循环孔隙水压力作用下饱和砂土变形的试验研究

Experimental study on deformation of saturated sand under cyclic pore water pressure

波浪荷载的作用会在近海砂体基础中产生循环孔隙水压力,研究循环孔隙水压力作用下砂床土体的力学行为对海岸和近海工程有重要意义。本文选用福建标准砂为研究对象,自动控制水压力发生装置作为动力源,通过固结不排水三轴试验,研究分析了在循环孔隙水压力作用下影响饱和砂土变形性能的试验参数。试验结果表明,当固结应力比、频率较大,而相对密度较小时,试样有较大的变形,更容易发生破坏。最后,绘制了试样轴向应变与动孔隙水压力系数的关系曲线,并分析了曲线的变化规律。

Cyclic pore water pressure could be produced by the action of the wave load in the offshore sand foundation. It was very important for coastal and offshore engineering to study the mechanical behavior of sandy soils under the action of cyclic pore water pressure. Based on the results of consolidated undrained triaxial tests on Fujian standard sand, the parameters, ratio of consolidation stress, relative density and frequency, were studied, and they obviously affected deformation of saturaled sand under cyclic pore water pressure produced by water pressure controlling instrument. The experimental results indicated that the specimen had a large deformation when the ratio of consolidation stress and frequency were larger and the relative density was smaller. Finally, the curves of axial strain and dynamic pore water pressure coefficient were figured and analyzed.