Introduction:
The edge distance in riveted connections is the distance between the center of the rivet and the edge of the plate element. It is an important factor to consider in structural design as it affects the strength and stability of the connection.

Explanation:
The correct answer to this question is option 'A', which states that the edge distance is measured perpendicular to the direction of force. Let's understand why this is the case.

Importance of Edge Distance:
The edge distance is crucial in determining the load-carrying capacity and performance of the riveted joint. Insufficient edge distance can lead to various issues, including stress concentration, reduced strength, and potential failure of the connection.

Perpendicular to the Direction of Force:
The edge distance is measured perpendicular to the direction of force because it is in this direction that the load is primarily transferred through the rivet. When a force is applied to the joint, it is transmitted from one plate to another through the rivet. The load is distributed over the area around the rivet hole, and the edge distance plays a significant role in this distribution.

Effect on Stress Concentration:
When the edge distance is inadequate, the stress concentration at the edge of the plate increases. This can lead to premature failure due to high localized stresses. Therefore, it is essential to maintain a sufficient edge distance to minimize stress concentration and ensure the structural integrity of the joint.

Effect on Shear and Bearing Strength:
The edge distance also affects the shear and bearing strength of the riveted joint. Adequate edge distance allows the load to be distributed over a larger area, reducing the stress on the rivet and the surrounding material. This improves the overall strength and performance of the connection.

Design Considerations:
In structural design, specific guidelines and standards provide recommended minimum edge distances for different types of rivets and materials. These guidelines ensure that the edge distance is sufficient to meet the required strength and performance criteria.

Conclusion:
In conclusion, the edge distance in riveted connections is measured perpendicular to the direction of force. Adequate edge distance is essential to minimize stress concentration, improve the load-carrying capacity, and ensure the stability and strength of the connection. Design guidelines should be followed to determine the appropriate edge distance for different applications.