2016年3月上第45卷第5期
D0I10.7672/sgjs2016050069
施工技
术
CONSTRUCTIONTECHNOLOGY
路堤荷载下高速公路复合地基沉降特性及
预测方法研究* 王昌丽'，朱振生"，丁选明"2
（1.河海大学岩土力学与授坝工程教育部重点实验室，江苏南京
210098
2.河海大学水资源高效利用与工程安全国家工程研究中心，江苏
210098) 南京
【摘要】软土地基沉降控制是高速公路建设中的关键技术间题。依托南京长江四桥北接线工程，基于实测沉降数据，采用PLAXIS软件对典型断面路堤荷载下的承载变形特性进行了数值模拟，将沉降计算值与实测值进行了对比分析，揭示了高速公路湿喷桩复合地基加固软基沉降特性和机理，并对湿喷桩复合地基方法处理的软基沉降的预测方法进行了对比分析。
【关键词】公路工程；高速公路；复合地基；沉降；预测；数值模拟
【文章编号】1002-8498（2016)05-0069-05
中图分类号】U416.1
[文献标识码］A
StudyontheSettlementCharacteristicsandPredictionMethodsof the
ExpresswayCompositeFoundationUnderEmbankmentLoad
Wang Changli'，Zhu Zhensheng',Ding Xuanming'2
(1. Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering, Hohai Unitersity, NanjingJiangsu210098, China; 2. National Engineering Research Center of Water Resources Eficient
Utilization and Engineering Safety, Hohai Uninersity, Nanjing,Jiangsu 210098, China)
Abstract:The settlement of soft foundation is the key technology problem in expressway construction. Based on the measured settlement data of the Fourth Nanjing Yangtze River Bridge engineering, the bearing and deformation mechanisms of the typical sections are analyzed by PLAXIS software. The numerical simulation results are compared with the field measured results to verify the validity of the numerical simulation method. Furthermore, the settlement characteristics and mechanisms of soft foundation reinforced by wet spraying cement-soil mixing piles are revealed. The settlement prediction methods of the wet spraying cement-soil mixing pile composite foundation are also studied.
Key words:road construction;expressway; composite foundation; settlement;prediction; simulation
工程地质概况 1
1.1土层分布
本文依托工程为长江四桥北接线中N1标段。从地质勘测结果可以得出，N1标段中K2+000-K5+300段路基处于山冈地区，长度为3.3km。沿线地势相对高亢，地面波状起伏。地面高程 13.000~19.000m，岗间洼地地面高程8.000 12.000m。岗地分布区①。层表土之下即为上更新统③，层老黏性土，埋藏浅，层位稳定，厚度大，层厚达60m（未揭穿），土质良好；岗间洼地区地势低洼，浅部为全新统①，层软土，软土沿新禹河分布，埋藏
·国家自然科学基金项目（51420105013;51378177）
【作者简介】王昌丽，硕士研究生，E-mail；15295532328@163.com
【收稿日期】2015-03-09 万方数据
69
浅，层厚3~13.6m，其下为上更新统③，层老黏性土。该段中桩号K2+960及桩号K3+0402个断面的土层分布及静力触探如图1所示。
维头用力g,×10kP 侧建库用力AP
@,± f8
①，整况质检质费土， ②，粉质黏土
ST
130260390
a K2+960
图1
@,粘土 ①,粉±
维头阻力g,×10kPs 侧壁摩阻力>/Ps
①激况质粉质整土@,粉质点土
b K3+040
K2+960与K3+040桩号静力触探（单位：m）
Fig.1
The cone penetration test for strake
number K2 + 960 and K3 + 040(unit : m)