That the concrete is of the proper consistency.
That an accurate account is kept of the number of batches mixed, the same to be recorded on a printed card which will be furnished for that purpose.
That these batch record cards are preserved and filed for future reference.
That in placing the concrete the same will be done in a careful manner, and precautions taken not to allow the concrete bucket to come in contact with the form work.
That care is taken not to jar the form work until the concrete work is hardened.
That in making a bond between old and new work care is taken to thoroughly clean the surface of old concrete (preferably by a jet of steam), and that a thin layer of a 1 to 1 grout is spread to assist in making a good bond.
That the surface of the concrete which is to be bonded to other concrete is left in a rough condition, either by spreading a layer of broken stone over the same, running half the depth of the stone into the green concrete, and leaving the upper half of the stone protruding, or by setting in strips of wood, which, when removed, will form a groove and assist in making a good bond.
That in bonding the spandrel wall with the arch-ring, a groove or ridge is formed on arch-rings running under and with spandrel wall, to prevent water from center filling to run through and down the face of arch-ring, discoloring same.
That in placing dry concrete the same is thoroughly compacted with suitable approved iron tamps.
That in pouring wet concrete the same is thoroughly spaded, rodded, and worked with suitable tools sufficient ly to cause all air bubbles to escape, to work grout to face of form work, filling all voids, and showing a smooth, well-mixed concrete free from voids when forms are re moved.
That a fine mixture of 1 to 3 is deposited around and among the bars, and that it is thoroughly worked in. and around the bars in such a manner that the steel will be completely surrounded, embedded, and covered.
That all concrete is deposited in forms within 30 min utes after leaving mixer.
That all exposed surfaces of concrete are kept con tinually wet for a period of ten days after removal of forms.
In General. A record book will be furnished the in spector, in which a record will be kept of the progress of the work, and the following information should be re corded: Date; time of day of each entry; day or night work; number of men; foreman; condition of forms; con dition of steel; number and location of lights (if night work) and if properly lighted; number, time and location of test cubes taken; rate of mixing; size and number of batches; proportions of mixture ; name or number of work barge; arrival of material; kind and amount and on what barge.
Inspectors will be required to fill in several daily report blanks that will be furnished.
Inspectors will receive further written instructions from the Engineer-in-Charge from time to time, and will attach same to these instructions and will consider them a part of same.
Care should be taken not to allow the first concrete placed to appreciably stiffen or set before the remaining concrete is placed. The remedy for this is to add occa sionally, as often as is necessary, a little more concrete to that already placed over all exposed surfaces.
Great attention is necessary to make each section (pier, arch-ring, or spandrel wall) monolithic in height, length, and width. Only when circumstances render it practically unavoidable, may the work be stopped before the entire section is completed.
Order and close attention to details is essential. Care lessness in proportioning, in mixing or compacting the materials, or the omission or misplacement of the steel bars, may cause defective or even destructive results. Reinforced concrete construction requires close, continu ous, and intelligent supervision.