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1. Construction Work Classified. — For the sake of brevity we shall make frequent use of the term "Owner" as referring to the person, firm, private corporation or public corporation for whom construction work is done. While important work not infrequently necessitates, in these days, the coöperation of engineers in many capacities, we shall use the word “Engineer” in speaking of the Engineer employed by the Owner.

(a) The Engineer may, as agent for the Owner, direct all the operations, even to purchasing the materials and paying the workmen. The Panama Canal and the Los Angeles Aqueduct are being constructed under such an arrangement; the Corps of Engineers of the United States Army, various railroad corporations and some municipalities carry on a portion of their construction work under this or a slightly different plan. The term "force accountis generally applied to this arrangement, which is a very flexible one, but one to which slight reference will hereafter be made in this book.

(6) A modification of the above plan consists in the employment by the “Owner” of a third person, called a “Contractor,” who agrees to furnish whatever material and labor is from time to time needed and to direct the work (under the Engineer's supervision), in return for which he agrees to accept as payment an amount slightly greater than the cost to him. This is commonly called having a piece of construction done by day's work," although the term "force account” has been applied here as well. According to the terms of the agreement, the price paid the “Contractor” may be related to the cost to him in one of two ways, namely:

(i) Cost-plus-a-percentage. With this arrangement the price paid by the Owner is computed by summing up the cost, to the Contractor, of materials and labor (with sometimes a further allowance for incidental expenses such as depreciation, office rent, etc.), and adding to this sum an agreed percentage of profit.

(ii) Cost-plus-a-fixed-sum. This varies from (i) simply in that the amount added is a prearranged sum, not a prearranged fraction of the cost.

It may be said of the day's work plan (including both (i) and (ii)), that if no necessity exists for fixing in advance a maximum allowance of either time or money, and if unlimited confidence can be placed in the ability, energy and reliability of the Contractor, the method is nearly ideal. It is especially useful in emergency work, or for work the quantity or nature of which cannot well be foreseen, or for work of a hazardous or experimental character. The advantage of (ii) over (i) is that as profit no longer varies with cost to the Contractor, there is no temptation on his part to increase the cost. Comparatively little American construction work has been done under this plan, although a considerable number of buildings have, within recent years, been erected on the cost-plus-a-fixedsum basis.

The student is referred to Engineering News, 1912, vol. 68, p. 392, for the outline of a proposed sliding scale payment plan in which an incentive to economize is furnished the Contractor. This and like schemes, while ingenious, have not, to the author's knowledge, been given extensive trial in practice.

(c) Much the larger proportion of construction can be classed

“contract work." This is a convenient term for that which is carried on under an agreement by which the Owner is to pay the Contractor a definite sum for his work (or for each separate


part), regardless of the Contractor's profits. In contract work, although the Owner's interests are still looked after by the Engineer, much of the responsibility for the execution of the work is shifted to the Contractor's shoulders.

2. Contract Work. (a) Objections sometimes urged against “contract work”


(i) That profits are exorbitant. This is doubtless true at times, and where no bona fide competition exists. But, on the other hand, the student should recognize the fact that a reasonable percentage of a contract price is legitimate profit. Further than this, a Contractor is perfectly justified, as his work progresses, in endeavoring to increase his net profits by wise planning, careful supervision and economy -- not by

slighting his work or by endeavoring to substitute inferior workmanship or materials. The best work is not necessarily that which has proved most costly to the Contractor.

(ii) That undue haste may result in poor construction. Here again it is true that most kinds of work can be either well and rapidly done or poorly and rapidly done.

(iii) That altering the design is difficult and expensive. This is a valid objection only when the design cannot be thoroughly worked out in advance. (6) It

may be added, moreover: (i) That contract work is generally cheaper, since it lends itself more readily to competition.

(ii) That a definite price has oftentimes many distinct advantages for all concerned.

(iii) That in case the Owner is a public corporation, any other plan than that of contract work is commonly forbidden by law.

3. Documents. - In connection with a single piece of construction work done under contract it is frequently necessary to prepare six documents, viz:

(a) Contract,
(6) Bond (or bonds),

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