Underframe structure for a motor vehicle comprising a lateral reinforcement part

An underframe structure for a motor vehicle, the underframe structure comprising a floor and at least two side members respectively disposed at each longitudinal edge of the floor, each of the at least two side members being longitudinal;

• the floor being divided into at least one front unit;
• and one rear unit fixed to a transverse heel board;
• wherein the underframe structure further comprises at least one lateral reinforcement part which comprises at least one elongate body extending from the heel board towards a closest one of at least two side members, further wherein the at least one lateral reinforcement part is fixed on one side to the heel board, and on the other side to one of the at least one front units of the floor or to the closest one of at least two side members, and wherein the at least one lateral reinforcement part comprises a rigid zone fixed to the heel board and a compressively deformable zone;
• the compressively deformable zone comprising means that promote its deformation;
• the means promoting the compressive deformation of the deformable zone comprise at least one of the following elements:
• a different grade of material with respect to the rigid zone, a different sheet thickness with respect to the rigid zone, one or more notches, apertures, corrugations, ribs, or a rim or a combination thereof.