This study investigates the effects of incorporating date palm wood powder (DPWP) on the thermal, physical, and mechanical properties of lightweight fired earth bricks made from clay and dune sand. DPWP was added in varying proportions (0 %, 5 %, 8 %, 10 %, 12 %, and 15 % by weight of the soil matrix) to evaluate its influence on brick performance, particularly in terms of thermal insulation. Experimental results revealed that adding DPWP significantly reduced the thermal conductivity of the bricks, achieving a maximum reduction of 56.41 %. However, the inclusion of DPWP negatively impacted the physical and mechanical properties of the samples. Among the tested bricks, those with 8 % and 10 % DPWP achieved a desirable balance, maintaining satisfactory mechanical strength within acceptable standards while achieving thermal conductivity values of 0.333 and 0.279 W/m & sdot;K, representing reductions of 37.29 % and 47.46 %, respectively. To further validate these findings, prototypes of the DPWP-enhanced fired bricks and commercial bricks were constructed and tested under real environmental conditions during both summer and winter seasons, over a continuous 12-h daily period. The DPWP-enhanced prototypes demonstrated superior thermal performance, with temperature differences reaching up to 3 degrees C compared to the commercial bricks. These findings highlight the potential of DPWP as a sustainable additive for improving the thermal insulation properties of fired earth bricks, thereby promoting eco-friendly and energy-efficient building materials for sustainable construction practices.

This study assesses the hygrothermal performance of the Photovoltaic External Thermal Insulation Composite System (PV ETICS), using a thick layer of mortar with Phase Change Material (PCM) granules as a passive heat sink. The experimental scenario involved the wall system exposure to real outdoor climate conditions during a 20-month long measurement period. Measured data were compared with results from the hygrothermal modelling. The findings reveal that with carefully designed diffusion channels the PV ETICS demonstrated no accumulation of moisture behind the vapour-tight PV panel. Long term hygrothermal modelling for PCM mortar moisture content with a previously calibrated model predicted stable moisture content around 0.03 m(3)/m(3), significantly lower than the moisture content during first 2 years. Relative humidity behind the PV panel falls into the hygroscopic range on the second spring after the construction. The annual maximum temperatures for PCM mortar during two summers were 69 degrees C, occurring in mid-August. Risk analysis was conducted with historic climate data to understand, whether higher PCM temperatures could be reached in the same climate for different years. Overall, the wall system showed no signs of extensive moisture damage during the testing period, but slight discolouring of the PCM mortar was recorded. This study contributes valuable insights into the practical viability of PV ETICS with PCM mortar, reaffirming its potential for application on larger scale on real building facades.

There is an increasing demand for sustainable construction materials to address the challenges posed by the environmental impact of the built environment (BE), which is driven by climate change, population growth, and urbanization. Conventional construction materials like cement contribute significantly to carbon emissions during production, transport, use, and disposal phases, and their poor thermal conductivity hinders efforts to maintain comfortable indoor environments. To address these challenges, there is an urgent need for innovative, locally sourced thermal insulation materials specifically designed for regions with extreme climates and high energy demands to maintain building comfort. This research explores synthesizing novel, environmentally friendly building materials using locally sourced date palm fiber waste and clay. The study also investigates the developed material's 3D printing (3DP) capabilities and optimizes its printing parameters with lab-scale prototypes. Additionally, thermo-mechanical characterization is conducted to assess its suitability for built environment applications. Different concentrations, from 1 to 5 wt% of date palm fiber to clay ratio (Dpf/C), were studied regarding microstructural, thermal, and mechanical properties, dimensional accuracy, and feasibility for 3DP of BE structures. Results demonstrated a significant reduction in thermal conductivity by 73%, achieving 0.244 W/mK, and an increase in compressive strength by 106%, reaching 10.9 MPa at 5 wt% Dpf/C. The promising thermomechanical properties of these composites and their suitability for 3DP support their use in real-world applications in the future's sustainable built environment. This scalable methodology can be adapted to regions with similar sustainable local and waste resources, advancing the circular economy.

This study focuses on investigating the thermal, physical, and mechanical attributes of a light-weight fired earth brick composed of clay and dune sand, stabilized with lime. The study explores the impact of incorporating alfa plant powder and glass powder, constituting 15% and 10% respectively, relative to the soil matrix weight. This addition aims to attain optimized thermal, physical, and mechanical characteristics. Employing the statistical software, Statgraphics, experimental designs were created and analyzed, allowing for optimizations. The outcomes demonstrated a notable reduction in thermal conductivity, up to 42.36% and 23.91%, with the inclusion of alfa plant powder and lime, respectively. However, this led to a decrement in physical and mechanical properties. Conversely, the introduction of glass powder led to a decrease of total water absorption rates by as much as 4.52%. Utilizing the statistical program, an optimal ratio of 10.26% alfa powder was suggested, resulting in a brick with a thermal conductivity of 0.384 W/ m.K, a compressive strength of 8.561 MPa, and a total water absorption rate of 26.922%. These findings underscore the potential of incorporating alfa plant powder to enhance fired earth bricks, particularly in terms of thermal insulation. Additionally, it presents a sustainable and eco-friendly material technology.

With increasing global warming, the skiing season is shortened to different degrees all over the world. As a crucial way to ensure the sustainable development of the ski industry, snow storage has been gradually studied and applied in Europe. Covering thermal insulation materials is a key engineering measure for the success of snow storage. This study used numerical methods rather than an experimental method to evaluate the thermal insulation performance of nine snow storage coverage schemes in Harbin, Beijing, and Altay, China. We investigated the thermal insulation performance of nine snow storage coverage schemes (three natural materials and six artificial ones) using a solar radiation method and an implicit finite difference method. Sensitivity analyses were conducted, and the cost performance of schemes 5-9 were analyzed. Based on the cost and thermal insulation performance, we used schemes 4 (geotextile, straw bale), 5 (geotextile, extruded polystyrene foam), and 7 (geotextile, polyurethane foam) to evaluate the snow storage effects in Harbin, Beijing, and Altay. Results showed that among schemes 1-9, scheme 7 has the best thermal insulation performance. If natural materials are used, then scheme 3 gives the best thermal insulation performance. Among schemes 5-9, scheme 5 is the most economical. The heat transfer in Beijing is higher than that in Harbin and Altay, while the latter two show similar heat transfers. The combination of meteorological conditions and coverage schemes influence the melting rate of snowpacks. The melting rate of snowpacks can be reduced with an optimized coverage scheme. The proposed methods can serve the selection of coverage schemes for snow storage.