深圳龙岗中心花园填土地基强夯加固效果及承载力的确定

通过对一代表性强夯处理填土基实例强夯前后地基加固效果的对比分析，发现低能量区填土层的加固效果稍优于高能量区填土层的加固效果，一定的深度内，在相同的夯击能力作用下，厚度较小的填土层的加固效果稍优于厚度较大的填土层加固效果。对于这一与通常人们认知有所不同的现象，运用波的反射透射理论进行了解释；填土层下伏硬层的存在及埋深的大小，是引起强夯加固效果差异的主要因素，通过对强夯地基各种测试方法确定的承载力与载荷试验结果进行对比分析，认为用于确定一般自然沉积土的承载力的常规方法不适用于夯夯地基土，根据标贯试验击数与载荷试验结果之间存在的相关关系，提出了根据标贯试验击数确定强夯地基土承载力的经验公式，fk=0.4N^2 6.0N。

Study on effect of heavy tamping with different energy impact o n fill foundation and the determination of bearing capacity of tamped soil o n Shenzhen Longgang Garden site

By comparison of the improving effect of heavy tamping in a representative fill foundation before and after heavy tamping, it is found that the improving effect of the fill tamped with lower energy is slightly better than that with higher energy, and the improving effect of the thinner fill is slightly better than that of the thicker fill in the same tamping energy area. This phenomenon is explained by wave propagation theory. It is thought that the harder layers beneath the fill are the main factors causing the differences of improving effect on this site. Through the comparison between the bearing capacity of tamped soil determined by different testing methods and that determined by load-bearing test, it is concluded that the general methods to determine the bearing capacity of the natural soil is not fit for determining that of the tamped soil.An empirical formula is proposed as: f k=0.4N 2+6.0N?