Double-deck rail vehicle and vehicle body thereof

A double-deck rail vehicle, comprising a vehicle body, wherein the vehicle body comprises:

• a chassis, a front end wall, a rear end wall, side walls and a roof, wherein the chassis comprises:
• a lower chassis provided with a chassis center sill extending in a length direction of the vehicle body;
• a first end chassis fixedly connected to one end of the chassis center sill through a first reinforcing center sill;
• a first closure plate fixedly connected between the first end chassis and the lower chassis, the first closure plate being configured to seal a gap between the first end chassis and the lower chassis;
• a second end chassis opposite to the first end chassis, the second end chassis being fixedly connected to the other end of the chassis center sill through a second reinforcing center sill;
• a second closure plate fixedly connected between the second end chassis and the lower chassis, the second closure plate being configured to seal a gap between the second end chassis and the lower chassis;
• a first lateral chassis comprising a first lateral chassis side beam formed in one piece, the first lateral chassis being fixedly connected to the first end chassis and the second end chassis through the first lateral chassis side beam;
• and
• a second lateral chassis opposite to the first lateral chassis, the second lateral chassis comprising a second lateral chassis side beam formed in one piece, and the second lateral chassis being fixedly connected to the first end chassis and the second end chassis through the second lateral chassis side beam,
• wherein each of the first end chassis and the second end chassis comprises a front end beam, a rear end beam, two end chassis side beams, a sleeper beam, and a traction beam, a force transmission beam being welded between the sleeper beam and the rear end beam and located at a position corresponding to the traction beam;
• the end chassis side beam comprises a U-shaped steel with an opening facing the traction beam and a side beam closure plate welded to the opening, each of the U-shaped steel and the side beam closure plate being formed in one piece;
• and
• an end, away from the traction beam, of the end chassis side beam has a variable cross-section structure which cause the cross-sectional area of the end chassis side beam to be gradually reduced in a direction from the front end beam to the rear end beam.