强夯加固地基的土体竖向位移计算方法研究

Simplified calculation method of soil vertical displacement under dynamic compaction

根据动力分析中应力边界与速度边界之间的关系,将应力边界时程转化为速度边界时程,提出计算土体竖向位移的新方法,并进行了简化和多角度对比性研究。在钱家欢加卸载模型应力和竖向位移计算的基础上,提出将正弦荷载形式和三角形荷载形式分别引入,推导出竖向位移的两种简化计算方法。两种方法概念清楚、物理意义明确,形式简单且相同,区别仅在于系数不同。工程实例表明,两种方法计算出的竖向位移均接近于实测位移,但正弦荷载形式下的位移计算方法更能反映实际情况。

According to the relationship between stress boundary time-history and speed boundary time-history in dynamic analysis,stress time-history of dynamic boundary condition is transformed into speed time-history.A new method to calculate soil vertical displacement is proposed,for which simplified and multi-angle comparison study is done.On the basis of stress and vertical displacement calculation in Qian Jiahuan’s model,sine load and triangular load forms are introduced;and two simplified calculation methods of vertical displacement are derived.Two methods are clear and simple and the same,except the difference in coefficients.The engineering example shows the vertical displacements calculated by two methods are close to the measured displacements,but the displacement method under the sine load is better to reflect the actual situation.