This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1903 Excerpt: ...in the new ducts. If ducts are installed which are not needed for a long period of time, the interest upon the capital invested in their installation, the inevitable depreciation, the cost of maintenance necessary to keep them in good condition, will form an annual charge against them. The sum of these items must be ...
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This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1903 Excerpt: ...in the new ducts. If ducts are installed which are not needed for a long period of time, the interest upon the capital invested in their installation, the inevitable depreciation, the cost of maintenance necessary to keep them in good condition, will form an annual charge against them. The sum of these items must be contrasted with the cost of opening the street and placing ducts at such future time as will call for increased conduit capacity. If in any instance the probable time elapsing before additional conduit capacity will be needed can reasonably be estimated, the cost of the superfluous ducts placed when the system is built, plus the annual charges against them, may be contrasted with the expense of in 0 2 4 6 8 10 12 14 16 18 30 22 24 Years Fig. 58. Number of Ducts. stallation in the future, and a decision as to which plan is the more economical reached. To facilitate such calculation attention is directed to Fig. 58. This table shows four curves, calculated for varying cost of street paving, from 50 cents to 13.00 per square yard. The horizontal scale gives the number of years, while the vertical scale is devoted to the number of idle ducts. The use of the table is illustrated by the following example: Suppose a conduit of 16 ducts to be in process of construction, and that it is probable that after a certain lapse of time 20 ducts will be needed. The question arises at once, Shall the four additional ducts be placed at the time of original construction, or shall they be left for future installation? Assume paving to be worth $2.00 per square yard, and that 20 ducts will be needed before the lapse of four years. Select on the left-hand scale the number 20, and follow a horizontal line to curve marked $2.00, and a vertical line downward to the horiz...
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Add this copy of Construction of Underground Conduits to cart. $42.66, new condition, Sold by Media Smart rated 4.0 out of 5 stars, ships from Hawthorne, CA, UNITED STATES, published 2019 by Wentworth Press.
Add this copy of Construction of Underground Conduits to cart. $45.96, good condition, Sold by Bonita rated 4.0 out of 5 stars, ships from Newport Coast, CA, UNITED STATES, published 2019 by Wentworth Press.
