珊瑚礁砂参数变异性对管桩基础承载特性影响研究

Study on the Impact of Coral Sand Parameter Variability on the Bearing Capacity of Pile Foundation

为研究岩土工程随机有限元分析过程中珊瑚礁砂参数变异性对管桩基础模拟结果的影响,设计了两种不同的随机场单元分布形式,利用Plaxis3D有限元软件进行随机有限元建模,进而分析了模型模拟得到的珊瑚礁砂土体最大、最小土应力分布,土体位移云图,管桩荷载-位移曲线以及桩基础的极限承载力,并将极限承载力与室内模型箱的试验结果数据进行了对比。结果表明,在随机有限元模拟的过程中,当土体参数变异系数较小时,可以通过减少采样样本来提升模拟的效率。在受力较集中的部分,增大土体参数空间分布的变异性,可以提高模型建立的准确度。对珊瑚礁砂参数变异性不同的两种随机场模型极限承载力与试验极限承载力进行误差分析,桩-土接触区域土体参数变异性较大模型的误差值比变异性较小的减小了近12%。

To investigate the impact of coral sand parameter variability on the simulated results of pile foundation using random finite element analysis in geotechnical engineering,two different distributions of random filed units were designed.The Plaxis3Dfinite element software was used for random finite element modeling.The maximum and minimum stress distributions,displacement contour maps,load-displacement curves,and ultimate bearing capacity of the pile foundation were analyzed based on the model simulation.The ultimate bearing capacity was compared with the experimental results from an indoor model box.The results show that,in the process of random finite element simulation,when the coefficient of variation of soil parameters is small,the simulation efficiency can be improved by reducing the sampling samples.In areas where the force is more concentrated,increasing the variability of soil parameter spatial distribution can improve the accuracy of the model.The error analysis of the ultimate bearing capacity calculated from the two different random field models with different variabilities of coral sand parameter shows that the error of the model with larger variability in the pile-soil contact area is reduced by nearly 12%compared to the model with smaller variability.