郑西客运专线路基工程沉降观测方案

研究目的:湿陷性黄土路基施工过程中的沉降观测对确定无碴轨道的施工时间起着决定作用,要对路基沉降作出比较准确的评价,就需要制订一种有效的观测方案。研究方法:首先要配备必要的人员和高精度的检测仪器、确定需要观测的内容、布置合理的观测断面、确定观测频率;沉降观测包括基底沉降观测、水平位移观测、路堤坡脚沉降观测和路堤顶面观测四方面,根据测量结果进行沉降推算,以确定最终沉降值和堆载预压的卸载时间。研究结果:实测沉降推算通常可采用双曲线法和对数曲线法来进行并建立沉降与时间的关系曲线,按实测沉降推算或沉降的反演分析法来分析和推算总沉降量、工后沉降值以及后期沉降速率,并分析推算最终沉降完成时间。研究结论:为路基工程沉降观测提供了一种有效的观测评价方法,希望得到推广。

Procedure for Observation of Subgrade Settlement of Zhengzhou-Xi'an Passenger Dedicated Railway Line

Research purposes: When construction of subgrade is conducted in collapsible oless area,the observation of settlement plays critical role in defining construction time of ballstless track.It requires of working out an effective observation procedure for making accurate evaluation of subgrade settlement.Research methods:First of all,it requires of equipping with necessary persons and high accurate inspection instruments for defining necessary observation contents,laying out rational observation section and defining observation frequence.The settlement observation includes settlement observation of foundation bottom,observation of level displacement,settlement observation of slope toe and observation of embankment top.Based on the measurement result,the settlement is calculated to define the final settlement value and time of unloading heaped preload.Research results:The settlement of real measurement can be calculated by adopting hyperbolic curve method and exponential curve method and the relation curve can be established between settlement and time.The entire amount of settlement,post-construction settlement value and settlement rate in later stage can be analysed and calculated according to the calculation of real measurement or by adopting the inversion analysis method for settlement,and further analysis and calculation are made for the final time of settlement,and further analysis and calculation are made for the final time of settlement complete.Research conclusions:It provides an effective method for observation of subgrade settlement in construction,which can be applied widely.