A liquid vehicle tank (1) having a wall made of a plastic material, the tank (1) comprising a component (3, 5) affixed to the wall, the component (3, 5) having a portion (10) embedded in the wall, the embedded portion (10) having an external surface (21) a part of which is chemically incompatible with the plastic material of the wall, wherein the tank (1) also comprises a strengthening element welded to the wall over the embedded portion (10) of the component (3, 5).

According to one implementation, a composite material structure includes a first member and a second member. The first member has at least one first bonded surface. The second member has at least one second bonded surface to be bonded to the at least one first bonded surface. The second member is made of a composite material. At least one surface formed by fibers forming the composite material is used as the at least one second bonded surface by disposing end portions of the fibers, in the first member side, inside the composite material.

According to one implementation, a composite material structure includes a first member and a second member. The first member has at least one first bonded surface. The second member has at least one second bonded surface to be bonded to the at least one first bonded surface. The second member is made of a composite material. At least one surface formed by fibers forming the composite material is used as the at least one second bonded surface by disposing end portions of the fibers, in the first member side, inside the composite material.

A fuel tank having a wall with an opening, the wall having a fuel impermeable layer, the fuel tank comprising a component welded to the wall around the opening, the component having a fuel impermeable layer, wherein the fuel tank comprises a fuel impermeable insert, at least partially embedded in the wall around the opening and arranged in between the two fuel impermeable layers.

Provided is a resin profile joining method of joining a pair of resin profiles. The method includes: holding one resin profile and another resin profile of the pair of resin profiles with a first mold and a second mold, respectively; heating the end surfaces of the pair of resin profiles in no contact with the end surfaces of the pair of resin profiles to melt the pair of resin profiles; after the heating, moving each of the first mold and the second mold relative to the pair of resin profiles in a longitudinal direction of a corresponding resin profile of the pair of resin profiles; and crimping the end surfaces of the pair of resin profiles to each other while keeping the first mold and the second mold in contact with the surfaces of the pair of resin profiles.