短视距精密三角高程测量在沉降监测中的应用

Short distance precision trigonometry leveling and application to subsidence monitoring

提出了一种不测量仪器高和棱镜高的短视距精密三角高程监测沉降的测量方法,经理论分析和试验验证,其精度完全可以达到二等水准.将此方法运用于扬州市人防工程的沉降监测,共观测了11期,各期观测的环闭合差均优于二等水准的限差,平差后的最大高程中误差均小于1mm,且各监测点的升降与抽水井的降水或回灌完全吻合.

Trigonometry leveling without measurement of the height of the instrument and prism is explored. Theoretical analysis and experimental tests show that the precision of trigonometry leveling is achieved that of second leveling. Application of trigonometry leveling to subsidence monitoring of engineering, the consequence obtained is satisfactory. Up till now, 11 measurements have been completed, error of close of each measurement is better than admissible error of second leveling, and the maximum altitude mean error of each measurement is less than 1 mm. Descent or ascent of monitoring points are consistent with that of water pumped out or back into the wells.