SPECIFICATIONS FOB NONBITUMINOUS ROAD MATERIALS. 21 



be specified by the purchaser. At least 10 days from the tiiae of sam- 

 pling shall be allowed for the completion of the 7-day test ; and at least 

 31 days shall be allowed for the completion of the 28-day test. The 28-day 

 test shall be waived only when specifically ordered. 



V. REJECTION. 



Bejectlon. 



(12) The cement may be rejected if it fails to meet any of the re- 

 quirements of these specifications. 



(13) Cement shall not be rejected on account of failure to meet the 

 fineness requirement if, upon retest after drying at 100° C. (212° F.) 

 for one hour it meets this requirement. 



(14) Cement failing to meet the test for soundness in steam may be 

 accepted if it passes a retest using a new sample at any time within 28 

 days thereafter. 



(15) Packages varying more than 5 per cent from the specified weight 

 may be rejected ; and if the average weight of packages in any ship- 

 ment, as shown by weighing 50 packages taken at random, is less than 

 that specified, the entire shipment may be rejected. 



The cement shall be tested in accordance with the following methods : Methods of 

 Tests for Portland cement, A. S. T. M. Standard, C9-17. Testing. 



This is the United States Government specification for Portland 

 cement, as described in Bureau of Standards Circular No. 33. It 

 is also Standard Specification C9-17 of the American Society for 

 Testing Materials. It is intended to apply wherever Portland 

 cement is used. 



SPECIFICATION Br-1. 



Vitrified Paving Brick, CusMon Sand, and Grouting Sand for Brick 

 Pavement. 



VETBIFIED PAVING BRICK. 



All brick shall be of a size commercially known as four-Inch brick. General. 

 They shall be thoroughly annealed, tough and durable, regular in size and 

 shape, and evenly burned. When broken, the brick shall show a dense, 

 stonelike body, free from lime, air pockets, cracks, or marked laminations. 

 Kiln marks shall not exceed -re of an inch, and the wearing surface shall 

 show but slight kiln marks. 



Representative samples of the brick shall meet the following require- Battler Test. 

 ments when subjected to the rattler test : 



Average loss by abrasion on one or more samples, not more than 22 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 24 per cent loss. 

 A maximum of three tests may be used as a basis for rejection. 

 The brick shall meet the following requirements : Dimensions. 



Inches. 



Length 81 to 94 



Width Si to 31 



Depth 31 to 4i 



Variations among brick from a single plant shall not exceed the fol- 

 lowing limits : 



Inch. 



Variation in length i 



Variation in width | 



Variation in depth | 



