论文部分内容阅读
以舟山海域海底原状海相软土为研究对象,利用GDS共振仪对各深度范围土样在不同围压下进行了一系列动力试验,得到了各深度范围土样在不同围压下动剪切模量和阻尼比随动剪切应变的变化趋势。试验结果表明:1×10-6~1×10-2应变范围内深度对舟山海相软土动剪切模量和阻尼比的影响不太明显;随着动剪应变的增加,动剪切模量逐渐衰减,阻尼比逐渐增大;围压对动剪切模量比G/Gmax和阻尼比D/Dmax的影响比较明显,围压越大G/Gmax越大,阻尼比D/Dmax越小。通过理论分析采用修正的Hardin-Drnevich模型给出其归一化动剪切模量比和阻尼比随剪应变变化关系曲线,并且给出了舟山海域海相软土G/Gmax和D的推荐值以及与规范值、袁晓铭推荐值加以比较。试验及分析结果加深了对舟山海域海相软土动力特性的认识,也进一步为海洋底盘工程建设提供了可靠的动力学参数。
In this paper, a series of dynamic tests were carried out on the soil samples of different depths under different confining pressures using GDS resonance instrument. The dynamic shear tests were carried out under different confining pressures Modulus and damping ratio with the dynamic shear strain trends. The experimental results show that the influence of depth of 1 × 10-6 ~ 1 × 10-2 strain on the dynamic shear modulus and damping ratio of Zhoushan marine soft soil is not obvious. With the increase of dynamic shear strain, dynamic shear The modulus gradually decays and the damping ratio increases gradually. The effect of confining pressure on dynamic shear modulus ratio G / Gmax and damping ratio D / Dmax is obvious. The bigger the confining pressure is, the larger G / Gmax and the damping ratio D / Dmax small. Through the theoretical analysis, the modified Hardin-Drnevich model is used to give the normalized dynamic shear modulus ratio and the damping ratio as a function of shear strain. The recommended values of G / Gmax and D for marine soft soil in Zhoushan sea area are given And with the standard value, Yuan Xiaoming recommended values to be compared. The results of the tests and analysis deepen the understanding of the dynamic characteristics of marine soft soil in Zhoushan sea area, and further provide reliable kinetic parameters for the construction of marine chassis.