Severe Cold Area Research Articles

Feasibility investigation on a novel data center cooling system based on cross-seasonal soil cool storage in severe cold area

In response to excessive energy consumption and high carbon emissions associated with the current data center cooling system, the advancement in the utilization of instant free cooling has progressively halted. A novel data center cooling system based on cross-seasonal soil cold storage is proposed，which makes full use of the cold stored in the soil across the seasons and air cold source for realizing the year-round free cooling. A dynamical simulation platform, which describes its operation characteristic, is established to analyze the feasibility. Results indicate that in the typical severe cold area of Harbin, the soil cooling during summer is sufficient to meet the cooling requirements of the data center. The maximum outlet temperature of the ground heat exchanger is only 8.9 °C when releasing cold. The cold energy stored across seasons in the soil can be effectively utilized, achieving a utilization rate of 98.04 %. In Harbin, Changchun, and Shenyang, the cooling capacity stored across seasons accounts for 31.4 %, 32.2 %, and 36.9 % of the total annual cooling capacity of the system, respectively. The annual average coefficient of performance for the system is 13.63, 12.52, and 10.44, respectively. Compared to the cooling system that does not utilize cross-seasonal soil cool storage but achieves efficient use of instant natural cold sources, these values represent an increase of 4.92, 4.02 and 2.62, respectively. Overall, this system demonstrates excellent applicability in severe cold area.

Indoor Radon Concentrations in Severe Cold Area and Cold Area and Impact of Energy-saving Design on Indoor Radon in China.

This study investigated indoor radon concentrations in modern residential buildings in the Cold Area and Severe Cold Area in China. A total of 19 cities covering 16 provinces were selected with 1,610 dwellings measured for indoor radon concentration. The arithmetic mean and geometric mean of indoor radon concentration were 68 Bq m-3 and 57 Bq m-3, respectively. It was found that indoor radon concentrations were much higher in the Severe Cold Area than those in the Cold Area. The indoor radon concentrations showed an increasing trend for newly constructed buildings. It was estimated that the average effective dose from inhalation of indoor radon is 2.15 mSv and 1.60 mSv for the Severe Cold Area and Cold Area, respectively. The more and more rigid energy-saving design for residential buildings in the Severe Cold Area and Cold Area has an obvious impact on the increased trend of indoor radon due to extremely low air exchange rate in China.

Impact of operation strategies on performance of integrated kang-floor heating system in severe cold areas

Efficiently and cost-effectively meeting the heating requirements of residents in severely cold regions by utilizing solar energy is currently a pressing need. Therefore, a solar heating system that integrated Kang-floor heating was established and tested for a passive solar house in Gan-nan Tibetan. This study reveals the effects of adjusting the flow/intermittent time periods and implementing variable flow rate operations on performance of system, to improve energy efficiency and optimize sleeping comfort. Findings indicated decreasing flow/intermittent time to 15/15 min had strengthened the average heat transfer from the water side, and mitigated the influence of returning water on internal water temperature of the tank, ultimately enhancing heat supply. The heating period was divided into three stage (18–24, 0–4, 4–8 o'clock), with a specific flow rate assigned to each stage. Under five flow rate configurations(A-E) with identical initial conditions: during constant flow rate, the greater the initial supply water temperature of the system, the more heat was transferred to room, and the higher heating efficiency was achieved, however, under variable flow rate, the effect of the water temperature on heating efficiency was significantly less evident. Mode B (low-to-high flow rate) had the highest heating efficiency and heat supply. The heating rate and cooling rate of Kang surface, temperature variations were notably less compared to the other four modes. Shortening the flow/intermittent periods and implementing variable flow method could improve the system's heat supply and sleep comfort with limited capital and resource investment.

Multi-objective hierarchical strategy for university dorm renovation in severe cold areas

In China, there are many old buildings whose renovation could enhance building environment quality, reduce energy consumption, lower carbon emissions, and create economic benefits. However, there is currently a lack of efficient architectural renovation optimization methods to provide decision-makers and designers with highly feasible renovation plans. This paper proposes an innovative optimization method for renovating old buildings to address this issue. The research employs a hierarchical optimization framework integrating Artificial Neural Networks (ANN), the NSGA-II algorithm, and the entropy-weighted TOPSIS method. The first layer's three-objective optimization using the trained neural network model significantly improves the algorithm's efficiency in searching for optimal solutions. The second layer's entropy-weighted TOPSIS optimization includes eight objective optimizations, such as energy, economy, and lighting, thus broadening the assessment dimensions. Taking an old multi-story university dormitory in the Shenyang area as an example, the study optimizes nine passive design variables across eight objectives. The hierarchical optimization results show that the high-scoring renovation plans can save 1.52 to 3.17 million yuan in energy costs over the building's remaining lifecycle and reduce carbon dioxide emissions by 644–962 kg per square meter. SRRC results indicate that external windows significantly impact economic efficiency and energy consumption, emphasizing the importance of selecting the right type of windows in actual engineering projects. The new method proposed in this study can offers a comprehensive and highly feasible renovation plan for old buildings.

Temperature Distribution Characteristics and Action Pattern of Concrete Box Girder under Low-Temperature and Cold Wave Conditions

In regions with severe cold and high latitudes, concrete structures are susceptible to cracking and displacement due to uneven temperature stress, which directly impacts their normal utilization. Therefore, to investigate the temperature distribution characteristics of concrete box girders under the combined influence of low temperatures and cold waves, a temperature test was conducted on a model of concrete box girders in Xinjiang Province, China. Based on the measured data, the distribution pattern of the most unfavorable negative temperature differential observed in high-latitude regions was determined. Long-term numerical simulation and extreme value analysis were performed using historical meteorological data, revealing that the vertical negative temperature gradient in the concrete box girder structures follows a composite exponential distribution. The temperature differential at the top complies with Chinese code requirements, while at the bottom, it aligns more closely with British standard BS5400. Statistical analysis of historical meteorological data predicts that the 50-year temperature differential will result in a drop amplitude of 26.42 °C, which is 1.44 times higher than measured values obtained from experiments. The proposed negative temperature gradient pattern for concrete box girders presented in this study can encompass general design codes and provide guidance for designing concrete bridges in severe cold areas.

Preliminary Research on Outdoor Thermal Comfort Evaluation in Severe Cold Regions by Machine Learning

The thermal comfort evaluation of the urban environment arouses widespread concern among scholars, and research in this field is mostly based on thermal comfort evaluation indexes such as PMV, PET, SET, UTCI, etc. These thermal comfort index evaluation models are complex in the calculation process and poor in operability, which makes it difficult for people who lack a relevant knowledge background to understand, calculate, and apply them. The purpose of this study is to provide a simple, efficient, and easy-to-operate outdoor thermal comfort evaluation model for severe cold areas in China using a machine learning method. In this study, the physical environment parameters are obtained by field measurement, and individual information is obtained by a field questionnaire survey. The applicability of four machine learning models in outdoor thermal comfort evaluation is studied. A total of 320 questionnaires are collected. The results show that the correlation coefficients between predicted values and voting values of the extreme gradient lifting model, gradient lifting model, random forest model, and neural network model are 0.9313, 0.7148, 0.9115, and 0.5325, respectively. Further analysis of the extreme gradient model with the highest correlation coefficient shows that individual factors (such as residence time, distance between hometown and residence, clothing, age, height, and weight) and environmental factors (such as air humidity (RH), wind speed (v), air temperature (Ta), and black bulb temperature (Tg)) have different influences on thermal comfort evaluation. In summary, using a machine learning method to evaluate outdoor thermal comfort is simpler, more direct, and more efficient, and it can make up for the lack of consideration of complex individual factors in the evaluation method of thermal comfort index. The results have reference value and application value for the research of outdoor thermal comfort evaluation in severe cold areas of China.

Characteristics Analysis of CO2 Concentrations and Temperature in Residential Buildings in Severe Cold Area Based on Field Measurement

This paper provides references for the design and control of high-quality green building indoor environments during the transitional season in severe cold area. A residential building in severe cold area was selected as the research subject, where indoor pollutant CO2 concentrations and temperatures were measured at the beginning of the transitional season. The study explored the variations in indoor pollutant temperatures and CO2 concentrations under natural and non-natural ventilation conditions, in conjunction with an analysis of the occupants' activities. The results demonstrated clear relationships between indoor pollutant CO2 concentrations and temperatures under natural ventilation conditions. Based on these findings, recommendations for natural ventilation strategies that consider both indoor CO2 levels and thermal environment are proposed.

Research on ultra-low energy consumption renovation of teaching buildings in severe cold areas under EPC mode

In order to explore the energy saving benefits and economy of ultra-low energy consumption renovation of existing buildings in cold areas under the contract energy management (EPC) mode under different renovation schemes. On the basis of the existing net present value and net present value increment, the net present value rate is proposed as the evaluation index of the transformation plan, so as to realize the comprehensive benefit evaluation of a variety of transformation schemes. The results show that the energy-saving transformation scheme of the project with an external wall of 120 mm rock wool board, a 150 mm extruded polyphenylene board on the roof, and a three-glass single Low-E argon-filled glass on the exterior window has the greatest comprehensive benefits and meets the ultra-low energy consumption standard, the energy saving rate of the envelope transformation reaches 28.07%, and the static recovery period is 5.27 years. This paper provides a design method and reference basis for the ultra-low energy transformation of existing buildings in cold areas using EPC mode.

Numerical study on the effect of optimizing the Trombe wall structure with built-in fins on improving building energy efficiency in severe cold region

In order to save heating energy and reduce carbon emission intensity, a floor heating room with built-in finned Trombe wall in Xining, Qinghai, a severe cold area, was taken as the research object. And ANSYS 2021 R1 was used to numerically investigate the effects of several major factors, such as fin height, fin transverse distance, fin longitudinal distance, fin inclined angle, fin shape, perforated shape and perforation ratio of perforated fin, on the average heat transfer coefficient (h) between the absorptive surface and the air in the interlayer. The results show that for fins with low heights, the enhancement effect of horizontal fins on the convective heat transfer of the absorptive surface of Trombe wall is greater than that of vertical fins. The enhancement effect of vertical fins on the convective heat transfer of the absorptive surface is more affected by fin transverse distance, while the enhancement effect of horizontal fins on the convective heat transfer of the absorptive surface is more affected by fin longitudinal distance. Besides, h shows a trend of first increasing and then decreasing with the increase of fin inclined angle, and reaches its maximum value of 5.89 W/(m2·K) at 45°. The fins with different shapes are equilateral triangular fins, semicircular fins, isosceles triangular fins and rectangular fins in descending order of their enhancement effect on the heat transfer of wall. Compared with solid fins, fins with circular holes can obtain a better convective heat transfer effect only when the open area ratio is 1:6. While fins with equilateral triangular holes can obtain better convective heat transfer effect as long as the open area ratio is greater than 1:7. Fins with elliptical holes do not significantly improve the heat transfer effect. On the basis of optimizing the fin layout and structure, the thermal performance of the improved Trombe wall during the 8:00∼16:00 period and its impact on indoor thermal comfort of the building were studied, and the energy-saving performance of the plan was discussed. Compared with the Trombe wall room with no fins, the improved Trombe wall can improve the heat teransfer efficiency and the building energy saving rate by 68.50 % and 53.57 %, respectively. The improved Trombe wall can only ensure the indoor thermal comfort in limited several hours, in the rest of time, the residents should add clothing to keep warm. These conclusions have an important effect of engineering guidance and great realistic meanings for promoting the process of solar building integration and achieving the “carbon peak and carbon neutrality” target.

Silver reversible electrodeposition device under −40 °C condition

Silver reversible electrodeposition devices (SREDs) find wide applications in intelligent windows, automobiles, intelligent displays, and other fields. They can achieve a mirror state close to 100% reflectance and generate plasmon phenomena of different colors by controlling the driving voltage. However, the switchability of these devices is compromised below 0 °C due to the molecular properties of the solvent dimethyl sulfoxide (DMSO), making it impossible to work in severe cold areas. This work has discovered a solvent called N-methylpyrrolidone (NMP), which possesses weak intermolecular forces, low dipolarity, and high solubility. By developing a SRED using NMP as the solvent, we have achieved a lower opening voltage at room temperature compared to the DMSO system. This is advantageous for the preparation of large-area devices. Additionally, the NMP system device retains its switching ability even under extreme conditions of −40 °C, freezing only when temperatures reach −43 °C, which is currently the lowest reported SRED operating temperature. This breakthrough brings us closer to the practicality of SRED.

Problems of Building Energy Consumption in Rural Schools in Linzhi, Tibet

The energy-saving research of school buildings in villages and towns in the severe cold areas of Linzhi Township has not yet been widely carried out. The energy consumption of schools in villages and towns in the severe cold areas of Linzhi is generally high, and the heating energy consumption in winter accounts for a large proportion of the energy consumption of school buildings. With the promulgation and implementation of energy-saving design standards for public buildings in schools in large and medium-sized cities, energy-saving activities have been carried out. In the severe cold area of Linzhi, there are a large number of buildings in villages and towns, with primary schools in each village, secondary schools and central primary schools in each township. The total energy consumption of village and town school buildings accounts for the majority of the total energy consumption of village and town public buildings. From this, it can be seen that studying the characteristics of village and town school buildings in the severe cold area of Linzhi and researching energy-saving design strategies suitable for their own characteristics based on the characteristics of village and town school buildings in the severe cold area are of great significance for the promotion and application of clean energy in schools in the Linzhi area.

Discussion on the Effectiveness of JGJ 26-2018 "Energy Efficiency Design Standard for Residential Buildings in Severe Cold and Cold Areas"

Building energy consumption is a substantial part of total energy consumption and is rising in the context of energy crises and environmental issues. To maximize energy savings and limit carbon emissions, the government recommends updating construction requirements. The Ministry of Housing and Urban-Rural Development of China proposed JGJ 26-2018 "Energy Saving Design Standard for Residential Structures in Extreme Cold and Cold Regions" in accordance to national policy. Several reports noted that some Chinese design requirements just stack energy-saving materials and technology without actually reducing energy consumption. This study proves the JGJ 26-2018's legitimacy. This essay first selects three major variables that have the largest impact on the energy consumption of buildings in extreme cold and cold areasexterior walls, roofs, doors, and windowsand then gathers four cases of housing restoration of these three essential components according to JGJ 26-2018. The partial success of the strategy is proven by comparing energy consumption before and after building renovations, which provides a reference for energy-saving residential building design in severe cold and cold regions.

Characteristics Analysis of Volatile Organic Compounds Pollution in Residential Buildings in Northeast China Based on Field Measurement

A total of 8 mechanically ventilated residential buildings and 8 naturally ventilated residential buildings were selected to analyze the pollution characteristics of indoor VOCs under different ventilation modes in the severe cold area of northeast China. On typical meteorological days in each season, VOCs were detected on site, and ventilation modes were investigated by long-term online monitoring. The test results showed that the TVOC (total volatile organic compounds) concentrations varied greatly in different seasons or different functional rooms, and the TVOC concentration was the highest in winter, with a value of 0.994 mg/m3. The kitchen was the place with the most serious VOC pollution, and the TVOC concentration could reach 1.403 mg/m3. Benzene series and methylsiloxane had the highest detection rates, but the detected concentrations were low, and the average concentrations were 0.025 mg/m3 and 0.013 mg/m3 respectively. Among the VOC types with a detection rate greater than 50%, the average proportions of aldehydes, alkanes, and benzene series were 18.7%, 15.39%, and 14.38%, respectively. And their mass ratios were also high, which were 14.90%, 30.85%, and 15.70%, respectively. The annual daily average ventilation duration of mechanically ventilated residential buildings was 7.84 h longer than that of naturally ventilated residential buildings. The median TVOC concentrations of mechanically ventilated residential buildings and naturally ventilated residential buildings were 0.621 mg/m3 and 0.707 mg/m3, respectively. The fresh air system was applicable in the severe cold area of northeast China.

Thermal adaptation of southern migrants to the district heating environment in the severe cold area, China: A longitudinally traced investigation

Preference for thermal environments is affected by the thermal histories on their own. A deeper understanding of human thermal adaptation to create comfortable and energy-saving environments is desired. To study the differences in thermal responses of southern migrants and northern locals to district heating environments, a longitudinally traced investigation was performed in the severe cold area, China. 74 freshmen with different thermal histories were invited for six weeks in winter. Physiological parameters and thermal response votes were collected. Results showed that the most significant difference in the thermal neutral temperature between locals and migrants reaches up to 1.1 °C, after acclimation, which decreases to 0.7 °C. Also, southern immigrants are not as sensitive to temperature changes as locals, but the gap is narrowing. Moreover, immigrants tended to wear lighter clothing at the same room temperature compared to natives, who were more flexible in adjusting their clothing. It was also observed that physiological and psychological adaptation processes were not synchronous. The humidity is the leading purpose of physiological discomfort for migrants. Physiological adaptation is a relatively slow process. It concluded that southern immigrants may take approximately 1 week to adapt to the thermal environment with district heating. However, they did not fully adapt to the humid environment until the 6th week. The findings have implications for understanding the mechanisms of thermal adaptation and creating comfortable built environments.

Energy-Saving and Ecological Renovation of Existing Urban Buildings in Severe Cold Areas: A Case Study

High-rise buildings in cold regions have a requirement of ecological improvement due to the continuous response to climate change throughout the year. This study evaluates wind environment, light environment, thermal environment, and energy consumption environment using Phoenics, Ecotect, and DesignBuilder tools, utilizing a high-rise residential building in an intensely cold place as an example. With the goal of repairing the buildings, green energy-saving measures are applied from the perspectives of form, structure, system, and equipment strategy. The energy-saving rates and carbon dioxide emission reduction rates of the renovated buildings were predicted. The results reveal that, in the building performance diagnostic, the wind speed clearly rise at the building’s corner, particularly on the outdoor level and the top floor; meanwhile, the inside lighting is insufficient, and there is a glare hazard adjacent to the window. The performance of the target building has unquestionably increased following the repair of 12 measures, including the bay windows, exterior walls, and solar energy. The influence of strong winds in winter and tranquil winds in summer greatly decreased in terms of the wind environment. In the light environment, indoor lighting is more uniform; the range of (Universal Design index) UDI100–2000 increased from 9.2% to 32.7%; and UDI2000, which may cause glare, decreased by 28.4%. Energy savings and pollution reduction rates were as high as 19.8% and 38.8%, respectively, due to the installation of solar photovoltaic panels. Based on all the measures, the overall energy saving rate of the target building was 63.8%, and the CO2 emission reduction rate was 90.3%.

Optimization of an integrated system including a photovoltaic/thermal system and a ground source heat pump system for building energy supply in cold areas

The photovoltaic (PV) collectors tend to overheat in summer, which reduces the efficiency of power generation. The unbalanced heating and cooling loads cause the ground source heat pump (GSHP) system to operate unstably in severe cold areas. To solve the above two problems simultaneously, an integrated system including a photovoltaic/thermal system and a ground source heat pump system (PVT-GSHP) was proposed, which had an extremely high energy utilization efficiency. However, the complex variation of cooling and heating loads was influenced by meteorological conditions over time. The demand of efficient operation and good economy of the system challenged the optimal configuration and control strategy among multiple energy sources, which was investigated in this study. A dynamic model of the PVT-GSHP system based on TRNSYS was developed and the corresponding control strategy was formulated. The genetic algorithm was used to optimize the matching of buried pipe lengths and PVT collector areas. The effects of different matching on the system parts and the whole performance were analyzed. The results show that increasing the PVT collector area can increase the ground temperature and shorten the buried pipe length, but it is not good for summer cooling, thus there is an optimal match. Compared with two independent systems of the traditional GSHP system and PV generation system, the PVT-GSHP system has excellent advantages and application prospects because it has 48.3% reduction in the total buried pipe length, 68.89% reduction in the footprint area of ground heat exchangers, 10% increase in the heating coefficient of performance (COP) and 72.3% reduction in life circle cost. This study provides theoretical support for the optimal design of the PVT-GSHP systems and similar complementary multi-energy systems.

School Energy Consumption and Children’s Obesity: Evidence from China

Rising obesity rates may lead to an increase in greenhouse gas emissions, undermining carbon neutrality goals. However, evidence of the determinants of obesity from the perspective of energy economics is relatively limited. We contribute to the literature on the determinants of obesity by empirically studying the relationship between the school energy consumption and children’s BMI. Based on a combined dataset of Chinese children’s physical health data, kindergarten energy consumption data, and kindergarten geographic information data, we find that school energy consumption is negatively correlated with obesity, and there is considerable heterogeneity in the relationship of school energy consumption between kindergartens in cold areas and severe cold areas and between young girls and young boys. Our results are robust to alternative modeling techniques, the inclusion of additional control variables, and unobservable potential effects. We also find that children’s exercise ability is an important transmission channel between school heating and the probability of obesity.

Preliminary monitoring and performance evaluation of photovoltaic system in rural buildings in severe cold area

ABSTRACT In recent years, the photovoltaic (PV) systems of rural buildings have been demonstratively applied in severe cold areas of China. However, the lack of power generation performance and economic evaluation results is not conducive to the PV promotion. This study innovatively presented the performance and economic evaluation of the grid-connected rural building applied PV (BAPV) system in Hailar, China from the predicted and measured data. The measured monthly PV outputs were counted and analyzed from the year 2020 to 2021. The ambient temperature, solar radiation and predicted output were obtained by the software of PVSYST. The performance ratio (PR), efficiency and loss were investigated, and their relationship with temperature and sunshine was analyzed. According to the measured data and theoretical calculation, the payback periods and profits were calculated. The results indicate that the measured output yields are 14,123.70 kWh in 2020 and 13,265.10 kWh in 2021, which are 6.05%~11.76% lower than the predicted value due to snow cover in the cold months. The monthly predicted array output is about 3.4% higher than the energy output. The array capture loss (L C ) is 14.99–34.80 kWh and the system loss (L S ) is 29.6–5.81 kWh. The PR is 83.30%-99.80%. The average system efficiency and array efficiency are 16.15% and 15.62%. The lower PR and efficiency are caused by the high temperature. The measured and theoretical payback periods are 6.7 and 5.6 years, respectively. The theoretical annual rate of income is 4828.15 Chinese yuan (CNY). These results provide an important reference for the promotion of rural residential BAPV in severe cold areas.

Optimization of double-layer shaped phase change wallboard in buildings in two typical climate areas in China

Phase change material (PCM) applied in buildings can significantly improve thermal comfort and realize building energy conservation. In recent years, double-layer shaped phase change wallboards (DLSPCWs) that depends on the latent heat absorption and release of two kinds of PCMs can effective control the indoor temperature fluctuation, and have been play an important role in improving the indoor thermal environment. The related researches show that, it is rare but necessary to optimize the DLSPCWs in different typical climate areas in order to further promote the application development of PCMs in buildings for energy conservation. Aimed this, fifty-four different DLSPCWs were constructed in this study by selecting different phase change thermal storage layer from four kinds of form-stable PCMs and changing the thickness of the layer to optimize the structure of DLSPCW in two typical climate areas, including severe cold area (Xining city, China) and hot summer and warm winter area (Haikou city, China) respectively. Comsol Multiphysics was used for heat transfer simulation and calculation of the DLSPCW in order to determine its best structure combination pattern for the two areas, and DesignBuilder for comparing and analyzing the building energy conservation effect when using the optimal DLSPCW in buildings. Compared with the ordinary wall, the optimized DLSPCW saved 14,198.96 kW·h electric energy during the heating period in Xining, while 18,816.62 kW·h electric energy in Haikou during the cooling period. The results proved that the optimum structure of the DLSPCW not only reduced the heating load and the cooling load but realized the maximum utilization of the PCMs.

Improvement on freeze-thaw durability of municipal solid waste incineration fly ash-based autoclaved wall blocks by triethoxy(octyl)silane/nano-Al2O3 and triethoxy(octyl)silane/graphene nanoplatelets coatings

The envelope structures hardly have the service life up to the design life in severe cold area. Polymer/nano-materials composite coatings are used to enhance the freeze-thaw durability of wall materials. Municipal solid waste incineration fly ash and fly ash were used to fabricate solid wastes-based autoclaved wall blocks (SW-AWBs) with hydrothermal synthesis method. Nano-Al2O3 and graphene nanoplatelets were modified by the coupling agent and used to prepare composite coatings with triethoxy(octyl)silane. Effect of different coatings on the durability of SW-AWBs was compared and discussed. The results showed that the specimens surface changed from hydrophilic to hydrophobic after treated by composite coatings. Meanwhile, the capillary absorption coefficient of SW-AWBs decreased by 57.3%–78.8% and 92.4%–94.1% after treated by triethoxy(octyl)silane/nano-Al2O3 and triethoxy(octyl)silane/graphene nanoplatelets coatings, respectively. Under 15 freeze-thaw cycles, the mass loss of SW-AWBs dropped by 61.9% and 69.4%, the strength loss reduced by 70.5% and 79.4% after treated by triethoxy(octyl)silane/nano-Al2O3 and triethoxy(octyl)silane/graphene nanoplatelets coatings, respectively. Overall, triethoxy(octyl)silane/graphene nanoplatelets had a superior effect on improving the freeze-thaw durability of SW-AWBs than triethoxy(octyl)silane/nano-Al2O3.