高铁刚性桩-筏地基的固结特性及影响因素  

Consolidation characteristics and influencing factors of rigid pileraft foundation of high-speed railway

作　　者：商拥辉[1,2] 徐林荣[1,3] 陈钊锋 SHANG Yong-hui;XU Lin-rong;CHEN Zhao-feng(School of Civil Engineering,Central South University,Changsha 410075,China;Institute of Architecture and Engineering,Huanghuai University,Zhumadian 463000,China;National Engineering Laboratory for High Speed Railway Construction,Central South University,Changsha 410075,China)

机构地区：[1]中南大学土木工程学院,长沙410075 [2]黄淮学院建筑工程学院,河南驻马店463000 [3]中南大学高速铁路建造技术国家工程实验室,长沙410075

出　　处：《吉林大学学报（工学版）》2022年第7期1588-1597,共10页Journal of Jilin University:Engineering and Technology Edition

基　　金：国家自然科学基金项目(51778634);中国博士后科学基金项目(2020M682589);河南省科技攻关重点研发项目(202102310264);河南省教育厅重点研发项目(20B58003)。

摘　　要：选取高铁常见PHC刚性桩-筏复合地基典型单元体,考虑刚性桩不排水客观特性,分别建立加固区与下卧层土体固结方程,并结合实例深层次揭示地基设计参数对固结特性的影响。研究结果表明:刚性桩-筏复合地基固结具有时变效应,填筑期主要受加固区固结速率影响,静置期主要受下卧层固结速率影响;置换率、相对加固深度和桩-土压缩模量比等设计参数对复合地基固结速率均有影响,临界范围分别为0.03~0.06、0.5~0.8和100~150;本文算法合理性得到验证,研究成果可为软土区高铁刚性桩-筏复合地基设计提供理论依据。The typical unit of PHC rigid pile-raft composite foundation in high-speed railway is selected.Considering the undrained objective characteristics of rigid pile,the consolidation equations of soil in reinforcement area and underlying layer are established respectively,and the influence of foundation design parameters on consolidation characteristics is revealed in depth combining with examples. The results show that the consolidation of rigid pile-raft composite foundation has a time-varying effect. The filling period is mainly affected by the consolidation rate of the reinforcement area,and the resting period is mainly affected by the consolidation rate of the underlying layer. Design parameters such as replacement rate,relative reinforcement depth and pile-soil compression modulus ratio all have an impact on the consolidation rate of composite foundations,and the critical ranges are 0.03-0.06,0.5-0.8 and 100-150,respectively. The rationality of the algorithm in this paper has been verified,and the research results can provide a theoretical basis for the design of rigid pile-raft composite foundations for high-speed railways in soft soil areas.

关 键 词：高速铁路 桩-筏复合地基 固结特性 影响因素 

分 类 号：TU470[建筑科学—结构工程]