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The stability of shield tunnel segmental linings is highly sensitive to the lateral pressure coefficient, especially under weak, heterogeneous, and variable geological conditions. However, the mechanical behavior of steel plate-reinforced linings under such conditions remains insufficiently characterized. This study aims to investigate the effects of varying lateral pressures on the structural performance of reinforced tunnel linings. To achieve this, a custom-designed full-circumference loading and unloading self-balancing apparatus was developed for scaled-model testing of shield tunnels. The experimental methodology allowed for precise control of loading paths, enabling the simulation of realistic ground stress states and the assessment of internal force distribution, joint response, and load transfer mechanisms during the elastic stage of the structure. Results reveal that increased lateral pressure enhances the stiffness and bearing capacity of the reinforced lining. The presence and orientation of segment joints, as well as the bonding performance between epoxy resin and expansion bolts at the reinforcement interface, significantly influence stress redistribution in steel plate-reinforced zones. These findings not only deepen the understanding of tunnel behavior in complex geological environments but also offer practical guidance for optimizing reinforcement design and improving the durability and safety of shield tunnels.

The profile of the inrun is crucial in ski jumping. With the development of technology, a considerable number of geometric lines have been proposed from a mathematical perspective and applied to the inrun. The third power function is the latest standard design of the transition zone profile proposed by the International Ski Federation (FIS). Therefore, the transition zone profile (third power function) was studied. The research on athlete’s force states can help make the profile better meet the competition requirements. The dynamic differential equations of the athlete were first obtained by considering air resistance and skiing friction. Mathematica was used to solve the equations, and the skiing velocity of the athlete at each structural point was obtained. Meanwhile, the skiing velocity of the athlete at the arc and the third power function were compared with the force. The results show that, under the condition that the length and height of the inrun are the same, there is no difference in the athlete’s skiing velocity. By comparing the athlete-exerted forces under two types of profiles, it was found that the third power function will make the athlete-exerted forces slowly increase without instantaneously raising the point of the arc, which is conducive to the maintenance of the athlete’s movement. It was shown that the third power function has a great advantage in controlling the reaction force of the athlete. Therefore, the inrun with a third power function in the transition zone is more conducive to the athlete’s skiing, which further improves the level of competition and optimizes the original inrun system. It can provide theoretical support for the application of the geometric profile of the ski jumping inrun at the Beijing Winter Olympic Games.

The process of urbanization has spurred economic growth and social challenges, necessitating research on public spaces in urban renewal to optimize design, enhance functionality, promote sustainable urban development, and improve residents’ quality of life. However, existing studies lack in-depth discussions on development trends and research focal points. This study addresses the gap in existing literature, by conducting a bibliometric analysis using data from the Web of Science Core Collection database from 1 January 2000, to 1 April 2024. Using visualization tools such as VOSviewer and CiteSpace, the study examines publication trends, collaborative networks among countries, institutions, and authors, co-citation relationships among key journals and articles, and emerging research hotspots through keyword analysis. A total of 393 papers were analyzed, with China contributing the highest number (65), followed by the United States (51). Leading contributors include Zazzi Michele and Anguelovski Isabelle. The top three journals for publications are Sustainability, Cities, and Land. Key research trends highlight themes such as space syntax, nature-based solutions, and sustainable transportation. These findings have significant implications for urban planning and policy, suggesting that future urban development strategies should increasingly incorporate sustainable design practices and nature-based solutions to address both environmental and social challenges. By identifying global research trends and highlighting future challenges, this study provides a comprehensive overview that will help policymakers and practitioners in urban planning align their efforts with cutting-edge research and emerging best practices for more sustainable and resilient cities.

The process of urbanization has accelerated economic growth while also presenting social challenges. Urban renewal is crucial for achieving sustainable urban development, especially by preserving traditional villages as cultural heritage sites within cities. This study employs Python algorithm programming and visual analysis functions to conduct a bibliometric analysis of 408 research papers on the preservation of traditional village cultural heritage in urban renewal from 1999 to 2023 in the Web of Science core database. The objective is to examine the historical background, current status, and future trends in this area. The analysis explores cooperation networks, co-citation relationships, co-occurrence patterns, and emerging characteristics of research on traditional village cultural heritage protection in urban renewal. It focuses on various aspects, such as authors, institutions, countries, journals, documents, and keywords. The results indicate that the study of traditional village cultural heritage protection in urban renewal can be divided into three developmental stages. “Sustainable development”, “cultural heritage”, “historic urban landscapes”, and “rural revitalization” are the research hotspots and future trends in this field. The results of this study provide a comprehensive overview of the evolution of research hotspots in this field and can help researchers willing to work in this research area quickly understand the research frontiers and the general situation.

Although it has been shown that color can influence mental health and behavior, few studies have discussed the effects of cool and warm colors in classrooms on the perceived emotions of elementary school students. In this study, we investigated the emotional changes of elementary school students in Yinchuan City, Northwest China in classrooms with cool and warm color tones. By using the Positive and Negative Affect Scale for Children (PANAS-C), the emotions of 123 third- to sixth-grade students in classrooms with cool and warm color tones were measured. We found the following conclusions: (1) Overall, the emotional responses of the subjects in both the cool- and warm-colored classrooms showed a tendency for positive emotions to be higher than negative emotions. (2) There was no significant difference between the effects of cool and warm colors on the overall emotion of elementary school students, but there were significant differences in specific emotions; Compared to warm colors, cool colors had a more significant effect on increasing feelings of calm (β = −0.365, p = 0.041). Compared to cool colors, warm colors were more likely to cause participants to feel mad (β = 0.186, p = 0.099). (3) The effects of cool and warm colors on students’ emotions differed significantly by gender and grade level. Cool and warm color tones had a significantly greater positive impact on females. In contrast, cool and warm colors had a more pronounced effect on males’ negative emotions. In addition, we found that grade level was significantly negatively correlated with overall emotion (β = −0.696, p < 0.001), with lower grades perceiving emotion more positively than higher grades. These findings provide important insights into the spatial design of elementary school classrooms and provide valuable comparative data for studies in different regional and cultural contexts, further enriching the empirical support of color psychology theory.

Cement mortar is one of the most important components of semiflexible pavement materials; however, the effects of cement mortar formulation on the performance and the grouting rate are rarely studied. Therefore, the optimum formulation of high-performance cement mortar (HPCM) for different types and contents was studied, and the grouting effect of the cement mortar was studied by rutting tests. The results show that polycarboxylate superplasticizer, expansion admixture, and accelerating admixture have different influences on the workability, the strength, and the drying shrinkage of HPCM, and the working ability of HPCM is good by adding these three admixtures. The strength at 7 days is 1.3 to 4 times that of the existing specifications, and the shrinkage rate is less than 0.2. The HPCM has higher early strength, and the strength development is stable in the later period compared with the other research studies. The semiflexible material has better pavement performance when the grouting rate is greater than 90%.

The stress-absorption layer in cement concrete pavement delays the development of reflection cracks and is good at fatigue resistance. Laboratory investigations of the anti-crack performance of the high viscous asphalt sand stress-absorption layer (HVASAL) and rubber asphalt stress-absorption layer (RASAL) were carried out by force-controlled fatigue crack propagation tests, for which three types of overlay structures with three types of pre-crack (i.e., the middle crack, the side crack, and the 45° inclined crack) were designed. A probability model was established to describe the propagation of the fatigue cracks. The fatigue crack propagation, the fatigue life, the crack propagation rate, and the crack propagation mechanism of the three types of overlay structure were compared and analyzed. The results show that the stress-absorption layers have good anti-crack fatigue performance, and that the RASAL is better than the HVASAL. The crack propagation patterns of the three types of overlay structure were found. In the double logarithmic coordinate, the curves of the three types of cracks are straight lines with different intercepts and slopes. The probability model quantifies the relationship between the crack propagation rate and ∆K. The influences of the three types of crack on the fatigue properties of the asphalt overlays are different.

To improve the antifreeze-thaw performance of asphalt pavement in the seasonal freezing regions, the temperature and the time of freeze-thaw test were redesigned based on the climatic characteristics of the regions, and the splitting tensile strength tests were carried out to determine the low-temperature performance of the asphalt mixture under the influence of the gradation and the asphalt-aggregate ratio. A mathematical model was built to investigate the freeze-thaw damage law. According to the test results of splitting tensile strength of the asphalt mixture under freeze-thaw cycles, the probabilistic damage variable of the asphalt mixture was redefined and a physical probability model was built to analyse the freeze-thaw damage. Based on the freeze-thaw damage development process and the mechanism of the asphalt mixture, the effective measures to improve the antifreeze-thaw performance were provided and demonstrated through the correlations among the damage parameters (the shape parameter α, the scale factor λ, and the gradient factor ν) and the freeze-thaw resistance of the asphalt mixture. The test results showed that the splitting tensile strength decreased with the increase of the number of the freeze-thaw cycles. With the same gradation, the splitting freeze-thaw damage degree of the asphalt mixture with 5.8% asphalt-aggregate ratio is about 6% less than others after the 18th freeze-thaw cycle. The freeze-thaw resistance increases with the asphalt-aggregate ratio. With the same asphalt-aggregate ratio, the splitting freeze-thaw damage degree of S-grade mixtures is about 11.8% higher than that of Z-grade mixtures. S-grade mixtures have positive effects on the freeze-thaw resistance. The results suggest new measures for further investigation on the design and maintenance of the asphalt mixture in the seasonal freezing regions.

Laboratory investigations of relaxation damage properties of high viscosity asphalt sand (HVAS) by uniaxial compression tests and modified generalized Maxwell model (GMM) to simulate viscoelastic characteristics coupling damage were carried out. A series of uniaxial compression relaxation tests were performed on HVAS specimens at different temperatures, loading rates, and constant levels of input strain. The results of the tests show that the peak point of relaxation modulus is highly influenced by the loading rate in the first half of an L-shaped curve, while the relaxation modulus is almost constant in the second half of the curve. It is suggested that for the HVAS relaxation tests, the temperature should be no less than −15°C. The GMM is used to determine the viscoelastic responses, the Weibull distribution function is used to characterize the damage of the HVAS and its evolution, and the modified GMM is a coupling of the two models. In this paper, the modified GMM is implemented through a secondary development with the USDFLD subroutine to analyze the relaxation damage process and improve the linear viscoelastic model in ABAQUS. Results show that the numerical method of coupling damage provides a better approximation of the test curve over almost the whole range. The results also show that the USDFLD subroutine can effectively predict the relaxation damage process of HVAS and can provide a theoretical support for crack control of asphalt pavements.

The three-point bending fatigue tests were carried out in order to accurately predict the fatigue life of an asphalt mixture based on the plateau value (PV) of the dissipated strain energy ratio (DSER). The relations of the dissipated strain energy (DSE) to the stress-strength ratio, temperature and loading rate were studied, and the constructions of the mathematical models of DSE and DSER were completed based on the change laws of the DSE. The relation of the fatigue life to the PV was determined based on the analysis of damage evolution, based on which the fatigue equation was established and used to predict the fatigue life. The results show that the change laws of DSE and DSER can be well described by the proposed mathematical models. The PV is defined as the average value of the DSER in the second stage and the fatigue life decreases in power function with the increase of PV, based on which the fatigue equation of Nf = A(PV)B was established, and the established fatigue equation is very close to that is used in the MEPDG. The fatigue equation can well predict the fatigue life asphalt mixture.