公路桥梁钻(挖)孔端承和嵌岩存在的几类问题

Several Problems of Drilling End Bearing and Rock-socketed Bored Piles of Highway Bridge

通过对公路桥梁钢筋混凝土钻(挖)孔端承和嵌岩桩在设计和施工中普遍存在的问题进行分析,利用桩的分类和定义、岩石的风化及圆形桩计算方法计算桩的嵌入度,结果表明:嵌岩端承桩宜采用地层岩性、载荷类型等多要素进行分类和定义;建议按岩石饱和单轴抗压强度小于2.0MPa为界限划分;嵌岩端承桩承载力应按照单桩轴向受压承载力容许值计算;对端阻和侧阻发挥系数进行风化程度修正并不合理。

The analysis of common problems of reinforced concrete was carried out, and of drilling end bearing and rock-socketed bored piles the calculation of the embedded part of piles was conducted in terms of the classification and definition of piles, weathering of rocks and the specification. The results show that formation lithology should be considered in the classification and definition of vertical and horizontal loads of rock-socketed end bearing pile l it is suggested that the divide of saturated uniaxial compressive strength should be set at 2.0 MPa; bearing capacity of rock-socketed end bearing pile should be calculated in accordance with allowable values of axial bearing capacity; the modification of tip resistance and lateral resistance coefficient is unreasonable.