MODEL TEST ON BEARING DEFORMATION BEHAVIOR OF ENERGY PILE GROUPS IN LOESS SOILS

Cao Weiping; Li Qing; Zhao Min; Li Qingyuan; Luo Longping

doi:10.19912/j.0254-0096.tynxb.2022-1444

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Acta Energiae Solaris Sinica ›› 2024, Vol. 45 ›› Issue (1) : 415-422. DOI: 10.19912/j.0254-0096.tynxb.2022-1444

MODEL TEST ON BEARING DEFORMATION BEHAVIOR OF ENERGY PILE GROUPS IN LOESS SOILS

Cao Weiping¹, Li Qing¹, Zhao Min², Li Qingyuan¹, Luo Longping¹

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Abstract

Based on indoor scaled tests, the thermodynamic characteristics of the pile body and the variation law of the bearing deformation characteristics of the pile foundation under four cycles of cold and hot cycles of energy containing pile groups were studied. The thermal-induced pile-soil temperature, the pile-cap settlement, pile top load, as well as pile skin friction were mainly analyzed. The results show that the temperature in a pile and surrounding soils caused by the cooling-heating cycles at a shallower position below the soil surface is always greater than that at a deeper position. The heat transfer efficiency of the energy pile during heat cycles is higher than in cold cycles. Both the working load applied on the pile cap, and the load on the pile top will also be altered due to the thermal process, which consequently causes the pile cap to be tilted from one direction to another direction. It was also found that the tilting of the cap during the heat cycle is a little more significant than in the cold cycle. The heat cycle-induced skin friction on the upper pile shaft is negative and positive on the lower shaft, and vice versa during the cold cycle.

Key words

energy pile / loess soil / model test / bearing deformation behavior / cooling-heating cycles / heat transfer efficiency / pile cap

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Cao Weiping, Li Qing, Zhao Min, Li Qingyuan, Luo Longping. MODEL TEST ON BEARING DEFORMATION BEHAVIOR OF ENERGY PILE GROUPS IN LOESS SOILS[J]. Acta Energiae Solaris Sinica. 2024, 45(1): 415-422 https://doi.org/10.19912/j.0254-0096.tynxb.2022-1444

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