Energy pile is a green, constant-temperature utilization technology with dual functions of heat exchange and load bearing. Improving its heat transfer efficiency has always been one of the main directions of scholars' research. This study discussed the optimization of heat transfer buried pipe parameters, modification of pile materials, and improvement of working fluid performance within the pipes. Additionally, based on the research achievements of the research team in recent years regarding heat transfer enhancement in energy piles, a comprehensive heat transfer enhancement system is summarized, aiming to provide new ideas and methods for the study of heat transfer enhancement in energy piles. The optimization status of different buried pipe types and pipe parameters is also summarized. The heat transfer performance and mechanical properties of different modified concrete materials are studied. A comparison and analysis of the heat transfer performance and flow characteristics of different types of circulating mediums with nanofluids are conducted, providing new approaches to improve the heat transfer performance of circulating mediums. Finally, discussions and prospects were made on the external environmental conditions around the pile, thermal interference phenomena of pile groups, energy storage concrete, the long-term stability of nanofluids, benefit assessment, and ecological evaluation. These efforts aim to promote research on energy piles both domestically and internationally.

Ground level enhancements (GLEs), which occur when high energy solar protons reach Earth, are a considerable space weather hazard for aviation activities. Neutron monitor (NM) observations of these events are the key input to operational models of ionizing radiation at aviation altitudes. Similarly, the NM data is key to techniques for deriving anisotropic solar proton spectra during GLEs. A higher density of observations is desirable for both purposes. In this paper, a simple way of improving the density of observations for large events is presented: the compact neutron monitor (CNM). This monitor uses the same unleaded detectors as soil moisture sensing networks. Three years of data from the CNM located in Guildford, UK, is presented. The solar cycle variation in cosmic rays is observed, alongside 4 Forbush decreases of varying magnitude. No GLEs were observed during this time, due to a lack of any events of sufficient magnitude to be observed. A future CNM station near Lerwick, UK is briefly described in addition to the Guildford station. The implications of the observations to date are discussed in the context of GLE detection. The CNM is complementary to existing and emerging NM designs, and may be suitable for use as a reference point for the soil moisture monitoring networks. The suitability of the CNM to GLE detection can be extrapolated to the soil moisture networks in the case of large GLEs; in the event of one occurring, the data may provide unprecedented spatial resolution.

The current Indian Standard Seismic Code IS 1893: Part 1 (2016) for general buildings lacks detailed guidelines on modeling soil-structure interaction (SSI) in the estimation of seismic demand and earthquake-induced damage in reinforced concrete buildings. Therefore, this study aims to investigate the effects of SSI, with a focus on its nonlinear behavior, on the seismic demand of ductile reinforced concrete frames designed as per IS 1893: Part 1. The selected RC buildings are designed for second-highest seismic risk zone in India and represent short, medium, and long-period structures commonly found across Indian sub-continent. The influence of SSI is studied for soil type II and type III, as specified in the Indian Code, which corresponds to medium stiff and soft soil sites, respectively. Using a nonlinear Winkler-based model, numerical finite element models of linear and nonlinear SSI have been developed for isolated shallow foundations. This study utilizes the results of incremental dynamic analysis to evaluate the fragility parameters for code specified performance limit states. Further, the estimated fragility parameters are integrated with the regional hazard curve coefficients to quantify the annual exceedance probability of specified damage levels. The simulation results highlight the critical impact of nonlinear SSI on the earthquake resilience of IS code designed low- to high-rise reinforced concrete buildings. Notably, the percentage increase in estimated fragilities is higher for low-rise buildings than high-rise buildings when subjected to ground motions on soil sites. Additionally, the vulnerability to failure of these buildings elevates significantly when they are analyzed on soft soil sites compared to medium soil and bedrock sites. Therefore, it is recommended to account for the significance of nonlinear SSI while assessing the expected structural performance and fragility of IS 1893: Part 1 designed stiff low- to medium-rise reinforced concrete buildings, as this step can substantially enhance the resiliency of such buildings in the aftermath of a disastrous earthquake.

In the concurrent extraction of coal and gas, the quantitative assessment of evolving characteristics in mining-induced fracture networks and mining-enhanced permeability within coal seams serves as the cornerstone for effective gas extraction. However, representing mining-induced fracture networks from a three-dimensional (3D) sight and developing a comprehensive model to evaluate the anisotropic mining-enhanced permeability characteristics still pose significant challenges. In this investigation, a field experiment was undertaken to systematically monitor the evolution of borehole fractures in the coal mass ahead of the mining face at the Pingdingshan Coal Mining Group in China. Using the testing data of borehole fracture, the mining-induced fracture network at varying distances from the mining face was reconstructed through a statistical reconstruction method. Additionally, utilizing fractal theory, a model for the permeability enhancement rate (PER) induced by mining was established. This model was employed to quantitatively depict the anisotropic evolution patterns of PER as the mining face advanced. The research conclusions are as follows: (1) The progression of the mining-induced fracture network can be classified into the stage of rapid growth, the stage of stable growth, and the stage of weak impact; (2) The PER of mining-induced fracture network exhibited a typical progression that can be characterized with slow growth, rapid growth and significant decline; (3) The anisotropic mining-enhanced permeability of the reconstructed mining-induced fracture networks were significant. The peak PER in the vertical direction of the coal seam is 6.86 times and 4446.38 times greater than the direction perpendicular to the vertical thickness and the direction parallel to the advancement of the mining face, respectively. This investigatione provides a viable approach and methodology for quantitatively assessing the anisotropic PER of fracture networks induced during mining, in the concurrent exploitation of coal and gas. (c) 2025 Institute of Rock and Soil Mechanics, Chinese Academy of Sciences. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/ 4.0/).

In this study, a green and cost-effective cement system was developed with bagasse ash (BA incorporating limestone calcined clay cement (LC3) as ordinary Portland cement (OPC) replacement from black cotton soil (BCS) stabilisation perspective. Effect of BA incorporating 20 % - 60 % range of LC3 on standard consistency (SC), setting time (ST) and compressive strength properties was investigated and optimised through comparison studies with similar properties to BA incorporating 20 % - 60 % range of OPC. Optimum content of BA incorporating LC3 was added to BCS in different mix proportion range of 0-18 %. Effect of addition of different content of BA incorporating LC3 on performance of BCS specimens was examined in terms of compaction, free swell and durability properties. The results show that utilisation of BA incorporating LC3 maintains compressive strength and improves SC as well as ST of BA incorporating LC3 paste. Compared to BA incorporating OPC, BA incorporating 40 % of LC3 content at 0.50 water-cement (w/c) ratio obtained a good comprehensive strength equivalent cement performance. From the experimental results, it was found that addition of BA incorporating LC3 at optimal content significantly improved compaction, swell potential and durability properties of treated BCS. This study demonstrates technical feasibility of BA incorporating LC3 as a cement replacement. It verifies the reuse of by-products from agriculture for application as cementitious materials. The study further promotes the utilisation of BA incorporating LC3 for addressing climate change emergency and reducing high costs for routine BCS stabilisation practice.

To improve the reinforcement effect of MICP technology on fine-grained soil, and consider the fine particle size and activity characteristics of red mud, the experiment of red mud strengthening MICP solidified fine-grained soil was designed and carried out. Combined with mechanical test and microstructural analysis, the enhancing mechanism of red mud on microbial solidified fine-grained soil was comprehensively evaluated. The results show that: (1) Red mud can significantly improve the production of cement during microbial reinforcement of fine-grained soils; the optimal dosage of red mud is 20 %, which increases the strength by 34.6 % and the production of cement by 42.9 %, compared with conventional MICP. (2) After red mud was incorporated into the soil, the pore volume and pore diameter of the treated soil were significantly reduced, and the overall compactness was further improved. (3) The enhancement mechanism of microbial consolidation of fine-grained soils by red mud is mainly due to the presence of chemically active b-C2S and calcium oxide in red mud. These active calcium-based components undergo hydration and carbonation reactions under the action of microbial mineralization, generating calcium carbonate and hydrated calcium silicate, which improves the cement yield and enhances the intergranular bond strength, compactness and overall reinforcement effect of the treated soil. (c) 2025 Production and hosting by Elsevier B.V. on behalf of The Japanese Geotechnical Society. This is an open access article under the CC BY- NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Expansive soil poses significant challenges for engineering due to its susceptibility to swelling and shrinkage. This study aims to explore effective methods for improving its mechanical properties using single alkaline activators, single slag, and their combination. Laboratory experiments were conducted to evaluate the unconfined compressive strength (UCS) and analyze curing mechanisms through X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results demonstrate that all three treatments enhance soil strength, with the combination of alkali-activated slag being the most effective, followed by the single alkaline activator and single slag. Optimal dosages were determined as 15% for the activator and slag individually and 15% activator combined with 20% slag, yielding the densest structure and highest UCS. The activator's modulus of 1.5 was found to be optimal, and strength improved further with extended curing time. A microscopic analysis revealed that alkaline activation formed gel-like substances and dense needle-like structures, while slag generated CaCO3 and Ca(OH)2. The combination produces a synergistic effect, creating substantial amounts of C-S-H, C-A-S-H gel, and dense needle-like structures, which enhance soil compactness and strength by binding particles and filling voids. These findings provide insights into the curing mechanisms and offer practical solutions for improving expansive soil in engineering applications.

The widespread reliance on single-use plastics (SUPs) has fostered a global throwaway culture, especially in the food packaging industry, where convenience and low cost have driven their adoption, posing serious environmental threats, particularly to marine ecosystems and biodiversity. Edible and ecofriendly packaging made from millet, specifically sorghum (Sorghum bicolor (L.) Moench), is a promising solution to mitigate SUP consumption and promote sustainability. This study explores the development of edible sorghum bowls, enhanced through roasting and incorporating 3 g of hibiscus and rose flower powders. The standardized sorghum bowl was analyzed for nutritional value; optical, technological, functional, and mechanical properties; and shelf life, and the results were discussed. The bowls, 18.5 g of average weight, dimensions of 10.2 cm, and a thickness of 3 mm, were baked in a unique bowl-shaped mold at 80 degrees C for 7 min. Enhancing the bowls with flower powder improved their optical properties and nutrient content. The addition of flower powder also increased phytochemical levels, according to qualitative analysis, while roasting sorghum reduced tannin and phytic acid content. The IC50 values revealed that hibiscus (47.74 mg/mL) and rose (39.87 mg/mL) enrichment boosted antioxidant activity. Sensory evaluations favored roasted bowls across all attributes, while Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analyzer (TGA) analyses confirmed significant structural changes. The enhanced bowls exhibited greater hardness and hold hot or cold snacks for 90 min without compromising structural integrity. Additionally, these bowls demonstrated an extended shelf life, low microbial count (1 x 101CFU/g), reduced toxicity (3%-10% mortality in brine shrimp assays), and complete biodegradation within 15 days in wet soil. These findings indicate that sorghum-based edible bowls present a nutritious, viable, less toxic alternative to SUPs, appealing to a broad demographic, especially in the food and tourism sector, and contributing to environmental conservation by reducing plastic waste and suitable for wide consumption.

Snow, characterized as a unique granular and low-density material, exhibits intricate behavior influenced by the proximity to its melting point and its three-phase composition. This composition entails a structured ice skeleton surrounded by voids filled with air and spread with liquid water. Mechanically, snow experiences dynamic transformations, including bonding/degradation between its grains, significant inelastic deformations, and a distinct rate sensitivity. Given snow's varied structures and mechanical strengths in natural settings, a comprehensive constitutive model is necessary. Our study introduces a pioneering formulation grounded on the modified Cam-Clay model, extended to finite strains. This formulation is further enriched by an implicit gradient damage modeling, creating a synergistic blend that offers a detailed representation of snow behavior. The versatility of the framework is emphasized through the careful calibration of damage parameters. Such calibration allows the model to adeptly capture the effects of diverse strain rates, particularly at high magnitudes, highlighting its adaptability in replicating snow's unique mechanical responses across various conditions. Upon calibration against established experimental benchmarks, the model demonstrates a suitable alignment with observed behavior, underscoring its potential as a comprehensive tool for understanding and modeling snow behavior with precision and depth.

This study aims to enhance the suitability of expansive clayey soils for use as landfill liners by incorporating water treatment sludge ash (WTSA). Expansive soils, prone to swelling and desiccation cracking, compromise landfill liner integrity, increasing the risk of groundwater contamination. Local soils often do not meet the requirements for hydraulic conductivity and stability, prompting the use of additives like bentonite. However, bentonite-treated soils still face challenges in tropical regions due to moisture loss and cracking. This research investigates the effects of adding WTSA to bentonite-treated soils to mitigate swelling and shrinkage issues. Several geotechnical tests were conducted, including hydraulic conductivity, free swell percentage, swelling pressure, volumetric shrinkage, and desiccation cracking. Results show that WTSA significantly reduces hydraulic conductivity, free swell percentage, and swelling pressure, meeting the standard requirements for liners (hydraulic conductivity of at least 1x10-9 m/s and volumetric shrinkage of at least 4%). Moreover, WTSA addition reduces desiccation cracking to acceptable levels, demonstrating its potential as an effective reinforcement material. This study introduces an innovative approach to using WTSA, a waste product, as a sustainable alternative to conventional liner materials, reducing environmental impact and enhancing landfill liner performance.