Study on monitoring and numerical analyses of groundwater variation and inclinometer displacement induced by heavy typhoon rainfall

Abstract. This study examined the slope area of the Huafan University campus, within the entire Ta-Lun Shan area. Situated at 550 m above sea level, the area is geographically classified as a dip slope. For sustainable development of the campus, a variety of continuous monitoring equipment has been set. This study continues to analyze the monitoring data in the previous period, but focuses on the observation and comparison of the horizontal displacement at different depths recorded by inclinometers with time. At the same time, the relationship between the groundwater variation caused by heavy typhoon rainfall and the driven deep displacement of the slope is studied. In addition, this study has also been extended to the whole Ta-Lun Shan area, the observation data of cracks inside and outside the campus are analyzed. The displacement and sliding data collected over the years by the inclinometers are used to study the potential sliding surfaces distribution of the slope, combined with the influence of the typhoon rainfall. This study also continues to obtain the relationship between groundwater level and rainfall, such as the time lag and groundwater level changes, and reviews the effectiveness of the implementation of two catchpits at the campus. In the process of renovation, a Shape Acceleration Array (SAA) is used for measuring the instantaneous displacement to monitor if the displacement has increased during the implementation of the catchpits. The SAA measurement is taken as the reference basis for hazard prevention and maintenance of the slope, thus reducing and preventing the occurrence of disasters in the area. Then, a series of shear tests are carried out. Finally, the software Geostudio is applied to analyze the relationship between rainfall infiltration, groundwater level, and the displacement of the entire slope. The numerical analysis results are compared with the monitoring results in order to comprehensively discuss the slope safety.