An account of certain tests of the transverse strength and stiffness of large spruce beams

✍ Scribed by Gaetano Lanza

• Publisher: Elsevier Science
• Year: 1883
• Tongue: English
• Weight: 552 KB
• Volume: 115
• Category: Article
• ISSN: 0016-0032
• DOI: 10.1016/0016-0032(83)90344-7

✦ Synopsis

GENTLEMEN :--I beg leave to call your attention to the results of certain tests of the transverse strength and stiffness of full size spruce beams, carried on by members of my classes in my laboratory at the Massachusetts Institute of Technology. The machine with which they were made is a 50,000 pounds machine, and is capable of testing beams twenty-five feet long and under, as well as many of the framing joints used in practice.

It consists, as shown in the cut, of a compound lever, hung in a cast iron frame, to which is connected, by means of a steel rod and turn buckle, one end of a lever, of equal arms, placed below, this lever having a 12-inch leverage, and being connected at its other end by means of a chain, with the yoke shown in the cut. Two hard pine beams, each 20 inches deep, 10 inches wide and 26 feet long, are laid across the timbers of the machine in such a way that the chain WHOLE No. VoL CXV.--(Tm~D SERI~S, Vol. lxxxv.) 6 * [We are indebted to the Boston Journal qf Commerce for the use of this cut.]