Control of subsidence with borehole extensometer and surveying measurements in Murcia, Spain

摘要

This paper describes a field investigation that belongs to a whole study of the Subsidence of Murcia city (southeast of Spain), produced by water level variations. This part of the study consist in monitoring and water level variations to calibrate a numerical model for predicting subsidence due to water level variations and determine alert levels. To obtain reliable information about ground level variations, 22 extensometers from 10 to 25 m length and 650 survey points were installed during 2001. The measurements are carried out each six months and should be continued at least until 2006. Nowadays six measurements have been carried out, allowing to check methodology, coherence of measurements and some first comparisons between real subsidence field data and numerical calculations.