SPECIFICATIONS FOR NONBITUMINOUS ROAD MATERIALS. 25 
SPECIFICATION R-1. 
Granite Block, Gravel, and Sand for Stone-Block Pavement. 
STONE BLOCK. 
The stone block shall be of granite of medium-sized grain, showing an 
even distribution of constituent minerals. They shall be of uniform qual- 
ity and texture throughout, and free from seams, scales, or disintegrated 
material. 
Sample blocks shall meet the following requirement: 
IMAGINE NCCE ONE Velie, AONE USS oe te ee ee 8 
IMOUEINTESS MOE WES eae Wal as ee ey Saris asta ieee TF 
The blocks shall meet the following requirements : 
Inches 
BNET ET OTN at OP a ee al aru es =e Sieh, Oy) ad 
SUB Le CONEY BO) an ST er AE a A Se See ee NE 33 to 434 
ADDY) oY) ey Nay i 86 ops a a gE I ed 43 to x 
The stone block 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 those which fail to conform with the general and dimension clauses 
and the following requirements of this specification : 
The blocks shall be so dressed that when laid as specified measurement 
of any joint shall show a width of not more than 4 inch for a depth of 1 
inch, or a width of not more than 1 inch in any part of the joint. 
The wearing surface of the hlocks shall show no depressions more than 
8 inch deep, and the edges and corners shall be unchipped and unbroken. 
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. 
SAND FOR GROUTING. 
The sand shall consist of clean, hard, durable, uncoated stone particles, 
preferably siliceous, free from lumps of clay and all organic matter. 
It shall be well graded from coarse to fine and, when tested by means 
of laboratory screens, Shall meet the following requirements: 
Per cent. 
PASSO PPO mes he Sie y Cmte mn mecmanabensad eA) Sia ARY Pe SMI eee wl A 100 
PASSing wes O-IMESHESTC Yew en Ot SESS a thnel esc e Se s 80 
Passing TOO AMESHUSIE VE, 21 Ol NOT Cine meee es ee ee 10 
Not more than 5 per cent by weight shall be removed by the elutriation 
test. 
When the sand is mixed with Portland cement in the proportions of 1 
part of cement to 8 parts of sand by weight, according to standard meth- 
ods of making 1:3 mortar briquets, the resulting mortar at the age of 7 
and 28 days shall have a tensile strength of at least 75 per cent of that 
developed in the same time by mortar of the same proportions and con- 
sistency, made of the same cement and Ottawa sand. 
Preliminary acceptance samples shall be subjected to both 7 and 28 
day tests, and acceptance based thereupon. ‘Samples.tested during the 
progress of the work will be accepted on the basis of the 7-day test. 
GRAVEL FOR FILLER. 
The gravel shall be composed of clean, hard, durable fragments of rock. 
When tested by means of laboratory screens it shall meet the following 
requirements : 
Per cent. 
JPRS” ein HAS, TAKE) WEI woe ae Oe eee 95 
Rerainedeoney -utcheml 0. sess) Lian feo ee a Se eee 85 
Tests of the physical properties of the block, gravel, and sand shall be 
made in accordance with the following methods: 
1. French coefficient of wear, U. S. Department of Agriculture Bulletin 
347, p. 4. 
2. Toughness, U. S. Department of Agriculture Bulletin: 347, p. 15. 
General. 
Physical 
Properties. 
Dimensions. 
Visual 
Inspection. 
Grading. 
General. 
Grading. 
Mortar Strength 
Test. 
General. 
Grading. 
Methods of 
Testing. 
