岩溶地基岩质单元的划分依据及fr的确定

BASIS FOR DIVIDING KARST FOUNDATION ROCK'S QUALITY UNIT AND AFFIRMING ITS BEARING CAPACITY (FR)

根据岩心观察与描述，岩心采取率、岩石质量指标（Ｒ、Ｑ、Ｄ）、岩石的块度指标、声波值及声波曲线、岩体回弹检测等方法确定岩体的完整性。结合岩体风化、溶蚀、地质构造背景正确地划分岩体的岩质单元。同时采用岩石单轴抗压强度试验、点荷载试验、静载荷试验等方法按单元提供各岩质单元地基承载力的标准值（ｆｒ）。实践证明，通过上述方法，尤其是静载荷试验后，地基承载力比经验数据或其它方法间接确定的承载力有较大幅度的提高。

This paper affirms the completeness of rock mass by observing and describing the rock core,recovery ratio,R.Q.D.,the percentage of rock-fault,sonicwave value and sonicwave diagram and measuring the rebounding of rock.The rock quality unit of the rock mass is properly divided according to its decomposition,dissolution and tectonics.At the same time,per unit foundation bearing capacity (fr) is provided by testing uniaxial compressive strength,point loading,static loading and so on.It is proved that the foundation bearing capacity obtained in this way,especially by static loading test,is greatly improved in comparison with the experienced data and the results of any indirect methods.