受弯构件正截面基本方程及在评估中的应用

The Basic Equation of Flextural Members and Its Use in Evaluation

以平均截面平衡方程和变形方程为基础，研究了短期和长期荷载下裂缝特征值，即平均裂缝宽度与平均裂缝间距之比，得出了简化计算模式．分析了裂缝特征值、荷载和截面配筋率的相互关系，提出了通过构件外部特征（裂缝），评估受弯构件可靠性的简捷方法．

Based on the equilbrium equation and geometrical equation of the equal section,the crack feature,that is, the even crack width over the even space of crack,under short-period load or sustaind load is analyzed and a simple model is advanced.The relation between the crack feature,the load and the steel ratio is also studied based on the basic equation. A simple reliability evaluation method usingcrack message of flextrual members is presented.