STABILITY OF DOLOSSE WITH DIFFERENT WAIST THICKNESS FOR IRREGULAR WAVES

摘要

Model tests were done to investigate the effect of waist thickness on the stability of dolosse under irregular wave attack. A comprehensive test programme resulted in a better understanding of dolos behaviour under a wide range of different conditions. Irregular waves with Jonswap and Pierson- Moskowitz spectra were generated using a total of four different peak wave periods. Dolosse with five different waist ratios were tested. All the dolosse had a mass of about 80 g and were placed at a "normal" packing density of = 1,00. Tests were done on three different slopes namely 1:1,33, 1:1,5 and 1:2. The test results showed that the stability of dolosse decreases as the waist ratio is increased. On average, KD-values for 2 per cent displacement of dolosse with waist ratios of 0,36 0,38, 0,40 and 0,43 were approximately 22, 51, 49 and 69 per cent respectively smaller than the Ko-value of dolosse with a waist ratio of 0,33.