体积膨胀法测量加气混凝土开孔隙度的研究

关键字：加气混凝土,开孔隙度,体积膨胀法

（1.清华大学 工程物理系，北京  100084；2.中国建筑材料检测认证中心有限公司，北京  100024；3.中国疾病预防控制中心 辐射防护与核安全医学所，北京  100088）

    摘要：采用体积膨胀法测量加气混凝土砌块的开孔隙度，研究了测量压力、样品尺寸等对开孔隙度的影响，以及其它实验操作条件及参数的选择。结果表明：加气混凝土砌块不同位置开孔隙度存在差异，离散系数在0.3%~0.4%之间；开孔隙度与实验压力呈显著负相关，但压力的影响小于位置差异的影响，综合考虑误差和实验耗时等因素，选择60 kPa作为实验压力进行开孔隙度测量；切割对开孔隙度测量值的影响较小，这有利于证明小样品的开孔隙度测量值可以代表砌块本身。建立的体积膨胀法可以高效、准确地测量加气混凝土的开孔隙度。
    关键词：加气混凝土；开孔隙度；体积膨胀法
    中图分类号：TU528.2        文献标识码：A        文章编号：1001-702X（2017）04-0078-05

Measuring open porosity of aerated concrete by volume expansion method
　　WANG Junlin1，ZHU Li1，LI Guiqiang2，CUI Hongxing3，SHANG Bing3，WU Yunyun3
（1.Department of Engineering Physics，Tsinghua University，Beijing 100084，China；2.China Building Material Test and Certification Group Co. Ltd.，Beijing 100024，China；3.National Institute for Radiological Protection，Chinese Center for Disease Control and Prevention，Beijing 100088，China）

    Abstract：Volume expansion method is designed to measure the open porosity of aerated concrete block. The influence of measuring pressure and sample size on the open porosity as well as the test operating conditions and the selection of parameters are studied. The results show that，there is difference of open porosity among different locations of block. The coefficient of dispersion varies between 0.3% and 0.4%. It is significantly negative correlation between the pressure and the open porosity，while the pressure has less influence on the open porosity than different locations of block，and 60 kPa is perceived as the best pressure for open porosity measurement in considering relative standard deviation and experimental period，the value of open porosity is insignificant with cutting process，thus，the measurements of open porosity can represent block itself. In short，volume expansion method can accurately and efficiently measure open porosity of aerated concrete.
    Key words：aerated concrete，open porosity，volume expansion method