Role of real time-monitoring in slope stability
Leong, Eng Choon
Date of Issue2008
International Seminar on Civil and Infrastructure Engineering for Environmental Sustainability (2008)
School of Civil and Environmental Engineering
Rainfall-induced slope failures occur in response to climatic changes in many parts of the world. Climatic changes result in dynamic flux boundary conditions across slope surface, such as infiltration and evaporation. In addition, trees, shrubs and grass generate another dynamic process of transpiration across slope surface. As a result, stability of a slope as quantified by factor of safety is not constant over time, but varies in accordance with variation in flux boundary conditions. In other words, slopes are infrastructures whose stability is highly dependent on environment and whose failure has detrimental impacts on environment and public safety. Effect of climatic changes on slopes can be assessed using real-time monitoring. Several geotechnical instruments such as piezometer, tensiometer, inclinometer and devices for measuring changes in local climate such as rainfall gauge and weather station can be installed within the slope area. The data from these instruments are captured automatically using a data acquisition system and the data are transported to a secured website in real time using a General Packet Radio Service (GPRS). This mobile data service transfers the data using 128 kilo bytes per second (kbps) modem. The real-time information can then be processed by different public authorities to assess the impact of local climatic changes such as precipitation and evapotranspiration on stability of the monitored slopes. Warning and evacuation order can be issued once the stability of the slope approaches a dangerous level. Although the cost of installing the real-time monitoring system can be costly, the system does provide valuable information for authorities to determine the risks involved and to make an informed decision with respect to critical slopes near public facilities. In other words, real-time monitoring of critical slopes help maintain environmental sustainability of the local areas. This paper describes the procedure and the instruments used in a real-time monitoring of slopes through actual examples.
© 2008 INTERNATIONAL SEMINAR ON CIVIL AND INFRASTRUCTURE ENGINEERING 2008 FOR ENVIRONMENTAL SUSTAINABILITY.