Vehicle framework structure

1. A vehicle framework structure, comprising:

a left and right pair of side members that each extend in a vehicle front-rear direction;

a support member that is disposed in close proximity to the pair of side members in the vehicle front-rear direction, and that extends in a vehicle width direction;

projections that are each provided at the support member so as to project toward one or other of the side members;

joint members, an end at a support member side of each of the side members being inserted into a respective one of the joint members and the joint members being joined to the support member; and

first bolts that fasten joint members that are abutted against the projections in the vehicle width direction, and fasten the side members inserted into the joint members, to the projections, wherein:

the support member includes a body section that acts as a base for the projections in a direction opposite to a projection direction of the projections; and

the joint members each include:

an insertion portion into which the respective side member is inserted, and

an extension portion that extends from the insertion portion toward the body section side and that is configured to abut a face on a vehicle width direction side of the body section.

2. The vehicle framework structure of claim 1 , further comprising second bolts that fasten the extension portions to the body section.

3. The vehicle framework structure of claim 1 , wherein:

the joint members each include:

a pair of plate-shaped support plates configured to sandwich the side members, and

a plate-shaped coupling plate that couples ends of the pair of support plates, on the body section side, together; and

each extension portion is a plate portion that extends from the respective coupling plate toward the body section side.

4. The vehicle framework structure of claim 1 , wherein the joint members are each formed from an extruded aluminum member.

5. The vehicle framework structure of claim 1 , wherein the support member is made from die-cast aluminum.

6. The vehicle framework structure of claim 1 , further comprising welded portions that fix the side members to the joint members.

7. The vehicle framework structure of claim 1 , wherein:

the side members each have a closed cross-section structure; and

the first bolts are inserted through cylindrical bodies that are each made from metal and abut opposing inner wall faces of the respective side member.

8. The vehicle framework structure of claim 7 wherein the side members each include a rib that divides the side members into a top and a bottom.