一、现行大中桥孔径计算的方法和步骤平原地区河流现行大中桥孔径计算中,对一般采用主槽平均天然流速为设计流速和所取容许冲刷系数之间是存在着矛盾的。它影响着基础的安全。为了说明这个问题,有必要把现行大中桥孔径计算的方法和步骤简单的介绍一下,这里所谈的只是一般性的,个别或特殊情 First, the current methods and procedures for large and medium-sized bridge aperture calculation Plains River Basin in the current mid-large aperture calculation, the general use of the main groove of the average natural flow rate for the design flow rate and the allowable erosion coefficient is contradictory between. It affects basic safety. In order to illustrate this problem, it is necessary to briefly introduce the methods and steps of the current aperture calculation of the Bridge. All that is said here is general, individual or special