One of our goals is to find out what the current state is, a T0 baseline, of our levee condition. This is required to evaluate impact of the tests in relation to the parameters that characterize the several levees, as there are differences in structure, slope, vegetation, etc. The data that are needed to form a baseline dataset are gathered by survey.
About the survey
This survey is the performance of all measurements that are not related to a specific test condition or experiment execution. It contributes to the collection of the background information and site description data.
Subtasks needing data
Data needs emerge from several subtasks of the project, including:
- Scenario Development that will build a test programme on a number of research questions for which suitable data is required
- Monitoring may define requirements to survey data so that data collected during the tests is comparable to the data collected outside the testing period
- Data Management which may set requirements related to data format and metadata
- Model validation, which will yield data requirements from the model point of view; i.e. damage, geotechnical and hydraulic models will require certain types of data.
Required data sets
From an experimental and data analysis point of view, the following data sets are required:
- Detailed geometry of the levees.
- Geotechnical and sedimentological properties of the top soil and deeper structure, properties of the cover layer including vegetation; morphological defects, such as burrows or wet spots.
- Hydraulic properties of the levee structure.
We have selected the following survey techniques, see the list of survey types and items:
Topography & surface mapping
- Real-Time Kinematics (RTK) profiles over levee and on marsh
- Laser Imaging Detection and Ranging (LIDAR) scans of selected levee parts
- Aerial RGB orthophoto mapping
- Aerial Photogrammetric Digital Terrain Model (DTM)
- Aerial Infrared photography of selected parts
- Survey of revetment types and levee surface properties, including animal burrows
Sedimentological and geotechnical soil properties
- Hand drilling on levee and marsh
- Machine (deep) drilling on levee
- Soil testing of selected samples (different techniques)
- Cone Penetration Testing (CPT) on levee and marsh
- Jet erosion test on levee
- Grass pulling test on levee
- Slingram method
- Electrical Resistivity Tomography
- Ground Penetrating Radar
Hydraulic and hydrologic properties
- Water level in Scheldt (part of continuous system monitoring)
- Hydraulic head in levee (divers in boreholes)
- Permeafor CPT for hydraulic conductivity in levee
- Vegetation mapping
Kick off of the project
Launch Survey activities
Survey plan (T0)