# Public Water-Supplies; Requirements, Resources, and the Construction of Works

List price: US\$33.96

Currently unavailable

AbeBooks may have this title (opens in new window).

## Description

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 edition. Excerpt: ...of ABDC in the above equations. Thus the new value of m is n of eq. (9), etc. Third Stage.--For the next series of courses the face CE must be x battered so that n shall always be equal to--. The value of x is given by the equation Fourth Stage.--When by the use of (10) and (i i) the value of the pressure on the front face would exceed the formula is This value of x is to be used as soon as it becomes larger than the x value given by (10). The batter is still given by (n); also, n =--. Fifth Stage.--When the pressure on the back face becomes equal to q, then the formula is x =VD + E+E, (13) A + id9 + 2 in which D =--.--:, and =--, and the batter i. i -k -k W W A(4x-6m) + lhx-I) + x(h y= 6A + h2l + x)" '" ' Equation (13) is to be used when it gives a value of x greater than that QX found by eq. (12). For this case, n--x--i, Tt-. 'H; " wA + A') The foregoing equations are all that are needed in designing the profile of any high dam. In fact equations (12), (13), and (14) will not be used until a height of 100 feet or more is reached, depending upon the assumed values of p and q. Graphical methods of determining lines of pressures, and of checking the results found by algebraic processes, will readily suggest themselves to the student. 428. Effect of Approximations in the Foregoing Treatment.--The effect of neglecting the vertical component of the water-pressure on the inclined upper face is very small until the height becomes very great. Then this additional component acts to throw the resultant nearer the upper face and therefore to increase the pressures near this face and to decrease those near the lower face. In the last respect it tends to compensate for the error due to considering vertical forces...