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Natural stone is a traditional building material used worldwide for millennia. Its mechanical properties are rather well known, but only a small quantity of data is available regarding its hygrothermal characteristics. However, these characteristics are essential for the design of energy efficient buildings. Stones are in fact associated with insulation materials, which strongly modify the hygrothermal behavior of building walls, thereby impacting their durability and thermal comfort. This study focused on the hygrothermal characterization of a dozen samples of limestone, offering an adequate representation of their use across France. Thermal conductivity and heat capacity, sorption and desorption isotherms, water vapor permeability, and moisture buffer value (MBV) all were determined and analyzed. These data can be used to model heat and mass transfers in building walls. Limestone features extensive physical properties that can vary from one place to another within the same quarry. A statistical classification of the mechanical properties of thousands of French limestones was carried out. This classification allows estimating the hygrothermal properties previously determined for other stones. [ABSTRACT FROM AUTHOR]

This document is a correction notice for an article on the characteristics of limestones for energy-efficient and sustainable building components. The authors have identified errors in the original publication and have provided corrected values for certain measurements. The document includes a table with the corrected values for properties such as density, porosity, and thermal conductivity. The purpose of this correction is to ensure the accuracy of the published information. [Extracted from the article]

An in situ estimation of the thermal properties of bio-sourced building wall insulation components is of critical importance in improving both the energy efficiency of buildings and the development of construction materials with a smaller environmental footprint. Depending on weather conditions, passive methods are not always feasible; they require time to conduct lengthy testing and may lead to significant uncertainties. This article presents an active method based on power dissipation via flat electrical resistance. The method can be implemented regardless of outdoor weather conditions and is suitable for walls with high overall thermal resistance for which the small average component of the through flow is difficult to estimate. Measurements are conducted of both wall input flows and temperatures. An inverse method, derived from a finite difference model of 1D transfers along with a multi-objective approach, enables the characteristics of a two-material assembly to be identified. A multi-objective method was chosen to solve the problems of high correlation between the thermal parameters of the model. However, the method requires the use of two temperature sensors integrated inside the wall. Following a laboratory validation phase on a PVC/plasterboard assembly, the method is implemented on an actual wall. A coating/hemp concrete assembly is also characterized as part of this work program. The thermal conductivity of the hemp concrete block was estimated at 0.12 W m−1 K−1 and is consistent with values found in the literature. [ABSTRACT FROM AUTHOR]

In a period of surging energy prices, resource depletion, and concerns over the use of nuclear power, energy savings are paramount and a major component of ongoing sustainable development. Geothermal energy is the energy stored in the form of heat beneath the surface of the Earth. Related to this, the thermal properties of soils are of great importance, particularly with regard to the modern trends of utilizing the subsurface for transmission of either heated fluids or high power currents. For example, in geothermal hydrology or geotechnical engineering applications, the thermal conductivity must be determined to assess the energy potential of the soil. The presence of water (groundwater, rainfall, natural moisture) improves both the thermal conductivity and thermal capacity fields. We present an original method-based on a thermal study and the use of non-integer order models-to determine the thermophysical parameters of different soils in near-surface layers, and link them to the water content variations of different soils. The results are compared with those obtained using a capacitive profile probe. [ABSTRACT FROM AUTHOR]