一、问题的提出 从钻孔灌注桩发展成为桥梁基础的一种常见的重要的基础型式以来,对于具有圆形截面的桩身材料强度的计算,日益成为共同关心的问题。在现行计算方法的基础上,为了简化繁复的试算过程,有的单位编制了辅助计算用表,有的编制了辅助计算图,达到了简化计算的目的。但是,在实践中,我们发现,现行计算方法,由于理论上的原因,仍然存在一些值得探讨的问题: I. PROBLEM PROBLEMS Since the development of a bored pile as a common and important foundation for a bridge foundation, the calculation of the strength of a pile body material with a circular cross section has increasingly become a matter of common concern. On the basis of the current calculation methods, in order to simplify the complicated trial calculation process, some units have compiled the auxiliary calculation tables and some have compiled the auxiliary calculation charts, thus achieving the purpose of simplifying the calculation. However, in practice, we find that there are still some problems to be discussed for the current calculation method, for theoretical reasons: