测定低应变桩土相互作用阻尼系数的试验方法

Experimental method to determine the damping coefficient of low strain pile-soil interaction

摘要: 低应变桩土相互作用阻尼系数是进行基桩缺陷定量化分析的一个关键参数。利用瞬态激振作用时桩顶入射波与反射波之间的关系,提出了确定低应变桩土相互作用阻尼系数的方法。对砂土、粉土、粘土进行的试验结果表明,低应变桩土相互作用阻尼系数不是一个常数,它随桩侧土受到的上覆有效压力增加而增加。当桩侧土受到的上覆有效压力从30kPa增加到180kPa时,3种土的阻尼系数均增大了30%以上。同样应力条件下,砂土的阻尼系数最小,粉土次之,粘土最大。

Abstract: The damping coefficient of low strain pile-soil interaction is a key parameter to analyze defects quantitatively along piles.The new method to determine the parameter is developed using the relationship between the incident wave and the reflecting wave on the pile top under transient impact.Damping coefficients corresponding to three kinds of soils(sand,silt and clay)are determined using this method.Test results show that the damping coefficient of low strain pile-soil interaction becomes large ...