Application of Microgravity to the Assessment of Existing Structures and Structural Foundations

摘要

The report evaluates microgravity and other geophysical techniques, applied to the detection of density anomalies in structures and in their foundations. Microgravity measurement and processing techniques, as well as in-situ density evaluation (including the Cheops pyramid) are described. The report summarizes microgravity techniques. After a description of field techniques, the main interpretation techniques, both conventional and innovative, are described. The report describes the application of microgravity to the direct in-situ measurements of embankment densities and to the assessment of foundations of existing structures, and includes the description of the Cheops survey. The report describes the use of microgravity for grouting control and other repeat surveys. The report compares microgravity with other geophysical methods in the fields of cavity detection and grout control. It describes the use of resistivity, electromagnetics, seismic methods and down-hole logging. The report compares current French practice in the field of cavity detection, with methods used in the rest of the world. (jhd)