用曲线积分计算桥梁正截面承载能力

Bearing capacity of normal section for bridge calculated by curvilinear integral

桥梁混凝土构件以前用的电算办法是节线法 ,这在结构计算程序与CAD程序是分开来时是合适的 ,如果CAD程序与结构计算程序合为一体时 ,CAD程序的几何元素是用参数法 ,对于直线记录的是起点和终点 ,而圆记录的是圆心、半径、起点、终点 (或起始角、终止角 ) ,要变成节线格式需要人工转换很繁琐 .

The method in computer clsed before is the method of nodal line. The method is appropriate if the computing procedure is separate from CAD procedure. But if they are integrative the method isn't appropriate. It is parameter method in Computer aided design (CAD) procedure, in which straight line is showed by initiative point and end point, arc is showed by the center of circle, radius, initial and end points. It is very complicated to transform them into nodal lines. A method which can directly compute the bearing capacity of the section according to parameter equation by Green Formula is put forward.