【摘要】 波浪作用下海底斜坡滑动稳定性分析中,一般未考虑海底坡度引起的波浪浅水效应,即不考虑波浪在斜坡面上的变形导致的波压力变化,降低了其计算结果的可靠性。本文基于沿斜坡面传播的线性波浪理论,考虑波浪的浅水效应,利用波浪与重力作用下海底斜坡的有效应力场,计算海底斜坡滑动稳定性安全系数。在验证海底斜坡滑动稳定性计算结果可靠性的基础上,分析了坡度对海底斜坡瞬态波浪响应及其滑动失稳特征的影响。结果表明,由于波浪沿斜坡面传播的浅水效应,相对于水平海床,波浪作用下斜坡最大瞬态应力和孔隙水压力随着坡度的增加基本呈线性增加趋势,最大水平位移呈非线性增加趋势;相比于坡底水平段海床的滑动区,斜坡面上滑动区的深度和水平方向滑动范围均有所增加,且坡度越大,这种效应越显著;相比于饱和海床,非饱和条件下,坡度对斜坡体滑动特征的影响程度有所降低。更多还原

【Abstract】 For instability analysis of submarine slopes under waves, slope-induced wave shoaling is generally not considered, that is, variation of the wave pressure on sloping seabed caused by wave transformation is not considered, which reduces reliability of the calculated results. Based on the linear theory of wave propagation along gentle sloping surface, taking wave shoaling into account, factor of safety of submarine slope is calculated using the effective stress of soils under waves and gravity. Based on the verification of results of submarine slope instability, the effect of slope gradient on oscillatory seabed response and the sliding characteristics of submarine slopes is analyzed. It has been shown that compared to the flat seabed, the maximum periodic shear stress and pore water pressure increase linearly with the increase of slope angle due to wave shoaling along sloping surface. Compared with sliding area of flat seabed at the bottom of the slope both, the sliding depth and horizontal range in sloping area increase, and the larger the slope angle, the more obvious the increase. Compared with the saturated marine soils, the slope gradient has less influence on sliding characteristics of unsaturated submarine slopes.更多还原