基于相似理论的地基系数K_(30)室内预估方法及模型试验研究

Research of Indoor Prediction Methods and Model Tests of Foundation Coefficient K_(30) Based on Similarity Theory

地基系数K_(30)是目前我国铁路路基施工质量验收的重要控制指标,由于各地填料土质多变,路基填料压实后的K_(30)能否满足要求无法事先预知,填料选取不当会给现场施工带来不利影响和经济损失。为解决上述问题,基于相似理论提出了一种对填料现场压实后的K_(30)值进行室内预先估计的方法,研制了一套简单宜用的击实样预埋荷载板试验装置,并给出了相应的试验操作规程。经测试,通过在击实土样中预埋荷载板,实现了用直径5 cm荷载板对填料压实后K_(30)值的预先估计,室内预估值与现场测试结果一致,对指导路基填料选择及土质改良具有重要意义。

The foundation coefficient K_(30) is an important control index for the quality acceptance of railway subgrade construction in China.Due to the variety of filler soils in various regions,it could not be predicted whether the compacted subgrade filler K_(30) could meet the requirements in advance.Improper selection of filler would bring adverse effects and economic losses to the site construction.In order to solve the above problems,based on the similarity theory,a method for indoor pre-estimation of K_(30) value after on-site compaction of filler was proposed,a set of simple and suitable embedded load plate test device for compacted samples was developed,and the corresponding test operation procedures were given.According to the test,by embedding the load plate in the compacted soil sample,the preestimation of K_(30) value of the compacted filler by using a small size load plate with a diameter of 5 cm has been realized.The indoor estimated value is consistent with the field test result,which is of great significance to guide the selection of subgrade filler and soil improvement.