Underwater step-by-step adjusting butt-joint structure for super-large-diameter shield tunnel and detection method

The invention relates to an oversized-diameter shield tunnel underwater step-by-step adjusting butt joint structure and a detection method. The oversized-diameter shield tunnel underwater step-by-step adjusting butt joint structure comprises a first arrival shield, a second arrival shield, a tunnel axis monitoring control system, a three-dimensional laser scanning system, a cutterhead, a GPS monitoring system and a shield tunneling machine automatic monitoring system, and the tunnel axis monitoring control system is composed of the three-dimensional laser scanning system, the cutterhead, the GPS monitoring system and the shield tunneling machine automatic monitoring system. During each stage of adjustment, the monitoring results of the GPS monitoring system and the shield tunneling machine automatic monitoring system are compared, the actual shield axis position is determined, the three-dimensional laser scanning system is used for determining the actual shield attitude and measuring the actual cutterhead inc