【摘要】 为研究钢管桩内土芯对海上风电超大直径钢管桩水平承载特性的影响,本文首先推导得出土芯竖向荷载作用产生的附加弯矩计算表达式和附加弯矩-转角本构关系解析解.在此基础上采用传递矩阵法解得桩身响应通解.通过与案例对比分析验证了本文解的正确性.最后开展了参数影响分析,结果表明:在容许承载力范围内,考虑土芯作用时泥面处桩身变形降低幅度随着土芯长度、土芯刚度的增加以及土芯重度、桩径和桩嵌入长度的减小而增加,当土芯高度与桩嵌入深度比值为0.8时桩身变形最小.桩侧土强度对泥面处桩身变形影响非常显著,土体强度越低,考虑土芯作用时桩身变形越大且这一不利影响随着土芯高度的增加而显著.当荷载较大时,土芯对桩身变形产生不利影响,桩身变形幅度最大超过5%.因此,在超大直径钢管桩设计和优化过程中建议适当考虑土芯附加弯矩的影响.更多还原

【Abstract】 To examine the influence of soil core in steel pipe-pile on the lateral bearing capacity of super-large-diameter monopile foundation of offshore wind turbine,this paper firstly derives the expression of additional bending moment induced by soil core and establishes the corresponding analytical relation of additional bending moment-slope.Based on these,the generalized solutions for pile responses are obtained by utilizing transfer matrix method.Moreover,the reliability of proposed approach is evidenced during case study during which the results from presented method are identical to those from available literature.Finally,this paper conducts the parametric study; and the corresponding results indicate that compared with the case of ignoring soil core effect,the decreasing ratio of pile deflection at surface ground will increase with increasing the length and stiffness of soil core,and with decreasing soil core gravity,pile diameter and pile embedded length within the range of allowable bearing capacity.Meanwhile,deflection will reach minimum value when the ratio of soil core length to pile embedded length equals to 0.8.Furthermore,the strength of soil mass surrounding pile sides has remarkable influence on pile deflection when considering the soil core effect and this detrimental effect will be more significant as increasing the length of soil core.Ahigher load lever applying on pile head will lead to an adverse impact on pile deflection because the extent of variation ranges up to 5%.Thus,suggestion that the influence of additional bending moment should be properly taken into account during the procedure of design and optimization of super-large-diameter steel pipe-pile.更多还原