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Utility tunnels are crucial infrastructure projects for cities. Earthquakes are a leading cause of damage to these tunnels. The effect of a non-homogeneous site, as a complex site, on the seismic response of utility tunnels cannot be ignored. Therefore, in this study, a non-homogeneous three-dimensional finite element model of a utility tunnel was created using the ABAQUS 2021 software. El Centro seismic waves were inputted while changing the structural depth of burial to investigate the utility tunnel's seismic response. This research is expected to further clarify the seismic variation in the utility tunnel under complex site conditions. The results show the following: (1) The impact of structure burial depth on the utility tunnel in a non-homogeneous site should not be neglected. The peak acceleration shows a decreasing and then increasing trend with increasing depth of burial within 10 m. Under the same site conditions, the peak accelerations and amplification factors of the soil in the clay are larger than those in the sand. (2) In identical site conditions, the utility tunnel structure experiences larger peak displacements in clay compared to sand. As the structure is buried deeper, the peak displacement of the utility tunnel gradually decreases, while the rate of decrease in the peak displacement of the utility tunnel structure gradually increases. The rate of decrease in peak displacement in clay is greater than that in sand. (3) The stress distribution of the utility tunnel structure changes as the depth of the structure increases. In the clay area, the utility tunnel structure shifts from transverse bending deformation to vertical bending deformation. In the sand area, it maintains transverse bending deformation due to the non-homogeneous site. The findings from this study offer guidance for building utility tunnels on non-homogeneous sites. [ABSTRACT FROM AUTHOR]

Jiangxi red soil was used as the tested soil and water spinach (Ipomoea aquatic) and Chinese chive (Allium tuberosum) were used as the tested vegetables in this study to investigate the effects of different amounts of sewage-sludge application on the growth of vegetables and the migration and enrichment patterns of Cu and Zn in vegetables using the potted method. The results indicated that the application of sewage sludge could improve the properties of red soil and promote vegetable growth. The dry weight of water spinach and Chinese chive reached the maximal levels when treated with the amount of sewage sludge at 4% and 10%, which was 4.38 ± 0.82 g and 1.56 ± 0.31 g, respectively. The dry weights after the application of sewage sludge were all larger than control treatment (CK) without sludge application. With increases in the applied amount of sewage sludge, the concentrations of Cu and Zu in red soil continued to increase, and the peak value was not reached. After the two vegetables were planted, the concentrations of Cu and Zn in red soil decreased by different degrees. The degrees of decrease of Zn were generally higher than those of Cu. The enrichment coefficient of water spinach on Cu showed a trend of increase followed by a decrease and reached the peak value of 1.04 ± 0.38 when the applied amount was 4%. The enrichment coefficient of Chinese chive on Cu overall showed a decreasing trend and did not reach the peak value under the treatment levels used in this experiment. The enrichment pattern of Chinese chive on Zn was not obvious, and the differences among all treatment levels were not significant (p