一,外业图板涂塑料保护液 航道工程测量的特点,是经常性地在一个固定区域(即某一个港区或某一个浅滩河段)进行水深测量。在一个水文年度内,某一固定区域一般要进行几次乃至二十余次的水深测量。 在进行水深测量时,是将绘制了坐标格网、原点(图根点)、陆上地形(主要是堤岸线)的图板,携至外业现场(测深船上)。 First, the field map coated with plastic protective liquid waterway engineering measurement is characterized by regular in a fixed area (that is, a certain port area or a shoal) for water depth measurement. In a hydrological year, a certain fixed area generally need to do several or even more than twenty times the depth of the measurement. During the water depth measurement, the drawing plate with coordinate grid, origin (root point) and land topography (mainly embankment line) is taken to the field site (sounding ship).