在海上风电桩基础的打桩过程中,桩周土体强度会产生明显的弱化现象,为明确桩周土体强度弱化影响因素以及弱化规律,开展模型试验模拟打桩过程,研究在不同锤击能量下,不同桩体尺寸情况下,桩身侧摩阻力随着贯入深度的变化规律,建立描述土体强度弱化规律的弱化公式,并通过打桩软件对多个海上风电桩基础工程中大直径及超大直径钢管桩的打桩实测数据进行打桩分析。研究结果表明：在打桩过程中,桩周土体强度的弱化同时受到桩体质量以及锤击能量的影响,桩基质量和锤击能量越大,土体强度弱化程度越高。在打桩的可打入分析中,采用该文所建立的弱化公式可模拟出不同尺寸桩体沉桩时土体强度的折减规律。
Abstract
During the piling process of offshore wind turbine foundations, a noticeable phenomenon of soil strength degradation occurs around the pile. To comprehensively understand the factors and patterns influencing the weakening of soil strength around the pile, model experiments simulating the piling process were conducted. The study investigated the variation in lateral friction resistance along the pile body with penetration depth under different hammer impact energies and for various pile sizes. A degradation formula describing the pattern of soil strength reduction was established. Furthermore, employing piling software, an analysis was performed on field measurements of pile driving for large-diameter and extra-large-diameter steel pipe piles in multiple offshore wind turbine foundation projects. The research results indicate that during the piling process, the weakening of soil strength around the pile is simultaneously influenced by both pile mass and hammer impact energy. The higher the pile mass and hammer impact energy, the greater the degree of soil strength reduction. In the analysis of pile drivability, the degradation formula established in this study can simulate the reduction pattern of soil strength during the piling process for piles of different sizes.
关键词
海上风电场 /
桩基础 /
打桩 /
土体强度弱化 /
模型试验
Key words
offshore wind farms /
pile foundations /
pile driving /
attenuation of soil strength /
model test
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基金
国家自然科学基金杰出青年基金（51825904）
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