Tunnel section sedimentation and convergence analytical instrument and measuring method

The invention discloses a tunnel section sedimentation and convergence analytical instrument and measuring method. The analytical instrument comprises a semi-circle accurate laser ranging system which is connected with a system host. The system host is fixed on a host carrying plate, a front verticality measuring laser system and a rear verticality measuring laser system are arranged on the front and rear sides of the host carrying plate respectively. A left level bubble and a right level bubble are arranged on the left and right sides of the host carrying plate respectively. A left horizontality fine adjuster and a right horizontality fine adjuster are arranged on the left and right sides of the front verticality measuring laser system respectively. The host carrying plate is fixed on a tripod carrier system. The analytical instrument and the measuring method have the advantages that the front and rear verticality measuring laser systems are arranged on the instrument, so that the consistency and the accuracy of the instrument section before and after measurement are guaranteed; by the aid of the semi-circle accurate laser ranging system, sedimentation or convergence values of 19 measurement points o the tunnel can be measured accurately, and sedimentation or convergence of the tunnel section is monitored effectively.