Concrete-Steel; A Treatise on the Theory and Practice of Reinforced Concrete Construction
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. 1905 edition. Excerpt: ...the lower part of the beam is drawn in broken lines. Let b = breadth of the beam = 5 d = depth from top of beam to axis of reinforcement /= clear span between supports Sx = distance between assumed diagonals = 10 in. w = load per inch of length =100 lb. 10 1n. 80 in. The load applied upon the top of the beam is practically equivalent, so far as concerns stress on the assumed diagonals, to downward vertical forces equal to wx, acting at eachof the points, av a2, a3, a4, and downward forces equal to wx, acting at the points a, a. The total tensile stresses along the diagonals may be ascertained by adding together the stresses due to the different weights, or by the simple rule, P, =----+ 1 wSx sec 6 (45) Where Pe = total tensile stress in any diagonal, N = number of bays formed by assumed diagonals, n-numerical order of any bay from the abutment, 6 = inclination of assumed diagonals. In this case the inclination of the diagonals to the horizontal is 45 deg., and the value of sec 1.41421, say 1.414. The value of wSx= 100 x 10= 1,000 lb. Calculating the tensile stresses in the diagonals for one half of the beam, we have. " (8-2 X l)+ I.. a b4, Vt =-x (1, ooo x 1.414) = 4,949 lb.;,000 x 1.414) = 707 lb. Dividing each of these results by the area of the diagonal plane = (10 x 5 x sec 6) = 70.7 square in., we have the intensity of tensile stress per square in., (jt) for each diagonal. Thus a bv pt = l lb. per square inch. A, A=5olb. " " asfiv Pt = 3o lb. " " aibv P'= 10 lo-, These figures show that in the case of abi the stress is beyond the limit of 50 lb. per square inch, generally taken as the allowable unit stress for concrete. Still, as the ultimate resistance of the concrete would probably be between 250...
- Paperback | 60 pages
- 189 x 246 x 3mm | 127g
- 26 Jun 2012
- Miami Fl, United States
- Illustrations, black and white