营口软土地区桩网复合地基沉降规律研究

Research on Settlement Law of Pile-net Composite Foundation of High-speed Railway in Soft Soil area in Yingkou City

为研究滨海软土地区高铁地基的沉降问题，以哈大高铁营口东站附近软土地基处理工程为研究对象，对路基填筑过程和工后长期地基沉降进行观测。利用有限元数值分析软件ADINA建立相应的数值计算模型，研究了地基表面沉降规律。研究表明：地基沉降主要发生在路基填筑施工期内，填筑期的沉降量占总沉降量的70％以上；路基填筑施工过程中，地基沉降曲线呈倒钟形，刺入现象明显，在CFG桩周沉降曲线呈“∩”形。基于现场实测数据，建立了工后长期地基沉降预测模型。对比分析结果表明，路基填筑完工三个月后（大约100d）预测公式精度较高，最终预测沉降量与观测值误差在0．21％～0．56％之间，可以满足工后长期沉降预测要求。上述研究成果将为处理滨海地区高速软土路基工程，预测和控制工后沉降提供了合理的依据。

In order to research the foundation＇s settlement, the soft soil＇s foundation treatment project in Yingkoudong station of Ha＇Da high- speed railway was taken as the research objects. The foundation＇s settlement has been continuously observed during the filling and post con- struction. The calculation model of the foundation has been established by ADINA software and the settlement law of pile-net composite foun- dation was researched. The research results show that the foundation＇s settlement mainly occurs in the embankment filling construction period. The foundation＇s settlement in filling construction period accounts for above 70 percent of the total settlement. The settlement curves show as inverted bell-shaped during the filling construction and has an obvious pierce phenomenon. The settlement curves around the cement fly-ash grave piles show as ＇ rl ＇ shape. The settlement＇s prediction empirical formula of the foundation＇s ground has been established basing on the field monitoring results. The comparison between the results shows that predictor formula has high precision after the embankment filling con- struction about three month or 100 days. The error is between 0.21% - 0.56% between the final predict values and observed values. Its pre- diction precision can meet engineering need. The above research achievements will provide a rational suggestion on the foundation＇s settlement prediction and post-construction control engineering of soft soil subgrade construction in coastal area.