【摘要】 我国各部门的设计规范和规程中,对钢筋混凝土受弯构件使用阶段带裂缝工作的截面刚度Bd长期来均沿用三系数的计算公式。本文在钢筋轻骨料混凝土受弯构件三系数刚度计算公式的基础上,通过理论推导和200多根试件的分析提出了适用于各种不同截面形式的甚为简明的刚度简化计算公式。它不仅和三系数刚度计算公式具有同样的精度,而计算要简便得多,并能看出各影响参数与刚度Bd间的直接的定量关系,对迅速合理地进行结构截面设计具有较大的实际意义。本文所提出的刚度简化计算公式已被钢筋轻骨料混凝土结构设计规程(JGJ12-82)所采纳。更多还原

【Abstract】 In design Codes and Specifications drawn up by various department of our country,the complex expression based on the three-coefficent approach is still used to calculate the stiffness Bd of cross section in R.C flexural members with cracking under short-time loading.In this paper a simplified formula of flexural stiffness for the various types of section has been presented.It is obtained by means of theoretical derivation based on stiffness expression of three-coefficient for reinfored lightweight aggregate concrete and analysis of test data of more than 200 specimens.The formula not only has the same accuracy as that of the three-coefficient approach,but also needs less computional efforts and is simpler than the latter.Moreover,it can directly indicate the quantitative relations between the stiffness Bd and each of influence parameters.So the formula will have a great practical significance in designing cross sections of flexural elements.The formula has been adopted in the Reinforced Lightweight Aggregate Concrete Design specification (JGJ12-82)of our country更多还原