全球定位系统和常规仪器远距离边坡监测及预报系统的应用

Abstract

介绍了最近由香港理工大学开发的边坡自动化监测系统,阐述了该监测系统在实际边坡的监测中的有关问题。监测结果表明,该系统使用方便,工作稳定可靠,可实时监测到边坡的一些重要参数,进而用来预测边坡的稳定状况。 Landslides in Hong Kong and in other countries and regions pose a great danger to human life and property. In Hong Kong, many buildings, factories and important facilities are either very close to or on the hillside. During a landslide, life and property may be at risk. Therefore, any pre-warning of slope failure will allow time for people to evacuate and take other preventive measures. Many landslides in Hong Kong have a deep-seated slip and noticeable displacement may occur prior to failure. Sometimes, the landslide is progressive in nature. It is possible to forewarn a landslide by monitoring any pre-failure displacement. Therefore real-time slope monitoring may potentially play an important role in landslide warning and prevention. An automated integrated slope monitoring and warning system has been developed by the authors in Hong Kong. The integrated system consists of (a) a conventional slope monhoring-warning package and (b) a multi-antenna Global Positioning System (GPS) package. The conventional package includes (i) in-place inclinometers, (ii) piezometers, (iii) rain gauges and (iv) a Time Domain Reflectometcr (TDR). The multi-antenna GPS package is a special technology newly developed for monitoring surface movements of a slope. The integrated system has a remote data acquisition/control unit connecting an office computer to a data-logger at the site for both the conventional package and the GPS package separately for data communication and control with visual software. In this approach, the two packages can work jointly or independently to monitor a slope. When working together, the two packages are set up at the same slope site and used to collect data of sub-surface ground movements, pore water pressures, rain falls, surface ground movements. The data from the two packages are then transferred to the same office computer, processed and analyzed together. The integrated data can be automatically retrieved, temporarily stored and transmitted from the two packages. Software can perform data download, storage, analysis and real-time display. All data from the two packages are integrated and analyzed using a database developed by the authors. The integrated system was installed to monitor a full-scale test at loose-fillslope site at the Kadoorie Agriculture Research Centre, Hong Kong, from April 2002 to November 2002. The slope was loaded to failure. The system monitored the entire slope loading and failure process and collected valuable data. The analysis of data has shown that the integrated system is reliable, accurate and effective for monitoring slope movements and warning of any potential slope failure.