Analysis On Several Problems Of The High Speed Railway Control Measurement

This paper analysis the high speed railway control network at all levels about the technical requirements and its accuracy standard for measurement and control system,analysis the main error sources of measuring all levels of control network in the process of the rail line construction, including GPS and total station traverse survey and leveling from three aspects, weakening the corresponding error measures are put forward, lays a foundation to reaching the precision requirement of related specification and minimize measurement error.In the concrete slab ballastless track base construction process, plane layout and vertical layout is separately, plane layout method for edges free resection method, elevation layout method for precise leveling method, discusses methods instead of precise leveling by precise triangulated height surveying, the feasibility of, make the layout of the elevation and the plane layout simultaneous, can improve efficiency. the CP Ⅲ high-precision track-laying control network based on the precision of the overlapping free station can completely satisfy the requirements of high-speed measurement accuracy. In the slab ballastless track plate lofting and orbital plate installation, calculate the farthest lofting distance according to the instrument error parameters on each station under the lofting error do not overrun to provide the reference. Smooth high speed railway puts forward higher request about smooth in trajectory, make the turning radius of the design orbit is more and more big, the line construction in mountain areas are often across the long tunnel,in view of the long large tunnel transfixion measurement problem, put forward use the method of free stationing marginal resection of high-speed CPⅢ track-laying control network to measuring the hole, and comparing with the traditional wiring method, verified the feasibility of this method use in the large long tunnel linking.According to the rail line for strip and miles long fundamental characteristics,research three kinds of methods to minimize projection deformation when line plane measuring using gauss projection to got plane coordinates, in order to make projection deformation within the scope of the related accuracy requirement. Recognizing the deficiencies of Gauss projection in the High-speed Rail line projection, this paper introduces a kind of oblique Mercator projection model and study its application in the High-speed Rail projection. Through the analysis of examples validate this projection method used in the High-speed Rail projection is feasible and have obvious advantages.