34 



BULLETIN 12A, U. S. DEPAETMENT OF AGRICULTUEE. 



CONCRETE TILE. 



Concrete tile is made from Portland cement and sand or fine gravel 

 and may be substituted for cla}' tile wherever conditions are such as 

 to make the use of concrete economical. The onl}^ exception to this 

 rule is that where the water a tile is intended to carry contains any 

 considerable quantity of either alkali or acid cla}' is preferable to 

 concrete, because concrete may be destroyed quickly by strong alkali 

 or acid, while these materials do not affect clay tile seriousl3^ Ma- 

 chines for manufacturing concrete tile ma}^ be purchased for from 

 $40 to $100 and may be operated either by hand or bj^ a suitable en- 

 gine. Table 9 shows the size, weight, and quantities of materials re- 

 quired for concrete tile of various diameters, and the following list 

 of suggestions are practically sufficient to serve as a guide in the 

 manufacture of such tiles. 



Table 9. — Concrete tile. 



[Straight tile — concrete mixed in proportion 1:3.] 



Diameter. 



Thick- 



Weight 

 per 

 foot. 



Material re- 

 quired per 100 

 feet. 



Diameter. 



Thick- 

 ness. 



Weight 

 per 

 foot. 



Material re- 

 quired per 100 

 feet. 





Ce- 

 ment. 



Aggre- 

 gate. 



Ce- 

 ment. 



Aggre- 

 gate. 



Inches. 

 4 



Inches. 



i 



a 

 a 



Is 



Pounds. 

 10.6 

 13.1 

 15.3 

 21.3 

 31.2 



Bbls. 



0.67 



.83 



.97 



1.3d 



1.98 



Cu. yds. 



0.30 



.37 



.43 



.60 



.88 



Inches. 

 9 



Inches. 

 IV 



11 



Pounds. 

 38.6 

 42.6 

 46.5 

 50.4 



Bbls. 



2.44 

 2.72 

 2.96 

 3.20 



Cu. yds. 

 1.09 



5 



10 



1.20 



6 



11 



1.31 



7 



12 



1.42 



8 













1. Use a reputable brand of Portland cement known to confonn 

 with some standard specification, such as that of the United States 

 Bureau of Standards, published in their bulletin No. 33. 



2. The sand used as aggregate should be clean and graded in size 

 from fine to coarse, with the coarse grains predominating. For the 

 smaller sizes of pipe all the sand should pass a 5-inch mesh screen, 

 but for the larger sizes it is economical to have the aggregate consist 

 partl}'^ of fine gravel that will pass a ^-inch mesh screen. The X3ro- 

 portion of gravel to sand should not be greater than 2 : 1. 



3. The proportion of cement to aggregate should be about 1:3, but 

 if the sand be inferior in any respect the amount of cement should 

 be increased. 



4. In making the tile, the concrete should be tamped into the forms 

 so that no open or porous spaces are left, and the consistency of the 

 concrete should be such that this can be done with comparative 

 ease. 



