混凝土抗压强度回弹测试数据的分形分析

Fractal Analysis of Rebound Testing Data for Compression Strength of Concrete

分形理论在处理无规离散数据方面具有独特优点,应用于混凝土抗压强度回弹测试数据这一无规离散数据的处理时,能够得到比常规回归法更加可靠的抗压强度数据.文中通过在二维平面坐标上建立回弹测点位置-回弹值曲线(RPV曲线),采用盒维数计算法编制计算程序,得出RPV曲线的分形维数,并用来推算混凝土抗压强度.结果表明,RPV曲线分形维数与混凝土抗压强度间具有线性关系,且该法推算混凝土抗压强度可在不测试碳化深度的情况下进行,适应于大体积混凝土抗压强度的检测,为简化混凝土抗压强度的检测提供了新途径.

Fractal theory is of special merits in processing random and discrete data. When it is adopted to analyze the rebound testing data of random and discrete compression strength of concrete, much more reliable results can be obtained, as compared with the general regression method. In this paper, the Rebound Measuring Point Position- Rebound Value curve （RPV curve） on a 2D coordinate plane is established, and the box-dimension calculation method is adopted to design a calculation program to obtain the fractal dimension of the RPV curve and to calculate the compression strength of concrete. The results show that there is a linear relationship between the fractal dimension of the RPV curve and the compression strength, and that the proposed method can calculate the compression strength without testing the carbonation depth. Moreover, it suits the compression strength testing of concrete with big volumes and thus offers a new simplified approach to the detection of the compression strength of concrete.