Light poles or transmission towers may become tilted over the design life, which needs rectifying considering safety and continued use. The jacking pushing method is an efficient way to rectify deviations of these inclined structures supported with rigid piles, but there is a lack of relevant engineering standards and research in this aspect. In this study, a numerical method using FLAC3D is proposed to estimate the required jacking force at the pile top to plumb inclined piles in cohesive soils. Good agreements between the results obtained from the present numerical models and those taken from published experimental and numerical results suggest the reliability of the conclusion. Besides, elaborate parameter analyses including pile geometry, soil properties, and properties of the soil-pile interface are conducted to investigate their influences on the required jacking force. The results can contribute to a safer and more cost-efficient design for rectifying deviations of rigid inclined piles, especially in terms of the required jacking force.

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The strengthening of recycled aggregates is a critical issue, as the low strength of recycled aggregates is the main reason that limits their widespread use. The slurry coating method can strengthen the recycled aggregates by repairing the aggregate surface, but it is hard to improve the internal strength due to the existence of pores and cracks. In this study, a new methodology considering dry mixing with fines to fill and bond the internal pores and cracks before slurry coating is proposed. Twelve strengthened samples considering different combinations of dry-mixing fines and coating solutions were prepared, and the basic physical and mechanical properties were compared, including the water-absorption rate, crushing value, and apparent density with unstrengthened aggregates. The results indicate that the proposed methodology can change the water-absorption rate significantly and improve the crushing resistance and apparent density of the recycled aggregates. A high correlation between the apparent density and the crushing value was also observed. Furthermore, the strengthening mechanism of dry mixing was also investigated by scanning electron microscopy. The micromorphology of the strengthened aggregates indicates that internal pores and cracks can be filled by dry mixing fines and then bonded together after hydration.

With the construction of expressways in eastern Henan, silt has been widely used as a filling material. However, the silt in this area is lacking clay, the content of active oxides in the soil is low, and the soil particles are bonded together. The property is poor, the erosion resistance is not strong, and the direct filling of the roadbed is prone to engineering problems. Due to the obvious regionality of silt in eastern Henan, this paper firstly analyzes the basic physical properties of silt in eastern Henan using compaction, compression, direct shear and particle gradation tests. The research displays that with the increase of the dosage of cement or lime, the optimal water content increases, while the maximum dry density decreases. The compressibility decreases linearly with the increase of the content. The improved soil has a significant increase in large particles. When the dosage of lime is 2%–6%, the improved soil has a good gradation, and the improved soil has a significant increase in large particles. When the dosage is 2%–6%, the improved soil has a good gradation, and the improvement effect on the cohesion is much greater than that on the internal friction angle. The comprehensive analysis of cement lime shows that the dosage of cement should be 4%–6%. In the early stage, the improvement effect of cement on silt is better than that of lime.

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