Authors

Monitoring Analysis and Simulation Experiments of the Effectiveness of Water-Collection Wells

T. C. Yi, C. J. Jeng*, and C. C. Chen

All-Wisdom Engineering Consulting Co., Ltd.

ABSTRACT

To evaluate the effectiveness of the catch pits, the slope displacement and groundwater condition before and after the construction of the catch pits are compared through analyses of monitoring data and numerical simulations. The results show that the groundwater level drops by about 10m after the installation of the catch pits. In addition, the rainfall threshold for the rise in groundwater level increases and the time required for the groundwater to return to the normal level decreases. These impacts have led to an increase in the rainfall threshold value (by at least 70%) for causing the slope displacement. On the other hand, the simulation results reveal that the influence of catch pits is more distinct for the case of heavy rainfall (compared to the case of drizzle), as the groundwater can be effectively drained and the infiltration rate is significantly lowered. Moreover, the rainfall-induced slope displacement as predicted by the simulations is very close to the actual displacement. In this study, the rainfall threshold values for different displacement levels of Ta-lun slope land are developed which can serve as references for subsequent slope management.

KEYWORDS: slope monitoring analysis, shape accel array(SAA), catch pits