高精度动态监测水灰比的核密度计的研制及其应用

来源期刊：中南大学学报(自然科学版)2004年第4期

论文作者：徐力生 陈伟 彭环云 徐蒙

文章页码：647 - 650

关键词：水灰比;密度计;γ射线;动态检测

Key words：water cement ratio; densimeter;γ-ray; dynamically monitoring

摘    要：研制了高精度动态监测水灰比的核密度计。核密度计的监测原理是:高能γ射线束穿过水泥浆液时,一部分射线被浆液吸收,另一部分射线穿过浆液被探测器吸收,并转化为电信号,经放大、分析后被记录。由于浆液中水和水泥颗粒对γ射线的吸收系数不一样,所以探测器接收信号的强弱不同,在确定射源强度、射线探测器和待测浆液厚度的基础上,得出浆液密度与γ射线透射计数的自然对数lnN呈线性关系,通过现场标定可求出线性方程的斜率μ,通过数学模型可以计算出浆液密度和水灰比。研究结果表明:测量值不受浆液的流速、压力、温度、粘度、腐蚀等因素的影响;探测部分可安装在灌浆工程施工现场,在高温、潮湿、高灰尘的恶劣环境中,仪器能正常工作。

Abstract: A nuclear densimeter of monitoring water cement ratio was studied based on the principle is that when high energyγ-rays pass through cement grout, one part of rays is absorbed by cement grout and the other part of rays passing through cement grout is absorbed by locator, which is conversed into telecommunication and recorded after being enlargment and analysis. Sinceγ-rays absorption coefficients of water and cement are different, the telecommunication absorbed by locator is different. According to rays intensity, ray-locator and cement gout thickness, it is shown that the cement grout density has linear relationship with nature logarithm lnNof rays that pass through cement grout. The shopeμcan be determined after calibration on the spot and the water cement ratio mathematics model.The measured values are not affected by cement gout current velocity,pressure, temperature, viscosity, corrosion,etc. The locator can be installed on the spot in grouting engineering and the instrument can work normally under high temperature, damp and dust environment.