Tritium penetration through concrete
Tritium penetration through concrete
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氚穿透混凝土
DOI：
10.1016/0956-053x(89)90064-0
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发表时间：
1989
期刊：
影响因子：
8.1
通讯作者：
C. A. Hazin
中科院分区：
文献类型：
--
作者：
G. Eichholz;W. Park;C. A. Hazin
混凝土是许多拟议的低放废物储存设施中迁移的主要障碍。虽然它可能会在不同程度上阻碍一些溶解的离子，但尚不清楚氚在混凝土中的移动会在多大程度上发生。为了测量氚的迁移率并确定其对混凝土性能和环境参数的依赖性，在一系列高矿渣骨料混凝土圆柱体上进行了氚示踪实验，结果发现，无涂层混凝土吸水非常迅速，一旦润湿，水中氚的传导率约为8 × 10− 4cm 3/cm 2天。对于厚度超过10 cm的厚试样，氚的迁移完全取决于孔隙度和导水率。通过表面处理、在骨料中使用较小的石料尺寸和振动压实可以降低扩散速率。静水可以提供一个静压头，使流速有所增加，但它也受到水力传导率终端值的限制，除非混凝土墙以某种永久性的方式进行涂层或浸渍，否则混凝土墙作为含氚液体的阻滞屏障似乎没有什么作用。
Concrete represents the primary barrier to migration in many proposed low-level waste storage facilities. While it may retard some dissolved ions to varying extent, it is not clear to what extent tritium movement through concrete would take place over extended periods. Experimental tests have been performed, with tritium as a tracer, on a series of concrete cylinders of a high slag aggregate composition to measure tritium mobility and to determine its dependence on concrete properties and environmental parameters.It was found that uncoated concrete absorbs water quite rapidly and once wetted, conducts tritium in water at a rate of about 8 × 10−4cm3/cm2day. For thich specimens, over 10 cm in thickness, tritium movement is solely determined by porosity and hydraulic conductivity. Diffusion rates can be lowered by a surface finish, by using a smaller stone size in the aggregate and by vibratory compaction. Standing water may provide a hydrostatic head that results in some increase in flow rate, but it too is limited by the terminal value in hydraulic conductivity.Unless the concrete wall is coated or impregnated in some permanent fashion, it appears that little credit can be taken for the concrete walls as a retarding barrier for tritium-bearing liquids.