Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Know-how Researching natural hazards with the help of METTLER TOLEDO products It can’t be denied anymore: Global climate change is a reality. Until recently, it seemed to be just another doomsday scenario promoted by crazy environmentalists. But the alarming truth of global warming is now recognized by a variety of interest groups worldwide. And the recently published UNO Climate Report backs their views with historical facts. Switzerland, 2002. One of the more visible effects of climate change in the recent past has been the high number of extreme weather incidents. A good example is the extraordinarily heavy rainfall over the last few years that has caused so many floods and landslides – including right here in Switzerland. The influence of climate on the stability of embankments is now being studied by the Technical University of Rapperswil (HSR) in cooperation with Nanyang Technological University (NTU) in Singapore. What are they studying? The landslide model is being used to study the level of impact of climactic changes on the stability of hillslopes. In this study, scientists are particularly interested in the reaction of the capillary forces in the soil on the intensity and duration of precipitation, as well as previous rain events. The groundwater flow within a hillslope is considered to be another stability factor. The stratigraphical arrangement of the soil influences the groundwater flow through more or less permeable rock beds. Groundwater simulations were conducted to study this action more closely. Measurements The landslide model is a 2.00 x 0.60 x 1.80m box made of steel and acrylic panels with a model hillslope. The rain unit installed in the cover can be operated with different intensities, while the groundwater is directed over clefts on the face of the wall and behind it. The slope of the model can also be set using an hydraulic cylinder. 11 Landslide Bormio, Italy, 1987 Bavaria, Germany, 1988 of the pore pressures and the water content immediately before a landslide yield information about the fracture behavior of an embankment. Scales and data transfer software from METTLER TOLEDO Groundwater and surface run-off is continuously recorded using METTLER TOLEDO scales. With the BalanceLink software, also from METTLER TOLEDO, these scale values are then directly transferred to a computer and simultaneously filed in an Excel table. Later in the study, piezometers will monitor the flow of the water table. Tensiometers will be used to measure the pore water pressure in the soil at several measuring points, and data loggers will send the data to the computer. The water content will also be measured using time domain reflectometry (TDR) and the data likewise transferred to the computer. The goal of the research project is to make more precise predictions regarding future landslides. A key benefit will be the ability to warn the populations of high-risk areas earlier and more effectively. www.mt.com For more information Mettler-Toledo AG CH-8606 Greifensee, Switzerland Phone +41-44-944 22 11 Fax +41-44-944 30 60 Subject to technical changes, © 04/2007 Mettler-Toledo AG, MarCom Industrial