Lateral dump truck and self-discharging method

Disclosed are a lateral dump truck and a self-discharging method. An original domestic lateral dump truck, namely an automatic dumping car, is small in volume and only can reach the designed load when loading particulate cargo with the specific gravity larger than 2.2 tons/ . The lateral dump truck comprises a truck bed component (4), cylinders (5) with control systems are connected with two sides of the truck bed component which is connected with a floor beam component (2) with a floor beam via support rollers (20) on the two sides, the floor beam component is connected with bogies (3) via top center plates (23), and coupler buffer devices (1) are connected with two ends of the floor beam. The lateral dump truck is used for transporting particulate cargo in a railway.