Three‐dimensional laser scanning technology can comprehensively and accurately monitor slope deformation. To conduct deformation monitoring and stability evaluation of the Changzhou Shunguoshan landslide, in this paper, the causes of the Changzhou Shunguoshan landslide were analyzed. Consequently, 3D laser scanning technology and the traditional monitoring methods such as data from the total station were compared. The point cloud data provides big data support for landslide deformation monitoring and landslide stability early warning. Meanwhile, the landslide stability was evaluated by analogy with existing studies on slope deformation monitoring data. Results show that the three‐dimensional laser scanning monitoring data is similar to the total station monitoring data. The overall deformation of the Shunguoshan landslide is no more than ± 0.0015 m; the deformation of the Liyang slope is less than ±0.09 m, which is far less than the analog slope deformation monitoring data. The slope construction and monitoring process are in a stable state.

Globalization is bringing increased industrialization and municipal solid waste (MSW). This is a major concern in heavily populated areas. In order to reduce MSW generation, incineration is commonly used, resulting in two types of ashes: bottom and fly ash. Bottom ash is gathered at the incineration bed and is larger in mass than fly ash. To test the qualities of high-performance mortar, MSW-BA in three sizes (fine, medium, and coarse) was replaced with sand at three replacement levels of 10%, 20%, and 30%. The high-performance mortar integrating MSW-BA was tested for hardened density, mechanical properties such as compressive and flexural strength, resistance to NaOH solution, and heavy metal leaching. The substitution level of MSW-BA increased the hardened density of the mortar mixes. The volume change and residual strength of the mortar mixes were measured following exposure to the NaOH solution. Fine-particle mortar mixes shrank whereas medium- and coarse-particle mortar mixes expanded. The largest loss in flexural and compressive strength was recorded when 20% of sand was replaced with a fine fraction of MSW-BA. Heavy metals including cadmium and copper were not leached from MSW-BA combinations of any size. The minuscule amounts of lead and zinc discovered were well below acceptable limits. The present study illustrates the MSW-BA can be utilized as a substitute for sand in the development of high-performance mortar.

The construction of group foundation pits near subway stations often leads to environmental pollution, thereby causing certain damage to urban ecology. By optimizing the excavation sequence of group foundation pits, the adverse effects on surrounding underground structures and soil during excavation can be effectively mitigated, contributing to the sustainable development of cities. Taking a group foundation pit project in Changzhou as an example, this study utilized the finite element software PLAXIS 3D to simulate various working conditions under different excavation sequences, comparing the deformation of the subway station, shield tunnel, and surrounding soil. The results show that, influenced by the excavation of group foundation pits, the difference between maximum deformation and minimum deformation of shield tunnel is 25.85%, and the difference between the maximum deformation and minimum deformation of the subway envelope is 19.44%. The subway envelope is least affected by the change in excavation sequence. Both the displacement of the subway station and the surrounding soil exhibit a significant “cumulative effect”, with displacement changes closely related to the distance from the pit to the station and the ground, as well as the amount of soil unloaded in each excavation. Therefore, it is advisable to adhere to the principle of “far before near, shallow before deep, small before large” during excavation, which facilitates the coordinated development of urban infrastructure construction and the urban ecological environment, providing valuable reference and guidance for the sustainable development of cities.

To investigate the deformation effects of different excavation sequences on subway stations adjacent to complex group foundation pit projects, this study, leveraging an actual project in Changzhou, conducted numerical simulations using the finite element software PLAXIS 3D. By comparing the deformation results of six different excavation sequences, a systematic analysis of their impacts on subway stations was conducted. Results reveal a noticeable “cumulative effect” in the deformation of subway stations and shield tunnels due to the excavation of group foundation pits, with deformation increasing gradually as subpits are excavated. Displacement variations are closely associated with the distance and volume of soil unloading. Notably, within a certain range, altering the excavation sequence of adjacent pits has negligible effects on deformation. Thus, adhering to the excavation principle of “far before near, shallow before deep, small before large,” rational excavation sequencing can effectively mitigate adverse impacts of group foundation pit projects on adjacent subway stations, thereby, bearing crucial significance for the safe operation of subway stations.