SPECIFICATIONS FOR STONE MASONRY.* 



GENERAL. 



i. Standard Specifications. The classification of masonry and the requirements for cement 

 and concrete shall be those adopted by the American Railway Engineering Association. 



Engineer Defined. Where the term "Engineer" is used in these specifications, it refers 



to the cn^iiu >. T actually in charge of the work. 



GENERAL REQUIREMENTS. 



3. Stone. Stone shall be of the kinds designated and shall be hard and durable, of approved 

 quality and shape, free from seams, or other imperfections. Unseasoned stone shall not be used 

 where liable to injury by frost. 



4. Dressing. Dressing shall be the best of the kind specified. 



5. Beds and joints or builds shall be square with each other, and dressed true and out of 

 wind. Hollow beds shall not be permitted. 



6. Stone shall be dressed for laying on the natural bed. In all cases the bed shall not be 

 less than the rise. 



7. Marginal drafts shall be neat and accurate. 



8. Pitching shall be done to true lines and exact batter. 



9. Mortar. Mortar shall be mixed in a suitable box, or in a machine mixer, preferably of 

 the batch type, and shall be kept free from foreign matter. The size of the batch and the pro- 

 portions and the consistency shall be as directed by the engineer. When mixed by hand the sand 

 and cement shall be mixed dry, the requisite amount of water then added and the mixing continued 

 until the cement is uniformly distributed and the mass is uniform in color and homogeneous. 



10. Laying. The arrangement of courses and bond shall be as indicated on the drawings, or 

 as directed by the engineer. Stone shall be laid to exact lines and levels, to give the required bond 

 and thickness of mortar in beds and joints. . 



11. Stone shall be cleansed and dampened before laying. 



12. Stone shall be well bonded, laid on its natural bed and solidly settled into place in a full 

 bed of. mortar. 



13. Stone shall not be dropped or slid over the wall, but shall be placed without jarring stone 

 already laid. 



14. Heavy hammering shall not be allowed on the wall after a course is laid. 



15. Stone becoming loose after the mortar is set shall be relaid with fresh mortar. 



16. Stone shall not be laid in freezing weather, unless directed by the engineer. If laid, 

 it shall be freed from ice, snow or frost by warming; the sand and water used in the mortar shall 

 be heated. 



17. With precaution, a brine may be substituted for the heating of the mortar. The brine 

 shall consist of one pound of salt to eighteen gallons of water, when the temperature is 32 degrees 

 Fahrenheit; for every degree of temperature below 32 degrees Fahrenheit, one ounce of salt shall 

 be added. 



1 8. Pointing. Before the mortar has set in beds and joints, it shall be removed to a depth of 

 not less than one (i) in. Pointing shall not be done until the wall is complete and mortar set; 

 nor when frost is in the stone. 



19 Mortar for pointing shall consist of equal parts of sand, sieved to meet the requirements, 

 and Portland cement. In pointing, the joints shall be wet, and filled with mortar, pounded in 

 with a "set-in" or calking tool and finished with a beading tool the width of a joint, used with a 

 straight-edge. 



BRIDGE AND RETAINING WALL MASONRY ASHLAR STONE. 



20. Bridge and Retaining Wall Masonry. Ashlar Stone. The stone shall be large and 

 well proportioned. Courses shall not be less than fourteen (14) in. or more than thirty (30) in. 

 thick, thickness of courses to diminish regularly from bottom to top. 



21. Dressing. Beds and joints or builds of face stone shall be fine-pointed, so that the 

 mortar layer should not be more than one-half (}) in. thick when the stone is laid. 



22. Joints in face stone shall be full to the square for a depth equal to at least one-half the 

 height of the course, but in no case less than twelve (12) in. 



* Adopted by American Railway Engineering Association. 



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