Strength of Riveted Joints, Strength of Materials | Strength of Material Notes - Agricultural Engg - Agricultural Engineering PDF Download

 Strength of Riveted Joints

Strength of a riveted joint in different failure mechanism is given bellow.

1.1 Tearing of plate

Fig. 26.1.

 The maximum allowable force P_t can be determined as,

\[{P_t}={\sigma _t}\left( {b - nd} \right)t\]

where,

\[{\sigma _t}={\rm{ allowable tensile stress of the plate material}}\]

\[b={\rm{ width of the plate}}\]

\[n={\rm{ number of rivets in the row where tearing takes place}}\]

\[d={\rm{ Diameter of the hole}}\]

1.2 Shearing of rivet

Fig. 26.2.

The maximum allowable force P_s can be determined as,

\[{P_s}=n{\sigma _s}\left({{\pi\over 4}{d^2}} \right)\]  for lap joints / single cover butt joints (Figure 26.2a)

\[{P_s}=2n{\sigma _s}\left({{\pi\over 4}{d^2}}\right)\]  for double cover butt joints (Figure 26.2b)

where,

\[{\sigma _s}={\rm{ allowable shear stress of the rivet material}}\]

\[n={\rm{ number of rivets in the row where tearing takes place}}\]

\[d={\rm{ Diameter of the hole}}\]

1.3 Crushing/ Bearing of rivet

The maximum allowable force P_b can be determined as,

\[{P_b}=n{\sigma _b}dt\]

where,

\[{\sigma _b}={\rm{ allowable bearing stress between rivet and the plate material}}\]

\[n={\rm{ number of rivets in the row where tearing takes place}}\]

\[d={\rm{ Diameter of the hole}}\]

Design strength of a riveted joint = min (P_t,P_s,P_b)

A multiple riveted joint may fail either in a single or a combination of above three mechanisms. In such cases all possible combination has to be considered in order to determine the design strength of the joint.