加气混凝土试块氡射气系数随含水率及环境条件变化的研究

The variation of the radon emanation coefficient on aerated concrete blocks with respect to water content, temperature and humidity

目的研究加气混凝土试块氡射气系数随含水率、温度和相对湿度的变化规律。方法采用连续测氡仪和密闭累积腔体，测量加气混凝土试块在不同含水率（0～60％）、温度（10～40℃）和相对湿度（12％～95％）条件下的氡射气系数；并对测量结果进行回归分析，探讨氡射气系数（s）与含水率（s）、温度（T）和相对湿度的变化规律。结果加气混凝土试块的氡射气系数随着其含水率的增加呈对数型增长，8=0．096·ln（s＋2．43）＋0．037，R^2=0．952；加气混凝土试块的氡射气系数随着其温度的增加而增加，并呈线性增长关系，ε=0．00245·T＋0．0601，R^2=0．987；不同相对湿度下，加气混凝土试块的氡射气系数测量结果差异无统计学意义（P〉0．05）。结论含水率、温度变化对加气混凝土试块氡射气系数影响较大，在建材氡放射性危害评价与控制体系中应注意这些因素对加气混凝土试块氡射气系数的影响。

Objective To study the variation of radon emanation coefficient of aerated concrete blocks with respect to moisture content, temperature and relative humidity. Methods By using continuous radon measurement instrument and sealed cavity, the radon emanation coefficients were obtained in conditions of different moisture （0 - 60% ） , temperature （ 10 - 40%） and humidity （ 12% - 95% ）. The variation of radon emanation coefficients （ ε ） with respect to moisture （s） , temperature （T） and humidity were also studied by regression analysis. Results The study showed a logarithmic increase in radon emanation coefficient with the increased moisture [ε =0. 096·ln（s ＋2.43） ＋0.03,R^2 =0. 952] , a linear increase with increased temperature （ ε = 0. 002 45 · T ＋ 0. 060 1, R^2 = 0. 987） , and no significant influence on radon emanation coefficient with respect to humidity （ P 〉 0.05 ）. Conclusions Both moisture and temperature affect the radon emanation coefficient to a larger extent. Attention should he paid to both factors in the assessment and control system of radioactive hazard from building materials.