Monitoring of earthen long linear embankments by geophysical tools integrated with geotechnical probes

The use of electrical conductivity measurements from a non-invasive hand held electromagnetic probe is showcased to monitor the water content of earthen embankments at routine inspections. A methodology to convert the electrical conductivity measurements from the electromagnetic device into water content values is illustrated. The methodology is based on measuring the soil electrical conductivity variation with respect to a baseline reference condition and calibrating a water content – electrical conductivity relationship by comparing electrical conductivity readings from the electromagnetic probes with water content readings taken from geotechnical probes installed in a few sections of the embankment. The values of water content converted from the conductivity measurements according to the proposed procedure were found to be in very good agreement with independent measures of water content taken at times well beyond the calibration period.

Experimental assessment of alluviation downstream of Hun-lock, Belgium

To maintain inland navigation, a deposition crest in the Hunlock area, in the Upper Meuse River, Belgium, has to be dredged almost every two years. A long-term solution is searched for, based on the understanding of water velocity field and solid transport processes, to avoid the silting and the expensive dredging. The physical process is analysed thanks to a 1:50 small-scale model of the 500 m-long Meuse reach with Hun movable dam as upstream boundary. The velocity fields, recorded with an electromagnetic probe displaced automatically, are compared for several configurations. Three discharges and distinct dam openings are tested in the existing configuration. Modifications of the downstream guard wall, by perforating ports, are also considered. Building groynes in the right side of the river is analysed. Finally, flushing water through the lock is tested. As conclusions, alluviations are due to the localisation of the lock in an enlarged area of the Upper Meuse and in a meander intrados, inducing decreasing flow velocities. None of the tested solutions is completely convincing according to 4 criterions: (1) ability to decrease the deposition crest, (2) navigation requirements, (3) safety in case of high-stage discharges, and (4) acceptable cost.

Manufacturing and Characterization of Nanostructures Using Scanning Tunneling Microscopy with Diamond Tip

Nanoscale experiments with diamond tip that include processing, visualization and tunneling spectroscopy of the surface are presented. Single crystal diamond synthesized by the temperature gradient method under high pressure–high temperature (HPHT) conditions is proposed as a multifunctional tip for scanning tunneling microscopy (STM). Sequence of the procedures covering growing crystals with predetermined physical properties, selection of the synthesized crystals with the desired habit and their precise shaping have been developed. The original STM’s peculiarity is the electromagnetic probe-to-surface load measuring system. The results of fabrication and characterization of nanostructures for nanoelectronics, data storages and biology are demonstrated and discussed.