An innovative apparatus guided by a proposed theoretical-model was developed for evaluating the radial gas-permeability of cement-based materials under steady-state flow. The testing condition is of higher inlet-gas pressure in an annular concrete cavity to monitor the pressure decrease over time. The gas-tightness for the cavity was effectively enhanced and quantitatively characterized by an ingenious silicone-rubber washer with embedded flexible sensors. The radial gas-permeabilities of the annular concrete with different water-to-cement (w/c) ratios of 0.35–0.55 were measured using various inlet-gas pressures (1.0 bar–30.0 bars) and compared to those obtained by the traditional axial-direction method. The results show that the concrete gas permeability in radial-direction reaches stable permeability zone (SPZ) with inlet-gas pressure exceeding 6.0 bars, which is faster than the SPZ with inlet-gas pressure exceeding 15.0 bars of the axial-direction gas permeability obtained by the traditional method. Under the same inlet-gas pressures of 6.0 bars–10.0 bars, the intrinsic permeability values in the radial and axial directions are near to each other with the standard deviations of 2.83%~9.90% while the apparent permeability values in the radial direction are lower than those in the axial direction by reductions of 3.69%~21.89%. The evolution of apparent gas permeability in radial-direction obeys well the typical model with the low coefficients of variation from 1.01% to 12.55%, indicating that the as-obtained apparatus combined with the proposed theoretical-model can quantitatively and accurately evaluate the radial-direction gas permeability of cement-based materials.

开发了一种以提出的理论模型为指导的创新设备，用于评估稳态流下水泥基材料的径向气体渗透率。测试条件是在环形混凝土腔中有较高的进气压力，以监测压力随时间的下降情况。带有嵌入式柔性传感器的巧妙的有机硅橡胶垫圈有效地提高了空腔的气密性，并在数量上进行了表征。不同水-水泥比（w / c）的环形混凝土的径向气体渗透率）使用各种进气压力（1.0 bar–30.0 bar）测量了0.35-0.55的比率，并将其与传统轴向方法获得的比率进行了比较。结果表明，当进口气体压力超过6.0 bar时，混凝土的径向气体渗透率达到稳定的渗透率区（SPZ），比获得的轴向气体渗透率超过15.0 bar的SPZ快。用传统方法。在相同的进气压力（6.0 bar-10.0 bar）下，径向和轴向的固有渗透率值彼此接近，标准偏差为2.83％〜9.90％，而径向的表观渗透率值较低比轴向减少3.69％〜21.89％。