In order to study effectiveness of soil radon mitigation systems in dwellings basements, it is necessary to develop robust numerical models that can estimate time-varying radon concentration in the basements. However, development of such models is a very challenging topic. Indeed, there are three difficult tasks that have to be solved: i°) to characterize soil and foundation materials hydraulic properties, and geometry, length, and position of cracks inside these materials, ii°) to solve discontinuity due to free gas flow in a basement volume embedded within a tortuous porous material, and iii°) to characterize the dwelling occupation mode by the inhabitants. The purpose of this work is twofold: first, to investigate the performance of a meshed-basement model (BM1), compared to classical mass balance models (BM2), in simulating measured fluctuations in time of point-radon concentration in the basement; and second, to study efficiency of soil depressurization systems (SDS) designs in reducing the higher radon concentrations in basements due to higher under-pressurizations.

Application of both models to an experimental dwelling showed that BM1 is more efficient than BM2 in that it can better simulate both measured radon concentration and radon-entry-rate. Numerical SDS-scenarios by using BM1 showed that the basement sub-slab depressurization (SSD) alone is a costly solution for radon mitigation. However, scenarios combining SSD with a sump pumping well (SPW) design in the soil adjacent to the wall, showed to be a good alternative because it involves less energy for soil air extraction.

为了研究住宅地下室中土壤ra减缓系统的有效性，有必要建立鲁棒的数值模型来估算地下室中ra的浓度。但是，开发这样的模型是一个非常具有挑战性的话题。实际上，必须解决三个困难的任务：i）表征土壤和基础材料的水力特性，以及这些材料内部裂缝的几何形状，长度和位置，ii°）解决由于自由气流导致的不连续性。地下室容积嵌入曲折的多孔材料中，和iii°）以表征居民的居住模式。这项工作的目的是双重的：首先，与传统的质量平衡模型（BM2）相比，研究网格基础模型（BM1）的性能，模拟地下室中点point浓度的时间波动；其次，研究土壤降压系统（SDS）设计在降低地下室中较高ra浓度引起的ra浓度方面的效率。

两种模型在实验性住宅中的应用表明，BM1比BM2更有效，因为它可以更好地模拟测得的ra浓度和ra进入率。通过使用BM1进行的SDS数值模拟表明，单独的地下室底板降压（SSD）是缓解ra的昂贵解决方案。但是，将SSD与邻近墙壁的土壤中的污水泵井（SPW）设计相结合的方案被证明是一个不错的选择，因为它消耗的土壤空气能量更少。