SPECIFICATIONS FOR NONBITUMINOUS ROAD MATERIALS. 
SPECIFICATION Br-2. 
Vitrified Paving Brick, Cushion Sand, and Grouting Sand for Brick 
Pavement. 
VITRIFIED PAVING BRICK. 
All brick shall be of a size commercially known as * 3-inch brick.’’ 
They shall be thoroughly annealed, tough and durable, regular in size 
and shape, and evenly burned. When broken, the bricks shall show a 
dense, stonelike body, free from lime, air pockets, cracks, or marked 
laminations. Kiln marks shall not exceed #; of an inch, and the wearing 
surface shall show but slight kiln marks. 
Representative samples of the brick shall meet the following require- 
ments when subjected to the rattler test: 
Average loss by abrasion on one or more samples, not more than 26 
per cent. 
Maximum difference in per cent loss by abrasion when more than one 
representative sample is tested, not more than 8 per cent, provided, 
however, that no sample shall show more than 28 per cent loss. 
A maximum of three tests will be used as a basis for rejection. 
The brick shall meet the following requirements: 
Inches. 
ERS 1 ef a ee ae ee Se Seco. 9 
NERY TAGE DY SS ol ga ce re roe a eee hie: A Sok cae I ae 384 to 4 
De pt his see ee ee eae ue eee a a i a Bn ig % to 33 
Variations among brick from a single plant shall not exceed the follow- 
ing limits: 
SVT Ted GT © Tae hed en ae Te eae ea ee ee Z 
VESTN ETUC AY STU SAA UC BS a a ee ee PS 
Varigtionsinid ep ties ss se see Cee os ee Sa ee ere eae Zz 
Only brick with lugs on one side, raised not less than % of an inch 
and not more than of an inch, shall be used. 
The ends of the brick shall have either a semicircular groove with a 
radius of not less than 4 of an inch or more than i of an inch, or a bulge 
of at least 7; of an inch. 
The name or trade-mark of the manufacturer, if shown on the brick, 
shall be recessed and not raised. 
The bricks shall be subjected to inspection subsequent to delivery at 
the place of use, prior to and during laying, in order to cull out and 
reject upon variations from the general and dimensions clauses and 
upon the following grounds: 
All bricks which are broken through, or chipped in such manner that 
neither wearing surface remains substantially intact, or in such manner 
that the lower or bearing surface is reduced in area by more than one- 
eighth. 
All bricks which are cracked to a depth greater than 34 inch on any 
surface, or which are cracked on the wearing surface. 
All bricks which are so offsize or so misshaped, bent, twisted, or kiln 
marked that they will not form a proper surface or align properly with 
other bricks. 
All bricks which are obviously too soft and too poorly vitrified to en- 
dure street wear. 
SAND FOR CUSHION. 
The sand shall pass a 43-inch laboratory screen and shall be well 
graded from coarse to fine. The material removed by the elutriation 
test, consisting chiefly of clay and loam, shall not exceed 5 per cent by 
weight, 
General. 
Rattler Test. 
Dimensions, 
Visual 
Inspection. 
General. 
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