论文部分内容阅读
将土体视为液固两相多孔介质,利用连续介质力学得到了饱和土层的水平动力阻抗,将上部结构视为梁单元,桩-饱和土-桩之间的动力相互作用借助于等效的Winkler动力弹簧和波的干涉来模拟,并通过承台处力的平衡将群桩和上部结构耦合起来,研究了简谐SH地震波作用下饱和土-桩-上部结构的动力相互作用问题。以2×2群桩为例,对饱和土-桩-上部结构体系进行了数值分析,讨论有关参数对结构体系动力特性特别是抗震性能的影响。数值分析表明,桩间距、桩-土弹性模量比、长径比等对结构体系的抗震性能有较大影响。桩间距对地震放大系数的影响与外界激励的频率有关,桩土模量比较小、结构和桩基的阻尼较大时结构体系的抗震效果较好,长径比越大地震作用下产生的结构变形越大。
The soil is regarded as a liquid-solid two-phase porous medium, the horizontal dynamic impedance of saturated soil is obtained by means of continuum mechanics, and the superstructure is considered as beam element. The dynamic interaction between pile-saturated soil- The Winkler dynamic spring and wave interference are used to simulate the interaction between pile groups and the superstructure through the force balance of the caps. The dynamic interaction of saturated soil-pile-superstructure under simple harmonic SH seismic waves is studied. Taking 2 × 2 pile groups as an example, the numerical analysis of saturated soil-pile-superstructure system is carried out, and the influence of relevant parameters on the dynamic characteristics of the structural system, especially the seismic performance is discussed. Numerical analysis shows that the pile spacing, pile-soil elastic modulus ratio, aspect ratio and so on have a great influence on the seismic performance of the structural system. The effect of pile spacing on seismic amplification factor is related to the frequency of external excitation. The pile-soil modulus is relatively small, and the anti-seismic effect of the structural system is better when the damping of the structure and the pile foundation is larger. The larger the aspect- Larger deformation.