BEICK ROADS. 31 



shovels or by some other means approved by the engineer, and when completed 

 shall not vary more than one-half d) inch from the proper shape and grade, 

 as shown on the plans and profiles. The concrete base shall be kept wet by 

 sprinkling with water during the first four (4) days after it is laid. No hauling 

 over it or rolling or tamping of brick upon it will be permitted for seven (7) 

 days after it is placed, and during this time it shall be properly protected from 

 injury. Concrete shall not be mixed when the temperature of any of the ma- 

 terials is less than thirty -five (35) degrees Fahrenheit. Concrete shall not 

 be used after it has begun to show evidence of setting, and no concrete which 

 has once set shall be used as material for mixing a new batch. 



Curbs. — Concrete curbs shall be built on the base as shown on the plans. The 

 concrete shall be composed of the following materials, by volume: One (1) part 

 of cement, one and one-half yli) parts of sand, three (3) parts of gravel or 

 crushed stone, and water. The materials shall be thoroughly mixed in a ma- 

 chine mixer of the batch type or by hand. If the mixing is done by hand, it 

 shall be done upon a water-tight platform with raised edges, in such manner 

 as to insure thorough mixing of the materials and to meet the approval of the 

 engineer. The concrete for the curb shall be placed upon the base before the 

 concrete of either the curb or the base has taken its initial set, and care shall 

 be taken, such as roughening the concrete of the base and tamping the concrete 

 of the curb, to insure that the curb will be firmly bonded to the base. The 

 concrete shall be well tamped and spaded along the forms, so that when they 

 are removed there will be no open and porous places on the sides of the curb. 

 The top surface of the curb shall be floated or troweled to a smooth finish. The 

 forms for the curb shall be smooth, clean, free from warp, and of sufficient 

 strength to resist springing out of shape. They shall be well staked and 

 braced, and the top edges shall be at the same height and set true to line. 

 To protect the curb from drying out too rapidly it shall, within twelve (12) 

 hours after it is placed, be covered with gunny cloth, which shall be kept wet 

 for five (5) days. 



Sand bedding ^ — Upon the base shall be spread a bedding of sand such that it 

 will have a uniform depth of approximately one and one-half (li) inches when 

 compacted. The base shall be thoroughly clean at the time the bedding is 

 spread. The bedding shall be carefully shaped to a true cross section of the 

 roadway by means of a template having a steel-faced edge, and so fitted as to 

 be readily drawn on the curb. After the bedding is so shaped, it shall be rolled 

 with a hand roller until the material composing it is well compacted. The 

 depressions formed by rolling shall be filled and the surface of the bedding 

 trued up with the template and rolled again. This operation of filling depres- 

 sions, truing np with template, and rolling shall be repeated as often as is 

 necessary to secure a well-compacted bedding true to grade and to the required 

 cross section. The rolling shall be done with a hand roller not less than twenty- 

 four (24) inches in diameter, not less than twenty-four (24) inches in width, 

 and weighing not less than ten (10) pounds per inch of width. 



Laying brick. — Upon the bedding, prepared as above described, the brick 

 shall be laid on edge from curb to curb in straight courses at right angles to 

 the curb, with the lug sides all in the same direction. The brick shall be laid 

 so that the lugs of the brick in one course will touch the brick in the adjoining 



1 If a dry-mortar bedding is to be used substitute the following : 



Dry-mortar tedding. — Upon the base shall be spread a dry-mortar bedding composed of 

 1 part of Portland cement to 5 parts of sand thoroughly mixed. The dry mortar shall be 

 spread in such quantity as to give an average depth of approximately 1 inch when com- 

 pacted. The base shall be thoroughly clean at the time the bedding is spread, etc. 



