45

0.00

2240

8.00

0.00

2240

7.47

0.00

2240

8.45

8 00

7.47

0.00

1

1380

5.21

4.93

4.60

0.51

1180

4.45

0.61

1210

4.32

0.60

1250

4.17

0.68

1080

4.08

386

3.60

0.67

2

970

3.66

3.46

3.23

0.72

750

2.83

0.78

780

2.79

0.77

825

2.75

0.76

660

2.49

2.36

2.20

081

3

720

2.72

2.57

2.40

0.80

540

2.04

0.85

570

2.03

0.84

600

2.00

0.83

470

1.77

1.68

1.57

0.87

4

570

2.15

2.03

1.90

0.84

425

1.60

0.89

450

1.60

0.88

470

1.57

0.87

...

...

...

...

...

5

470

1.77

1.68

1.57

0.87

...

...

...

...

...

...

390

1.30

0.90

...

...

...

...

...

6

400

1.51

1.43

1.33

0.89

...

...

...

...

...

...

...

...

...

...

...

...

...

...