VEHICLE LOWER PART STRUCTURE

To provide a vehicle lower part structure capable of suppressing floor vibration by improving the rigidity of a floor panel while suppressing generation of a weight increase.SOLUTION: A vehicle lower part structure 100 includes a floor panel 102 forming a floor surface of a vehicle and a first cross member 110 extending in the vehicle width direction on the upper side of the floor panel. The floor panel includes a bead which is a protruding bead 124 upward of the vehicle and crosses the first cross member and extends in the cross direction of the vehicle and is joined to the first cross member and swollen parts 128, 130, 132, 134 formed in regions 140, 142, 144, 146 partitioned by the first cross member and the bead and swelling downward of the vehicle. The bead includes adjacent parts 148, 150 which are adjacent to the swollen parts and extend in the vehicle cross direction, and a wide part 152 which continues to the adjacent part, has a wider width in the vehicle width than the adjacent part and overlaps on the first cross member.SELECTED DRAWING: Figure 2 【課題】重量増加を抑えつつ、フロアパネルの剛性を高めてフロア振動を低減できる車両下部構造を提供する。【解決手段】車両下部構造１００は、車両の床面を形成するフロアパネル１０２と、フロアパネルの上側で車幅方向に延びる第１クロスメンバ１１０とを備え、フロアパネルは、車両上方に凸のビード１２４であって、第１クロスメンバと交差して車両前後方向に延び第１クロスメンバに接合されるビードと、第１クロスメンバとビードで区画された領域１４０、１４２、１４４、１４６内に形成され車両下方に膨出した膨出部１２８、１３０、１３２、１３４とを有し、ビードは、膨出部に隣接して車両前後方向に延びる隣接部１４８、１５０と、隣接部に連続していて隣接部よりも車幅方向の幅が広く第１クロスメンバに重なっている幅広部１５２とを含むことを特徴とする。【選択図】図２