用MT4090 LCR测量仪检测水泥砂浆裂缝的试验研究

Investigation on Crack Detection to Cement Mortar by MT4090 LCR

以预设不同尺度裂缝的水泥砂浆块体和无裂缝水泥砂浆块体等3组试件为试验研究对象,提出利用MT4090 LCR测量仪直接测试试件的复阻抗幅模z和相角φ、等效串联电阻ESR和电容Cs,并与基于交流阻抗谱法得到的测试数据进行比较。试验研究表明:基于交流阻抗谱法和用MT4090 LCR测量仪得到的数据非常接近,具有同样的规律和特征;有裂缝的水泥砂浆试件的z、ESR值明显大于无裂缝水泥砂浆试件,且随裂缝长度增大而增大,Cs值变化规律相反,这3个参数可以作为裂缝检测及监测的测试参数;用MT4090 LCR测量仪有望真正实现快速、简便的混凝土裂缝的检测与实时监测;验证了水泥砂浆试件呈现电容性,且容抗值相对ESR值较小。

Nine cement mortar specimens with or without crack were designed to be tested for the data of impedance amplitude(z) and phase angle(φ),equivalent series resistance(ESR) and capacitor(Cs) by MT4090 LCR.The results were compared with that by AC impedance spectroscopy testing technology.Results showed that the data of each parameter measured by AC impedance spectroscopy testing technology are similar to those by MT4090 LCR.The impedance amplitude,equivalent series resistance,and capacitor for the specimens with or without crack are quite different from one to another,so these three parameters can be used as the intrinsic property of cement mortar in the crack detection.The rapid method of crack detection to concrete may come true by MT4090 LCR.Furthermore,this experimental study validated that the cement mortar is capacitive as well.