692 
MR. FAIRBAIRN’S EXPERIMENTAL INQUIRY 
Strength as 25,030: 18,591, or as 1 : '742, the comparative strength of a single riveted 
plate of equal area through the line of the rivets. It will be observed that in this 
comparison the areas of the sections are nearly equal, and consequently there is a 
difference in strength between the solid part of the plate and that part where the 
perforations have been made of 32 per cent. The difference is considerable, but it 
probably arises from the narrowness of the specimen and the lateral strain induced 
by the position of the rivet, and the bending upwards of the end of the plates. From 
these facts I would infer that single riveting is weaker, and probably the loss of 
strength in this description of joint, including loss caused by the rivet-holes, is not 
less, under ordinary circumstances, than 40 per cent. 
Table VII. Strength of riveted Plates. 
No. 
of 
exp. 
Description of plates 
and mode of riveting. 
Weight 
laid on 
in lbs. 
Changes produced by 
weight. 
Breaking 
weight in lbs. 
Form of specimen and mode 
of fracture. 
Remarks. 
30. 
Plates 22 inches 
thick, with three ri- 
vets, eaeh f inch dia- 
meter, AB 3 inches, lap 
1^ inch, area through 
rivet-holes -4125 ... 
Fig. 5. 
14,839 
Bent into a 
straight line. 
16,603 
Q 
( 
Q 
3 
\ 
A 
ooo 
© 
0 
Q> 
Fig. 6 
Q O 
Q 
3 
A 
f 
A 
Q 
Q Q 
B 
) 
L 
Q 
0 
G 
3 
The plates were sound, but two of 
the rivets were cut directly across. 
Rivets too weak. 
B ' 
31. 
32. 
Plates the same as 
before, overlap joints 
diifering from the last 
in having three rivets 
i inch diameter, form- 
ing an isosceles tri- 
angle, AB 3 inehes ... 
Same as before 
18,667 
Joint apparently 
sound. 
20,683 
Single rivet 
slightly opened. 
22,027 
The other two 
rivets quite tight. 
18,667 
Separation at end 
of plate, single rivet 
slightly opened. 
22,027 
23,035 
Slightly drawn at 
the rivets 
22,699 
23,371 J 
With the first weight the plates 
became bent, so as to be in a direct 
line with the straining force. 
Tore across the two rivet-holes, 
in the direction AB. 
With 22,027 lbs. the single rivet 
seemed somewhat opened, but the 
other two seemed quite close. 
Plate tom across at the single 
rivet and one of the double ones. 
Rivets sound in this and the pre- 
ceding experiment. 
In the first experiment the rivets (two in number) were evidently too weak, which 
caused them to shear directly across as if cut by a pair of scissors. In the next ex- 
periment the rivets were increased in number and size, which gave an excess of 
strength to the retaining power of the rivets and caused the plate to tear. If we take 
the mean of the experiments as respects the area of the rivets to that of the plates. 
