基于超限学习机的黄土高路堤预拱超填研究  

Research on Overfilling of Pre-arch in Loess High Embankment Based on Over-limit Learning Machine

作　　者：王剑英 王选仓[1] 丁龙亭[1] 曹贵 付林杰 WANG Jian-ying;WANG Xuan-cang;DING Long-ting;CAO Gui;FU Lin-jie(School of Highway,Chang'an University,Xi'an 710064,Shaanxi,China;School of Civil Engineering and Architecture,Heilongjiang Institute of Technology,Harbin 150050,Heilongjiang,China;Gansu Road and Bridge Construction Group Co.Ltd.,Lanzhou 730030,Gansu,China)

机构地区：[1]长安大学公路学院,陕西西安710064 [2]黑龙江工程学院土木与建筑工程学院,黑龙江哈尔滨150050 [3]甘肃路桥建设集团有限公司,甘肃兰州730030

出　　处：《中国公路学报》2018年第11期31-41,共11页China Journal of Highway and Transport

基　　金：甘肃省重大科技专项计划项目(1302GKDA009)

摘　　要：黄土山区公路建设存在大量V形冲沟,使路基产生过大工后沉降,为解决工后超标准沉降问题,减小工后沉降处治成本,需设计路基预抛高(预留沉降量),使公路交工验收时高程符合设计要求。现行规范对如何布设预抛高没有明确说明,因此有必要研究黄土高路堤沉降分布规律,提出其预拱超填方法,针对此类问题依托渭武高速公路工程,通过对试验路历时2年多的沉降观测,得到路基施工期、路面施工期及公路通车1年后的路基沉降数据,提出黄土高路堤沉降随时间和空间的分布规律,得到路堤沿时间及纵、横断面的沉降分布特征,为黄土高路堤填筑末期预抛高的布设形式奠定了基础;基于超限学习机算法,建立黄土高路堤工后沉降预测模型,利用实际沉降观测数据与模型预估结果进行对比,采用平均绝对百分误差对预测结果精度进行评定;最后,通过定量分析填土高度、施工速率、路面重力、路基路面验收时间及交通量修正对路堤工后沉降的影响,提出基于可靠度的黄土高路堤预抛高预测模型及公式,据此给出基于超填平衡的试验路纵、横断面预抛高设置方法,并通过工程实例,验证预抛高模型及公式的准确性。研究结果表明:该沉降预测模型精度良好;研究结果可为黄土地区高填方路基填筑末期预抛高的详细布设提供参考。A large number of "V"type gullies are used in highway construction in the loess mountainous area,which will cause post-construction settlement of the roadbed.To solve the problem of excessive post-construction settlement and reduce the cost of post-construction settlement,it is necessary to design the roadbed pre-throwing height (reserved settlement),to make the highway elevation meet the design requirements at the time of acceptance.The current norm does not clearly explain how to lay out the reserved height.Therefore,it is necessary to study the settlement law of high embankments and propose its pre-arch overfilling method.This study observed the settlement of the Weiwu Expressway for a period of more than two years.The study obtained the settlement data of the roadbed during the construction period,the pavement construction period,and one year after the highway was open to traffic.Based on the obtained data,this study proposed the distribution law of settlement of loess high embankments over time and space.Furthermore,the settlement distribution characteristics of the embankment in the longitudinal and transverse directions were obtained.Finally,the foundation for the layout of the pre-arch of the loess high embankment was laid at the end of the filling period.Based on the algorithm of the over-limit learning machine,a post-construction settlement forecasting model of the loess high embankment was established through a comparison of prediction results with the actual settlement observation data.Furthermore,the accuracy of the prediction results was evaluated using average absolute percentage error.It was verified that the settlement prediction model had good precision.Finally,by quantitatively analyzing the effects of fill height, construction speed,pavement weight,roadbed pavement acceptance time,and traffic volume on post-construction settlement,a pre-arch prediction model and formula based on reliability for high loess embankments was proposed.A method of setting the pre-arch of the test road in the longitu

关 键 词：道路工程 高填方路基 超限学习机 预拱超填技术 路基沉降 沉降规律 

分 类 号：U416.169[交通运输工程—道路与铁道工程]