沉管隧道沉放对接监控中的超声阵列测量及其关键算法

水下高精度沉放对接是沉管隧道施工的一个关键环节，对测量方法的环境适应性和精度等指标要求很高. 目前实际工程中多采用高精度全站仪测量和刚性测量塔传递坐标的方法；此外，国外提出水下声呐测量方法，环境适应性强，且精度不随隧道长度增加而下降. 本文通过对水下声呐法进行创新改进，采用三点后方交会方法，提出超声阵列测量方法，并用于佛山汾江路南延线沉管隧道工程中管段沉放对接的测量监控试验，并将测量结果与高精度全站仪测量结果进行了对比分析. 现场监测试验结果表明，该方法能够满足工程需要，在管段间距2 m时，三轴坐标测量精度不大于± 45 mm.

Ultrasonic Array Measurement and Key Algorithm in Monitoring of Immersing and Docking of Immersed Tube Tunnel

The high precision immersion and docking is the key part in immersed tube tunnel construction，which requires better?environmental?adaptation and high accuracy to the measurement system. Now，the high-precision total station and rigid measurement tower are commonly used in actual engineering. Moreover，the sonar method is also proposed in foreign country，which has good adaption to the surrounding and its precision does not decline with the tunnel length increasing. Through innovation?and?improvement based on the underwater sonar methods，the ultrasonic array measurement system was proposed by the three points resection method and was used to measure and monitor the immersed tube tunnel immersing and docking process of Foshan Fenjiang road extending to the south. Compared with the high-precision total station，the method can meet?the?needs?of engineering，and the 3-axis measurement precision can be controlled between +45 mm and -45 mm when the distance between two tubes is 2 m.