All operations in connection with excavations necessary for the laying of the sewer pipe and the disposal of all excavated material shall be made in accordance with requirements of the City Engineer, and in accordance with Item 603 and 604 of the Standard Specifications of the State of Ohio, Department of Transportation, latest edition.
All trenches, unless otherwise directed by the Engineer, shall be excavated to the depth shown on the profiles and shall be of sufficient width at both top and bottom so as to permit the proper laying of the sewer pipe, and also the sheeting and shoring of the trench, when necessary.
Except as otherwise provided, all trenches and any cavities caused by the owners' operations outside of the prescribed limits of the trenches, shall be backfilled, as soon as practicable after the pipe has been laid, with suitable material which has been excavated from the site and which shall be selected for the purpose.
The earth backfill shall be placed in horizontal layers not over eight inches in thickness and each layer shall be thoroughly tamped. Under favorable conditions, when allowed by the City Engineer, the earth backfill may be placed in the trench without being tamped in horizontal layers but the trench shall be flooded with water and "puddled" so that a suitable settlement of the backfill materials may be obtained. The upper eighteen inches of the trench shall be backfilled with No. 6 or No. 7 limestone properly compacted, unless otherwise directed by the City Engineer.
Backfilling shall not be made in freezing weather except by permission of the Engineer, nor shall it be made with frozen materials, nor when the material already in the trench is frozen. All materials used for backfilling shall be free from perishable and objectionable substances, and shall contain no stones larger than three inches in diameter.
The No. 6 limestone bed on which the pipes are to be laid shall be brought around the side of the pipe to the spring line. Special care shall be taken in placing and tamping selected earth material around the balance of the pipe not embedded in the limestone, and to a depth of twelve inches over the top of the pipe.
No slag, cinders, rubbish, rocks, boulders, shales or other objectionable material shall be used to backfill against the pipe or in any part of the trench where in the opinion of the Engineer it will be injurious to the work.
The owner shall maintain all excavations in good order so as not to hinder or injure the pipe laying or other work, shall take reasonable precautions to prevent movement of the sides of such excavations, and shall remove at his own expense any material sliding into the excavations.
Should the materials excavated from the trench be unsuitable for backfilling purposes to such an extent that the quantity of suitable materials is insufficient to complete the backfilling around and over the completed sewer, the owner shall satisfactorily dispose of such unsuitable material and shall obtain suitable earth, gravel or stone, acceptable to the City Engineer, and use the same for backfilling to the lines and grades shown or given.
Excavated material shall be disposed of, so far as possible, in backfilling and grading to the lines and grades shown or given. Any excess material not required for backfilling or which is not suitable for such purpose shall be promptly removed and satisfactorily disposed of by the owner.
All nonreinforced concrete pipe shall be of the best quality of concrete, free from imperfections of any kind, and shall have a smooth dense finish. The pipe shall be of the bell and spigot type, and shall be cast outside the trench, in forms true to shape and dimensions, rigid, smooth and substantially watertight. All nonreinforced concrete pipe shall be made by or under the direct supervision of some well-known and reputable manufacturer whose type of construction has been used commercially for similar installations for a period of at least three years. All pipe shall be at least four feet in length.
All nonreinforced concrete sewer pipe shall be Extra-Strength Plain Cement Concrete Pipe, classified in State of Ohio, Department of Transportation Specifications as (706.01 Class 3).
As soon as the forms are removed from the pipe it shall be protected from the sun and wind for forty-eight hours. No pipe shall be laid until it has cured for at least fourteen days.
All pipes shall be laid true to line and grade with the bell end up, and with firm and even bearing upon a proper and dry foundation, shaped to receive the pipe. Care shall be taken to secure closeness of joints and smoothness and continuity of invert. The trench, in case of construction in rock, shall be made to conform to the general dimensions required and the subgrade shall be brought to the required elevation by using well compacted slag, gravel or crushed stone.
The sides and bottoms of the sewers shall be supported by compacting these materials in place so as to insure an even bearing for the pipe. Particular care shall be taken that the pipes are not permitted to rest upon or against either solid rock or projecting portions of rock.
The mortar for pipe joints shall be composed of Portland cement of a brand which has been upon the market and used successfully in engineering work and the sand used in the mortar shall be clean, silicious sand and shall be free from injurious amounts of organic impurities. The sand shall be well-graded from coarse to fine.
All concrete pipe shall be laid with mortar joints. Care shall be taken to see that the space between the pipe and socket is as uniform as possible. The joints shall be made with a gasket of the best quality jute or hemp, as approved by the Engineer, and cement mortar. The gasket shall be carefully coiled and thoroughly saturated with neat Portland cement and water and then inserted between the bell and spigot and carefully calked. The gasket shall be in one continuous piece for each joint, and of such thickness as will bring the pipe to the required relative position. The remainder of the joint shall be filled with mortar well pressed into place, after which the joints shall be beveled off with the mortar for a distance of at least two inches from the outer edge of the bell. No surplus mortar or other foreign substances shall project into the pipes from the joints. The joints shall be properly cleaned by a suitable scraper or follower before the mortar has become hardened. In no case shall water be allowed to rise in or about the pipe before the mortar on the joints has thoroughly set.
The contractor shall remove all bulkheads which have been left in place in existing sewers or existing structures, and shall make proper connections to these sewers and structures in the manner and at the locations shown. Also, he shall make the necessary conduit, pipe line and sewer connections at the several points. (Ord. 1961-3. Passed 7-31-61.)