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In recent years, ecological building of bridges has gradually begun to appear in cities, and this trend is conducive to the sustainable development of urban bridges and an ecological environment, promoting the development of emerging industries around cities and driving the development of the urban economy. Bridges’ ecological aesthetic design cannot be separated from ecological aesthetics, and the relationship between these two factors is complementary and inseparable. This paper focuses on the relationship between the teaching of a bridge aesthetic design course and ecological landscape sustainable development. Based on a visual impression hierarchy deep learning model and a statistical analysis of a questionnaire, including reliability and validity analyses, a teaching model for the design of landscape bridge structure systems was constructed. Landscape bridge structure systems combine the dimensions of function, form, mechanics, and culture, and the teaching design model of landscape bridges must include non-professional students, undergraduate students, graduate students, and graduates working in enterprises. Investigations were performed of the urban block landscape, water environment landscape, urban garden landscape, and landscape bridges within natural mountain landscapes. The results showed that: (1) the influence and role of landscape aesthetics related to the water environment and urban garden landscapes are the most important; (2) in the teaching of a bridge aesthetics course, sustainable ecological development must consider the aesthetic value of landscape bridges while ensuring function and safety; and (3) for students at different learning stages, the focus in terms of bridge aesthetic system elements is different. Both the bridge structural landscape configuration and the ecological aesthetics must be considered together during the teaching of bridge aesthetics design courses. To achieve such a goal, students at different levels must have a good understanding of ecologically sustainable development and bridge aesthetics.

To promote the effective utilization of sludge and slag produced in nature and from human activities, this paper summarizes the research progress in the field of building materials on the basis of expounding their classification and characteristics. (1) Sludge and slag include silt, sludge and industrial waste residues. These three materials are mainly composed of SiO2, which can be used to produce building materials after treatment and can also be used as admixtures, including roadbed admixtures. (2) Silt and sludge are widely used in building wall materials and roadbed materials, etc. Industrial waste residues can be used in the production and processing of green concrete and glass-ceramics. (3) In addition to continuing to use existing utilization methods, key treatment technologies and new treatment devices can be further developed according to the characteristics of sludge and slag. Moreover, observations and mechanistic analysis of the microscopic structure of industrial waste residues and research on strong and weak utilization methods based on the performance of building materials can be carried out, and more efficient and energy-saving excitation or activation technologies will be developed. These efforts will eventually lead to the development of functional building materials with excellent performance and environmentally friendly characteristics to achieve the differentiated utilization of silt, sludge, and industrial waste residues and realize the efficient transformation of resources. This paper provides useful insights for the application of sludge and slag in the field of building materials.

With the day–night temperature and moisture levels changing every day, expansion and shrinkage of concrete slabs is always occurring; therefore, joints provide extra room for concrete slab deformation. The joint spacing in jointed plain concrete pavement (JPCP) is continuously affecting long-term pavement behaviors. In this study, data from the Long-Term Pavement Performance (LTPP) program were analyzed, and the behaviors of JPCP with different joint spacings were compared to discover the joint spacing effects. Since LTPP has an enormous database, three representative sections located in different states were selected for analysis, where the variable factors such as temperature, moisture, and average annual daily truck traffic (AADTT) were almost the same between the three sections. Three different joint spacings, including 15 ft (4.5 m), 20 ft (6 m), and 25 ft (7.5 m), were compared based on the collected LTPP data. The involved long-term pavement performances, such as average transverse cracking (count), average JPCP faulting, international roughness index (IRI), and falling weight deflectometer (FWD) deflections were compared between JPCP with different joint spacings. Based on the comparative analysis, the JPCP constructed with a 15 ft joint spacing demonstrated the best long-term performance. It showed no transverse cracking, the lowest average JPCP faulting, the best IRI value, and the smallest FWD deflection during the entire in-service period. With proper joint spacing, the cost of road maintenance throughout the life cycle could be significantly reduced due to there being less distress. Therefore, it is recommended to optimize the joint spacing to about 15 ft in JPCP in future applications.