三角高程法超长距离跨海高程传递实验研究

针对三角高程法跨海高程传递测量误差的来源问题,该文提出了基于三角高程法的超长距离跨海高程传递方法,设计了具体的测量方案,包括跨海场地选定与布设,观测标灯设计与制作,跨海观测时段数、测回数及组数设计,观测程序与观测方法、观测成果的限差验算与成果取舍等,并提出了跨海高程传递精度评定的两种方法。在平潭海峡公铁两用大桥工程现场选定两条跨海线进行了实验研究,实验结果表明,13.9km和18.0km跨距的跨海高差平差值与已知高差的较差均小于二等水准测量限差,每千米跨海高程测量中数的中误差分别为±0.68mm和±0.63mm。

Study of extra-long distance sea-crossing elevation transference based on trigonometric levelling

In view of the trigonometric levelling error sources of sea-crossing elevation transference,a method of extra-long distance sea-crossing elevation transference based on trigonometric leveling was put forward.Then the specific surveying scheme was designed,which included sea-crossing site selection and layout,design and manufacture of observation beacon,design of numbers of observation time periods,measurement times and groups,procedures and methods of observation,method of tolerance checking and acceptance or rejection rule of measurement results,and two precision assessment methods of seacrossing levelling were proposed.After that,the experimental research was carried out on the construction site of Pingtan Straits Rail cum-Road Bridge,in which two sea-crossing elevation transference lines were selected.The experimental results showed that the discrepancies between the sea-crossing measuring height differences and its known values of 13.9 km long and 18.0 km long line were all less than the tolerant error of the 2nd class levelling,and the errors of mean square of see-crossing height differences of the two lines were±0.68 mm and ±0.63 mm respectively.