摘要
国外一高速铁路建设过程中中断了施工并更改了设计标准。为掌握其路基压完状态,通过分层开挖分层原位测试,研究动力触探(DPT)锤击数N_(63.5)分别与压实指标——压实系数K、动态变形模量E_(vd)和地基系数K_(30)的关系。结果表明:路基压实指标随DPT锤击数增加而不断增大,土体压密程度变大导致压实指标随DPT锤击数增长率降低;根据压实指标K,E_(vd),K_(30)与N_(63.5)关系曲线发展特征,建立了路基压实指标DPT分析模型,通过现场实测数据验证了模型预测能力,并提出具有95%可靠度的K,E_(vd),K_(30)分别与N_(63.5)的关系的修正模型。研究成果已在国外推广应用,大幅节约了工程投资。
The construction of an overseas high speed railway was interrupted and the design standard was changed.In order to obtain the compaction state of subgrade,the model relationships between dynamic penetration test(DPT)hammering counts N63.5 and compaction indexes K,K30 and Evd were studied through layered excavation and layered insitu test.The results show that the compaction index of subgrade increases with the increase of DPT hammering counts,and the increase of soil compaction degree will lead to the compaction index decreasing with the increase of DPT hammering counts.According to the curve development characteristics of compaction index K,Evd,K30 with N63.5,the DPT analysis model of subgrade compaction index was established.The prediction ability of the DPT analysis model was verified by the field measured data,and the modified models of K and N63.5,Evd and N63.5,K30 and N63.5 with 95%reliability were proposed.The research results have been applied in a highspeed railway abroad,which greatly saves the project investment.
作者
芦巍
LU Wei(China Railway 21st Bureau Group 4th Engineering Co.Ltd.,Xi’an 710065,China)
出处
《铁道建筑》
北大核心
2020年第9期97-100,共4页
Railway Engineering
关键词
高速铁路
路基工程
压实状态
动力触探
分析模型
high speed railway
subgrade engineering
compaction state
dynamic penetration test
analysis model
