Semi-trailer for transporting containers

The semi-trailer has a container chassis coupled with a towing vehicle. Locking devices (3) are arranged at a front section of the container chassis in a driving direction, with which a container to be accommodated is constantly lockable. A carriage (2) supported on two roll rails is guided at a rear section of the chassis, where the rails are supported at a main beam of the chassis. The rails and the carriage are arranged such that the rails are in effective connection with axle tubes (1) after lowering air suspension, where the container is detached from the chassis.