350 CAMBBIA STEEL. 



EXPLANATION OF TABLES OF RIVETS AND PINS. 



RIVETS. 



In the design of riveted joints the total stress transmitted is 

 assumed to be taken up by the rivets, no allowance being made 

 for the friction between the plates riveted together, and the 

 manner of failure of the joint will be by shearing of the rivet or 

 crushing of the plate. This assumes that the rules given on 

 page 358 are followed and failure by tearing off the plate caused 

 by the rivets being too near the edge is thus prevented. 



In the table of "Shearing Value of Rivets and Bearing Value 

 of Riveted Plates," pages 352 and 353, these values are given 

 for all customary sizes and thicknesses corresponding to various 

 usual allowable unit stresses. 



For any given size of rivet or thickness of plate to be used, an 

 inspection of the table will show at once if the bearing value of 

 the plate or the shearing value of the rivet is to govern the design 

 and the amount of stress that can be transmitted by each rivet. 



PINS. 



In designing pin-connected joints the points which govern the 

 design are the bending moments produced in the pin by the bars 

 or plates connected, and the bearing value of the plates them- 

 selves. The bearing value in the case of eye-bars of proper 

 proportions is sufficiently ample and need not be computed. 

 Shear in pins need not ordinarily be considered, as the bending 

 and bearing stresses usually determine the size. 



In the table of "Maximum Bending Moments on Pins," pages 

 360 and 361, is given the allowable bending moments on pins of 

 various diameters for the usual allowable fibre stresses. 



In the table of "Bearing Values of Pin Plates for One-Inch 

 Thickness of Plate," on page 359, is given the allowable bearing 

 values of plates against pins of various usual diameters, cor- 

 responding to the customary unit stresses of this character. 



If the bearing value exceeds the allowable limit in any given 

 case pin-plates must be added, thus increasing the bearing value 

 until it is reduced to a safe limit as shown by the tables. 



