Corrugated steel-plate culverts, particularly in horizontal ellipse form, are commonly used in large-span projects. Despite the guidelines on plate radius ratios, the impact of these ratios on mechanical properties remains unexplored. This gap highlights the need for research to guide utility tunnel design because existing studies mainly focus on round culverts compressed into elliptical shapes. Therefore, this study conducted backfill, simulated vehicle live load, and ultimate-load tests on two horizontal-ellipse corrugated steel utility tunnel structures with different top-side plate ratios to examine their response characteristics under various load conditions. Moreover, they were compared with those of existing design methods to offer new insights for the design analysis of soil-steel structures. The results demonstrated that the ratio significantly influenced bending moment distribution, and the critical was concentrated beneath the loading pad for live loads. The ultimate capacity varied with the ratio, with the higher ratio specimen reaching approximately 92.5 % of the capacity of its counterpart. Both specimens failed via tri-plastic hinge mechanisms, with reduced capacity as corrugations flattened. The Canadian Highway Bridge Design Code, which considers thrust force and bending moment, accurately predicted bearing capacity than the other methods in this study. These findings are vital for optimising design and ensuring safety in horizontal-ellipse corrugated steel utility tunnels.

Agricultural production is facing challenges such as water scarcity, declining soil quality, and excessive use of chemical fertilisers and pesticides, and there is an urgent need to find sustainable solutions. Hydrogel, as a novel functional polymer material, is considered as a potential agro-material to solve these problems due to its excellent water retention, swelling, slow release, biocompatibility and biodegradability. However, there are still challenges in designing efficient agrohydrogels, such as sustainability of the materials, environmental impacts of cross-linking methods, adaptability of the network structure to the crop growing environment, as well as the cost of the materials and the effectiveness of the practical applications. Therefore, a systematic review of the design, properties and applications of agrohydrogels is of great theoretical and practical significance. This paper reviews the design methods of agricultural hydrogels, including network structure design, material source selection, crosslinking technology and its mechanism research. Then, the key properties of agricultural hydrogels, such as water retention, swelling, slow release, biocompatibility and biodegradability, are discussed in detail. Finally, the applications of hydrogels in the fields of soilless cultivation, soil improvement and smart agriculture are presented. This paper concludes that with the continuous progress of technology, agricultural hydrogels will play an important role in future agricultural production.