Soil reinforcement experiment inside large-scale bucket foundation in muddy soil

Abstract

The large-scale bucket foundation with 30 m in diameter and 6 m in height was used as the foundation of wind turbine. The wide-shallow foundation is different from the traditional bucket foundation with high ratio of height to diameter. The cover-load-bearing mode of the new type foundation can resist more external loadings. To achieve the bearing mode, the muddy soil inside the bucket should be reinforced, which will improve the soil strength and make the soil and foundation into a whole part to resist the external loadings. The vacuum and electro-osmotic soil reinforcing methods were used in the experiments. The results showed that the bearing behavior of the muddy soil were effectively improved by the negative pressure and electro-osmotic effect, and the improved muddy soil with better strength could work together with the bucket foundation, meaning that the top-cover bearing mode of the new bucket foundation was achieved. During the soil reinforcing process, the foundation moved downward, i.e., the settlement of foundation was almost finished during the pre-loading process caused by the vacuum and electro-osmotic method.

Keywords

bucket foundation / cover-load-bearing mode / vacuum / electro-osmotic method / consolidation / muddy soil

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