论文部分内容阅读
针对动冰载作用下桶形基础周围土体的液化变形进行了数值模拟。建立饱和砂层中桶形基础的简化计算模型,研究动载作用下砂层竖向和水平向的液化变形。首先与桶形基础动载离心机试验比较,验证了计算模型的可靠性。分析了砂层竖向和水平向液化变形特征,以及砂层变形随动载特性和土性参数变化的规律。研究结果表明:砂层变形随着动载频率减小、振幅加大、砂层弹性模量降低而增大。在该文计算模型和荷载条件下,砂层竖向最大变形发生在距荷载作用边界0.25倍桶高位置处,水平最大变形发生在荷载作用边界处。当动载激振时间超过5h后,土顶面竖向变形约为土底面竖向变形的3倍,距荷载作用边界2.0倍桶高位置处的水平变形仅为荷载作用边界处水平变形的3.3%。
Aiming at the liquefaction deformation of soils around the bucket foundation under dynamic ice loading, numerical simulations were carried out. A simplified calculation model of the bucket foundation in saturated sand was established to study the vertical and horizontal liquefaction deformation of sands under dynamic loading. First of all, compared with the bucket foundation dynamic centrifuge test, the reliability of the calculation model is verified. The characteristics of vertical and horizontal liquefaction deformation of sand and the law of deformation of sand layer with the dynamic load characteristics and soil parameters are analyzed. The results show that the deformation of sand layer increases with the decrease of dynamic loading frequency, the increase of amplitude and the decrease of elastic modulus of sand layer. Under the computational model and loading conditions, the maximum vertical deformation of the sand layer occurs at a height of 0.25 times the barrel boundary of the load and the maximum horizontal deformation occurs at the boundary of the load. When the dynamic excitation time exceeds 5h, the vertical deformation of soil top surface is about 3 times of the vertical deformation of soil bottom surface. The horizontal deformation at 2.0 times the barrel height from the load effect boundary is only the horizontal deformation at the load boundary %.