VITRIFIED BRICK PAVEMENTS FOR COUNTRY ROADS. 29 



and sand. The grout shall be mixed in batches containing not more than one 

 sack of cement in a box about five (5) feet long, thirty (30) inches wide, and 

 fourteen (14) inches deep, resting on legs of different lengths, so that the mix- 

 ture will readily flow to the lowest corner of the box. The sand and cement 

 shall be thoroughly mixed dry. Sufficient clean water shall then be admixed 

 to produce a grout of a consistency about equal to that of ordinary cream for 

 the first application and of a slightly thicker consistency for subsequent ap- 

 plications. From the time the water is added to the mixture until all of the 

 grout is removed from the box, the mixture must be constantly well stirred 

 with mortar hoes. The grout shall be removed from the box with scoop shovels 

 and applied to the brick in front of men supplied with push brooms, who shall 

 rapidly sweep it lengthwise of the brick into the joints until the joints are 

 practically filled. After the first application has been made and the grout 

 has settled into the joints, and before initial set has taken place, the unfilled 

 portion of the joints shall be filled with the thicker grout, and, if necessary, 

 refilled until the joints remain full to the top. After this has been done the 

 pavement shall be finished to a smooth surface, free from any surplus grout, 

 with a squeegee, which shall be worked over the brick at an angle of about 

 forty-five (45) degrees with the curb. The pavement shall have been thor- 

 oughly sprinkled before the first application of grout is made, and shall be kept 

 moist by means of gentle sprinkling until the grout is spread. The top surface, 

 sides, and ends of the brick shall be thoroughly clean at the time the work of 

 filling the joints is done. 



Immediately after the grout has taken its initial set the pavement shall be 

 covered with a one (1) inch layer of sand or earth. This layer, immediately 

 after it is placed on the pavement, shall be thoroughly wet by sprinkling and 

 shall be kept wet by sprinkling for at least the five (5) following days. It shall 

 remain on the pavement for at least ten (10) days and shall be removed before 

 traffic is permitted upon the pavement. During this period of ten (10) days or 

 longer, as the engineer may require on account of weather conditions, no traffic 

 shall be allowed upon and no materials shall be placed upon the pavement. 



Expansion cushion. 1 — An expansion cushion four (4) inches in depth and of 

 the thickness indicated on the plans shall be constructed along each curb as 

 follows : Suitable provision for the cushion shall be made at the time the brick 

 are laid by setting boards of the proper width and thickness on edge in proper 

 position along the curb. After the brick have been laid, rolled, and grouted, 

 and the grout has well set, the boards shall be carefully removed, so as not to 

 damage the curb or the brick pavement, and the spaces which they occupied 

 shall be filled with blown-oil asphalt heated to a temperature of not less than 

 three hundred (300) degrees Fahrenheit and not more than four hundred (400) 

 degrees Fahrenheit. 



ALTERNATE SPECIFICATIONS. 



SEPARATE CONCRETE CURBS. 



Where the plans call for concrete curbs separate from the foundation they 

 shall be constructed before the subgrade is finally completed and shall have 

 the cross section shown on the plans. Such curbs shall be constructed in sec- 

 tions not less than six (6) feet and not more than twelve (12) feet in length 

 and shall be true to grade and alignment. 



1 Instead of making a poured joint, as above described, the cushion may be constructed 

 of some of the specially prepared expansion-joint materials, subject to the approval of 

 the engineer as to the material and method of construction. 



