EFFECT OF DIKE SLOPE ON THE DEVELOPMENT OF MATRIC SUCTION AND VOLUMETRIC WATER CONTENT DURING OVERTOPPING TESTS

The infiltration of water flow inside soil particles has a serious effect on dike stability. It causes increasing in water content inside soil particles and thus breach channel is initiated inside dike crest and body during overtopping failure. In this study, the evolution of matric suction and volumetric water content are discussed during spatial overtopping tests. The overtopping tests are conducted in small flume channel in Hydraulic Geotechnical laboratories at the Universiti Sains of Malaysia. Two dike slopes of 1:3H and 1:2.5H for both upstream and downstream slopes are constructed under constant inflow discharges of 30L/min. The results show that the saturation process decreases and increases matric suction and volumetric water content, respectively for both dike slopes. The saturation process of water content is faster for 1:3H than those for 1V:2.5H prior to overtopping failure while it is higher in latter slope than in previous one after the initiation of breach failure