Subsidence Monitoring Technology of Temporary Railway Bridge Above Deep Pit

Against the background of a static monitoring project of steel latticed column temporary railway above soft soil deep pit,this paper introduces a new practical leveling method which adopts trigonometric leveling instead of second grade leveling,and homemade embedded prisms as elevation starting point,to better assist the Leica TCA1201+Measurement robots' work.Practice shows that this method meets the accuracy requirement and ensures the safe operation of the temporary railway bridge as it enables surveyors avoid working under a dangerous environment.It has a certain guiding significance for future bridge monitoring.