高速铁路跨海大桥首级GNSS控制网技术研究OA

Aimed at the difficulties of long sea-crossing distance,complex and disadvantageous satellite positioning environment,high accuracy requirements and no relevant surveying technical standard to follow,we carried out the technical study on necessary accuracy,coordinate system,network setting-up,field surveying and data processing of the primary GNSS control networks of high-speed railway sea-crossing bridges,rely-ing on the Hangzhou Bay sea-crossing bridge of Nantong-Suzhou-Jiaxing-Ningbo high-speed railway.Then,we proposed methods of determining the necessary accuracy of control network based on the allowable construction deviations of sea piers of bridge,using precise point positioning technology to obtain the precise coordinates of baseline starting point,and data processing for accurate connection between the control network of sea-crossing bridge and the high-speed railway frame control network(CP0).The feasibility and effectiveness of those methods were verified by the measured data.The research fruits of this paper will be used as reference for the primary GNSS control network surveying of other similar sea-crossing passage engineering,and the development of relevant technical standards.