Lutetian limestones have been widely used in historical monuments within the Paris Basin during the course of the medieval and modern periods. Among the physical properties that can be used to assess the evolution of the limestones in situ in the buildings and their present health, the complex effective permittivity in the 10–100 kHz frequency range is easy to measure and reflects the internal structure of the stone along with the dependence on the water content. To improve our knowledge about this property, a laboratory study on four samples collected in the relevant quarries has been undertaken using measurements in the 100 Hz–10 MHz frequency range. Except close to zero water content, the observed results exhibit a quasi-absence of variation of the real effective permittivity with the water content. The frequency variation fits fairly well with a model taking into account a Jonscher's decrease, a direct current conductivity, a high-frequency dielectric permittivity and losses, and a relaxation phenomenon. When fitted by a Cole–Cole model, the magnitude of the corresponding relative permittivity change always stays close to 30, but the time constant varies from 1.0 μs to 0.1 μs as the water content increases.

中文翻译：

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卢特田灰岩在 100 Hz 至 10 MHz 频率范围内的电学特性的实验室研究

在中世纪和现代时期，Lutetian 石灰岩已广泛用于巴黎盆地内的历史古迹。在可用于评估原位石灰岩演化的物理特性中在建筑物及其当前的健康状况中，10-100 kHz 频率范围内的复杂有效介电常数很容易测量，并反映了石头的内部结构以及对含水量的依赖。为了提高我们对这一特性的了解，我们对在相关采石场采集的四个样品进行了实验室研究，使用 100 Hz-10 MHz 频率范围内的测量值。除了接近于零的含水量，观察到的结果表明实际有效介电常数随含水量的变化几乎没有变化。频率变化与考虑到 Jonscher 减小、直流电导率、高频介电常数和损耗以及弛豫现象的模型非常吻合。当由 Cole-Cole 模型拟合时，