unjab has highest percentage of area under the canal and river network. The scarcity of land to develop road network has forced the road construction agencies to move towards the canal and river banks where roads can be constructed comparatively easily being the provincial government land by saving a lot of land acquisition cost. The performance of a road built on canal bank is always remain uncertain. The most of the canals and rivers passes through the alluvial planes, to keep the cross section of canal uniform a constant water level and bed slope is maintained, this necessitating the construction of fall structures and high side banks. The effect of capillary and water supply level always keep the Phreatic line moving up and down. The flowing water exerts the pressure on sides of canal banks thus increasing the stability, during drawdown,on one hand this pressure decreases, the pore water pressure creates rapid drawdown condition This rapid draw down along with vehicular load in rainy season put whole embankment and pavement structure into a vulnerable situation, as the factor of safety against slope failure comes well below below to unity. In this study effort has been made to find the effect of these forces on the stability of canal banks so that some precautionary measures can be adopted during such critical period. In this study four different conditions are tested. Condition No 1 Dry condition, when there is no rain and canal is also dry, most likely condition at the time of construction of canal. Condition No 2 Wet Condition at Full Supply Level (FSL), rainy weather condition when there is a long spell of rains and canal is running at Full Supply Level. Condition No 3 Rainy weather condition when there is long spell of rains and canal is running at Lowest Water Level (LWL). Condition No 4 Rainy weather condition when there is long spell of rains and canal is running at Lowest Water Level (LWL) and additional surcharge of traffic load is considered to create worst service life conditions for road pavement. The embankment material is tested for its in-situ properties, the Standard Penetration Test (SPT) is conducted to draw the profile of canal embankment layers and location of phreatic line at various stages of water supply level in dry as well as rainy seasons. SLOPE/W, a software developed by GEO-SLOPE International Canada, is used for slope stability analysis.
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