管桩贯入分层土体的阻力影响特性及预测

Influence characteristics and prediction of resistance of pipe-pile penetrating layered soil

插板机是排水板打设的主要设备。本文利用CEL数值方法研究插板机管桩贯入分层土体时,贯入阻力随深度的变化曲线,通过皮尔逊模型讨论管桩贯入阻力的影响参数,并对贯入阻力的大小进行预测分析。研究结果表明:管桩贯入吹填土层时,贯入阻力随深度增加近似呈线性递增,且不同参数对斜率的影响存在差异;管桩贯入阻力曲线存在明显的转折点,阻力极值在土层分界附近,且参数变化对极值大小的影响不同;当管桩从吹填土层贯入淤泥土层时,贯入阻力急剧减小,后续基本保持不变。吹填土摩擦角与贯入阻力极值的相关性最大,相关系数为0.88。最后,利用分析模型对不同参数条件时的贯入阻力进行预测,模型精度达0.91。

Board insert machine is the main equipment of drainage board.In this paper,CEL numerical method is used to study the penetration resistance curve with depth when the pipe-pile of board insert machine penetrating layered soil.The influence parameters of pipe-pile penetration resistance are discussed by using Pearson model,and the magnitude of the penetration resistance is predicted and analyzed.The results show that the penetration resistance increases linearly with the increase of depth when the pipe-pile penetrating dredged soil layer,and the influence of different parameters on the slope is different.There is an obvious turning point in the penetration resistance curve of pipe-pile,and the position of the extreme resistance value is near the soil layer boundary,and the influence of parameter change on the extreme value is different.When the pipe-pile penetrates into the silt soil layer from the dredged soil layer,the penetration resistance decreases sharply and then basically remains unchanged.The correlation between the friction angle and the extreme value of penetration resistance is the greatest,and the correlation coefficient is 0.88.Finally,the analysis model is used to predict the value of penetration resistance under different parameter conditions,and the accuracy of the model is 0.91.