11.4 Connections 365
Plate Failure in Tension
Theareaofplateintensionalongthelineofrivetsisreducedduetothepresenceofrivetholes.Therefore,
iftheultimatetensilestressintheplateisσult,failurewilloccurwhen
Pb
t(b−d)
=σult
fromwhich
P=
σultt(b−d)
b
(11.3)
Shear Failure in a Plate
Shearingoftheplatesmayoccurontheplanesccresultingintherivetsbeingdraggedoutoftheplate.
Ifthemaximumshearstressatfailureofthematerialoftheplatesisτ 2 ,thenafailureofthistypewill
occurwhen
Pb= 2 atτ 2
whichgives
P=
2 atτ 2
b
(11.4)
Example 11.1
Ajointinafuselageskinisconstructedbyrivetingtheabuttingskinsbetweentwostrapsasshownin
Fig.11.12.Thefuselageskinsare2.5mmthickandthestrapsareeach1.2mmthick;therivetshavea
diameterof4mm.Ifthetensilestressinthefuselageskinmustnotexceed125N/mm^2 andtheshear
stressintherivetsislimitedto120N/mm^2 ,determinethemaximumallowablerivetspacingsuchthat
thejointisequallystronginshearandtension.
Fig.11.12
Joint of Example 11.1.