THE BEHAVIOR OF RIVETED JOINTS UNDER STRESSES. 137 



should be, represented by the elastic limit of the rivet metal. Whether this force 

 drawing the plates together is acting to its full extent will depend upon the manner 

 in which the riveting is done. A limited range in temperature in cooling is sufficient 

 to apply a contractile force equal to the elastic limit of the rivet metal. But since 

 the hot rivet metal has a very low elastic limit it is necessary to hold the plates to- 

 gether firmly until the rivet has cooled to nearly its final temperature. This require- 

 ment is an obstacle to rapid driving, as will be readily seen, but full efficiency in 

 frictional resistance between the plates requires its observance. 



To attain a high degree of efficiency a state of rigidity in the joint, comparable 

 to that of the plate, is essential. If not attained, the distribution of the stresses will 

 not be as they are expected and computed. The few examples in which the strains 

 in structures have been measured do not furnish ground for the belief that very 

 good distribution is attained in current practice in all classes of structures. The 

 conditions attending marine work would seem to make greater demands on the rivet- 

 ing than in most engineering structures. 



This paper has not taken the form which it was hoped that it might. It was 

 desired to present orderly arranged data covering the details which have been men- 

 tioned and others which have not been touched upon. This was found to be imprac- 

 ticable in the time which could be given to it. It is believed, however, that this re- 

 view of the subject will show its general status and indicate those features which 

 should be considered when designing riveted connections, and, furthermore, that 

 riveted joints are not to be taken as the equivalent of the solid plate, except, it may 

 be, for working loads of small magnitude. 



The Chairman : — Gentlemen, this paper is before you for discussion. Does any mem- 

 ber wish to discuss it? If not, in your behalf, I tender the thanks of the Society for his 

 interesting presentation of this matter. 



We will now proceed to the next paper, No. 11, "Our First Frigates. Some Unpub- 

 lished Facts about their Construction," by Hon. Franklin D. Roosevelt. In the absence of 

 Mr. Roosevelt the paper will be presented by Mr. Linnard. 



Mr. Linnard read the paper. 



