Research on safety and stability of UHV transmission line foundations under rainfall

doi:10.16265/j.cnki.issn 1003-3033.2021.01.017

Abstract

Abstract: In order to address impacts of rainfall on uplift bearing capacity and safety and stability of UHV transmission line pole and tower foundations, based on load-displacement data obtained from in-situ test and soil parameters obtained from laboratory test, a theoretical model was established according to seepage equation and unified shear strength equation for saturated and unsaturated soils. Then, numerical simulations and analysis were carried out by using the model, and simulation results were found to be in agreement with those of in-situ uplift tests. Finally, based on verified theoretical model, evolution characteristics of seepage field in both unsaturated and saturated soils, development of plasticity zone of soils, and changes in bearing capacity of foundations under different rainfall conditions were studied. The results show that ultimate bearing capacity is related to depth-to-diameter ratio of foundations when infiltration ratio remains the same, and it will be significantly reduced as depth-to-diameter ratio becomes smaller, causing safety and stability of foundations to decline.

Key words: ultra-high-voltage (UHV) transmission lines, pole and tower foundations, rainfall, safety and stability, unsaturated

CLC Number:

X946

DONG Jianjun, YANG Di, ZHENG Gaoyang, XIE Zhengquan. Research on safety and stability of UHV transmission line foundations under rainfall[J]. China Safety Science Journal, 2021, 31(1): 116-124.

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