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. 1911 Excerpt: ...+ 1-2QW = 2-8, whence 1-828 W = 2-3, or W _ T76 tons. The half load that might be expected on one side of the stanchion if the floor on 25 that side were fully loaded would be-= 12 tons, whereas, from the above calculation, it will be seen that only 1-76 tons could be safely so carried. This is a very serious matter, ...
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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. 1911 Excerpt: ...+ 1-2QW = 2-8, whence 1-828 W = 2-3, or W _ T76 tons. The half load that might be expected on one side of the stanchion if the floor on 25 that side were fully loaded would be-= 12 tons, whereas, from the above calculation, it will be seen that only 1-76 tons could be safely so carried. This is a very serious matter, and indicates a source of danger that few people are aware of. The weight of stanchion being, say, J ton, the total load to be carried by the base will be 25 + J = 25-25 tons. Assuming the cast iron base plate to rest on 1:4: 8 concrete capable of bearing 9 tons per square ft., the area of base plate required 25'25 will be Q = 2-8 sq. ft., or, say, 1 ft. 8 ins. square. It is generally advisable to make up for the section removed by the bolt holes in the base plate by adding a raised boss, as shown in Fig. 196, so that the section across the plate through the hole remains of the full original amount. A distributed load is transmitted from the cap and base plate most directly by plain hollow curves, as shown in Fig. 191, but for architectural effect the outline is sometimes varied, as shown in Figs. 192 to 195. The elevation of the stanchion may now be drawn out as Fig. 191, plan of base as Fig. 196, and plan on top as Fig. 197, which shows the socket for stanchion on upper floor and two side supports for floor girders. An example may now be taken of a hollow cylindrical cast-iron column 20 ft. high to carry 20 tons. The external diameter of the column will often not exceed jth of the length, and should not be less than g'gth in extreme cases. The thickness of metal may vary from th to-jth of the external diameter, but as a general rule columns of 6 ins. diameter and over should be not less than f in. thick, and under 6 ins. diameter not le...
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