β射线辐射对建筑石膏强度的影响

建筑石膏粉经250～500kGy剂量β射线辐射后,颗粒微观形态规整度提高,粒径在50.9～62.6μm的颗粒比例减少了24%,几乎没有粒径大于62.6μm的颗粒。SEM图像表明,经辐射后,建筑石膏粉中有尖锐棱角的颗粒减少,片状颗粒与针状颗粒比例减少,柱状颗粒与粒状颗粒比例增加。参照GB9776-88制成标准样进行强度测定,试块的抗折强度比原来提高了22%～30%。

Study on Influence of β-ray Radiation for Flexible Strength of Building Gypsum

The results concerning the influence of β-ray radiation for the gypsum were presented. After β-ray radiation, the overall form of the gypsum particles was much more regular and the particles of 50.9～62.6 μm were reduced by 24%, and there was nearly no particles larger than 62.6 μm. The morphology of the gypsum particles and the set gypsum was studied by scanning electron microscopy. The SEM images showed that the radiated gypsum particles had fewer particles with sharp edges;the proportion of needle-like particles and sheet particles was reduced;the proportion of cylindrical particles and granular particles was increased. The results showed that the flexible strength of the standard set gypsum made of radiated gypsum particles was increased by 22% to 30%.