钢筋混凝土梁循环加载时Kaiser点的确定方法

Determination of Kaiser Point in Reinforced Concrete Beam Under Cyclic Loading

对常用的几种Kaiser点确定方法进行了比较分析,从参数的选用、判断方法等方面指出了各方法的优点及不足之处。通过对钢筋混凝土梁进行循环加载试验,分析各级荷载下的AE累积计数N与荷载F关联曲线的特点,发现在ln N-F半对数坐标上,关联曲线的拐点坐标具有明显的变化规律,可作为钢筋混凝土梁循环加载时的Kaiser点;提出了用求解曲线拐点来确定Kaiser点的方法,并利用该方法对钢筋混凝土梁受荷过程的Felicity效应进行了分析。

Several methods of determining the Kaiser point are compared.Three reinforced concrete beams are cyclic loaded,and the characteristics of the N-F curves at each load levels are analyzed.It is found that the inflection points of the N-F curves in the semi-logarithmic coordinate system（ln N-F） have obvious regularity,and the inflection points can be used as the Kaiser point when the reinforced concrete beams are cyclic loaded.A new method of determining Kaiser point by calculating the inflection points is proposed and the Felicity effective of reinforced concrete beams in cyclic loading is discussed.