This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1890 edition. Excerpt: ... CHAPTER HI. TRUSSES FOR FLAT ROOFS. 25. Trapezoidal Truss; Equal Loads.--A consideration of the trapezoidal, or queen-post, truss, represented by Fig. 14, will bring out two or three points which will be of use in the analysis of other trusses. In this case, let us suppose the load to be on the lower ...
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This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1890 edition. Excerpt: ... CHAPTER HI. TRUSSES FOR FLAT ROOFS. 25. Trapezoidal Truss; Equal Loads.--A consideration of the trapezoidal, or queen-post, truss, represented by Fig. 14, will bring out two or three points which will be of use in the analysis of other trusses. In this case, let us suppose the load to be on the lower part, or bottom chord, of the truss. In order to separate the supporting forces from the small weights on the ends of the truss, and to permit them to come consecutively with the other weights in the load line, let us draw the supporting forces above the tie, instead of below as before. The rectangle formed by the two vertical and two horizontal pieces might become distorted; we will therefore introduce the brace H I, represented by the full line. The rectangle is thus divided into two triangles and movement prevented. The dotted line shows a piece which might have been introduced in place of the other. If the truss is symmetrically loaded, or C D = D E, we shall get the first stress diagram. The stress in each vertical is here seen to be the load at its foot. The stress in the piece H I proves to be zero. If the load had been on the upper joints, no stress would have been found in the vertical;, also. (See 17.) It is evident that a trapezoidal truss, when symmetrically loaded, requires no interior bracing. This fact might readily be seen if we considered the form assumed by a cord, suspended from two points on a level, and carrying two equal weights symmetrically placed. 26. Trapezoidal Truss; Unequal Loads.--The second stress diagram will be drawn when the weight C D is less than D E. Let us suppose that b c and ef are of the same magnitude as in the first diagram, and let the span of the trass, or distance between supports, which..."
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Add this copy of Trusses and Arches Analyzed and Discussed By Graphical to cart. $34.96, good condition, Sold by Bonita rated 4.0 out of 5 stars, ships from Santa Clarita, CA, UNITED STATES, published 2018 by Palala Press.
