Counterweight supporting structure for construction machine

A counterweight supporting structure for a construction machine having a counterweight and a vehicle body frame, the counterweight supporting structure comprising:

• a support plate fixed upright along a vertical direction to a rear portion of the vehicle body frame, a thickness of the support plate extending from a first face of the support plate to a second face of the support plate along a longitudinal direction, the longitudinal direction being perpendicular to the vertical direction;
• a base member attached to the support plate,
• a thickness of the base member extending from a first face of the base member to a second face of the base member along the longitudinal direction, the first face of the base member and the first face of the support plate each facing the counterweight;
• and
• a cylindrical bolt fastening boss defining a fastener hole extending through a length of the cylindrical bolt fastening boss along the longitudinal direction, an axis of the fastener hole being offset from a central axis that is centered on a cylindrical outer surface of the cylindrical bolt fastening boss,
• the length of the cylindrical bolt fastening boss at least partially overlapping with the thickness of the base member along the longitudinal direction,
• the thickness of the base member at least partially overlapping with the thickness of the support plate along the longitudinal direction, such that a periphery of the base member directly faces the thickness of the support plate, the first face of the base member extending beyond the first face of the support plate along the longitudinal direction and disposed in abutment with the counterweight,
• at least a portion of the periphery of the base member being welded to at least one of the first face of the support plate and the second face of the support plate.