Abstract

The aim of the study is to investigate the controlling parameters of flowslide initiation experimentally through laboratory flume. Landslide is still a major frequent hazard in many parts of world despites of number of studies have been done related to slope failure. The most of slope failures are because of rainfall, as rainfall increases the moisture content and the pore pressure that reduce the shear strength of the soil. The slope after failure shows different modes, however every slope failure not produced same damages. The impact of landslide directly related to failure mode, velocity and distance travelled. There are different types of slope failure, however the flowslide is the most dangerous than other type of landslide. The flowslide type of failure occur suddenly without any warning and have fluid like motion that makes it more dangerous. In this study experiments conducted in laboratory through flume in order to investigate the parameters that initiate the flow type of failures. After the preparation of the model slope the sensors installed for the moisture content and the pore pressure. The moisture content measured with advanced sensor Imko Trime Pico-32. From the experiments it was observed that density of soil slope plays an important role in the initiation of flow type of failure. The pore pressure developed after the failure depends upon the thickness and velocity of sliding mass. The pore pressure and moisture content higher at the toe and the pore pressure higher at the base as compared to shallow depth. In the case of antecedent moisture conditions the runoff appeared at the horizontal part of the slope that erode the toe. The flowslide occur from smaller to higher depth of soil slope and significant depth of soil layer involved in flowslide type of failure. From the experiments it was observed that by installing the moisture sensors from toe to mid of the slope at the shallow depth the failure can be predicted.

Keywords:

Failure, flowslide, flume , moisture content measurements , pore pressure, rainfall, slope,

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