摘要
静钻根植桩是近些年国内开发的一种绿色环保的新型桩基,其承载特性复杂且影响因素众多。基于上海深厚软土中的静载试验及关键参数试验,利用ABAQUS有限元软件建立三维数值分析模型,重点分析了荷载在预制桩、水泥土、桩周土之间的传递规律以及扩大头的作用机制,并对影响承载性能的主要因素进行了敏感性分析。计算结果表明,扩大头存在可较大幅度提高抗压承载性能,提高扩大头的扩径率与高度均有利于承载力,且扩径率的影响更有效;随着竹节桩占比的提高,极限承载力稍有提高,但变形增大明显;在试桩水泥土条件下,竹节间距变化对承载力影响不明显,工程中常采用的1m间距可优化;水泥土厚度增大有利于桩基承载力提高,但效率较低。
Pre-bored precast pile with enlarged base(PPEB pile)is a new type of green and environmental protection pile foundation developed in China in recent years,which has complex bearing characteristics and many influencing factors.Based on the static load test and key parameters test in deep soft soil in Shanghai,a three-dimensional numerical analysis model was established by using ABAQUS finite element software.The transfer law of load among precast pile,cement soil and soil around pile and the action mechanism of enlarged base were analyzed emphatically,and the sensitivity analysis of the main factors affecting bearing performance was carried out.The calculation results show that the existence of the enlarged base can greatly improve the compressive bearing capacity,increasing the expanding ratio and height of the enlarged base is beneficial to the bearing capacity,and the influence of the expanding ratio is more effective.With the increase of the proportion of nodular piles,the ultimate bearing capacity increases slightly,but the deformation increases obviously.Under the condition of cement soil of the test pile,the spacing of the neighboring nodules of nodular piles has no obvious effect on the bearing capacity,and the 1 meter spacing used in the project can be optimized.The increase of cement soil thickness is beneficial to the improvement of pile bearing capacity,but the efficiency is low.
作者
凌造
吴江斌
王卫东
Ling Zao;Wu Jiang-bin;Wang Wei-dong(School of Civil Engineering,Guangzhou University,Guangzhou,Guangdong 510006,China;Guangzhou Municipal Construction Group Co.,Ltd.,Guangzhou,Guangdong 510030,China;Underground Space&Engineering Design&Research Institute,East China Architecture Design&Research Institute Co.,Ltd.,Shanghai 200002,China)
出处
《建筑科学》
CSCD
北大核心
2020年第S01期94-102,共9页
Building Science
关键词
静钻根植桩
承载特性
深厚软土
三维建模
Pre-bored precast pile with enlarged base
Bearing characteristics
Deep soft soil
Three-dimensional modeling
