The invention discloses a device for measuring the dumping volume of a shield construction on line based on profile scanning, and relates to the field of measurement of shield constructions. An n-shaped vertical bracket is arranged on the two sides of a
belt conveyor and is perpendicular to the conveying direction of the
belt conveyor; three two-dimensional
laser scanners are arranged on the bracket; mounting centers of the three two-dimensional
laser scanners are positioned on the same horizontal line; a friction wheel is connected with a
rotary encoder through a coupler, is arranged on the lower surface of the
belt conveyor and is tightly attached to the lower surface of the belt conveyor; a nylon supporting plate is arranged on the lower surface of a conveying belt on the measuring section of the belt conveyor; a
main processing unit is used for
processing a transverse outline acquired by scanning and calculating the current cross section area by a numerical integration method; the friction wheel is used for measuring the speed of the belt conveyor, and the speed is integrated to acquire the current soil
body volume; and an upper computer is used for displaying the current soil
body volume in real time. By the device, the soil output of the shield construction can be accurately measured on line in the process of conveying
muck by using the belt conveyor.