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XIV. Strength of the Thin-plate Beam^ held at its ends and 

 subject to a uniformly distributed Load (Special Case), 

 By B. C. Laws; B.Sc, A.R.C.Sc, A.M.I.C.E.* 



IN a recent communication f the author gave the solution 

 of a special case of the thin-plate beam, in which the 

 uniformly distributed load was taken as acting downwards,. 

 i. e. so as to press the beam against the broad supports. 



As therein explained the case is met with in those struc- 

 tures as e. g. ships, and floating docks, built to withstand 

 hydrostatic pressure, where the shell plating is riveted to 

 and supported at frames or girders forming the foundation 

 of the structure ; and if we take a section of the plating in 

 the direction perpendicular to the frames we obtain the 

 profile of the beam forming the subject of discussion. 



In the present case the problem is considered wherein the- 

 load acts in the reverse direction ; the beam is not now 

 supported directly by the frames but by the rivets which 

 secure it to the latter. 



The appearance of the beam between consecutive frames 

 is of the nature indicated in fig. 1, in which F, F : denote 

 the frames, and r. r± the lines of rivets. 



Fig. 1. 



Plate beam with a uniformly distributed load iv per square inch. 



Such cases are commonly met with in practice, as e. g. in 

 the plating of the inner bottom and bulkheads of floating 

 structures, and give rise to stresses in the material different 

 from those obtained in the previous case. 



As before, consider a strip of plating of unit width and 

 thickness t, constituting a beam of length n\ = 2 a, and 



* Communicated bv the Author, 

 t Phil. Mag. vol. xxxi. April 1916. 



