摘要
温度变化对土体性质和行为的潜在影响已成为许多岩土工程设计和应用的重要组成部分。针对粉土中孔压静力触探试验(piezocone penetration test,简称CPTu)的温度效应及部分排水状态,提出了基于小孔扩张理论的计算模型和分析方法。采用一种能够表征粉土强度温度效应的本构模型,给出了完全不排水和排水条件下的解析解;以Bourke粉土为例,分析了温度对扩张压力的影响,揭示了扩张压力随温度升高而减小的规律。采用一种线性映射方法给出了部分排水条件下的小孔扩张半解析解,并基于物理模型试验的结果得出了排水状态与温度的相关关系,建立了考虑粉土温度效应与排水状态的CPTu计算模型。研究了不同贯入速率下温度对CPTu测试结果的影响,结果表明,温度升高导致锥尖阻力与锥肩孔压减小,且变化幅度随超固结比的增加而增大,通过试验结果与计算模型预测结果的对比验证了模型的可靠性。
The potential impact of temperature changes on the properties and behavior of soils is crucial in geotechnical engineering design and applications.A calculation model and analysis method based on cavity expansion theory are proposed to assess the temperature effects and partially drainage conditions of piezocone penetration test(CPTu)in silt.A constitutive model characterizing the temperature effect of silt strength is adopted,with analytical solutions provided for fully undrained and drained conditions.Using Bourke silt as an example,the influence of temperature on expansion pressure is analyzed,revealing that expansion pressure decreases as temperature increases.A semi-analytical solution for cavity expansion under partial drainage condition derived using a linear mapping method.The correlation between drainage state and temperature is established based on physical model test results.Consequently,a CPTu calculation model considering the temperature effect and drainage condition of silty soil is established.This study examines the influence of temperature on CPTu test results at different penetration rates.The results indicate that increased temperature reduces cone tip resistance and pore pressure at the probe shoulder,with the change amplitude increasing as the over-consolidation ratio rises.Finally,the reliability of the model is verified by comparing its predicted results with experimental data.
作者
王宽君
刘彬
莫品强
李国耀
朱启银
沈侃敏
胡静
WANG Kuan-jun;LIU Bin;MO Pin-qiang;LI Guo-yao;ZHU Qi-yin;SHEN Kan-min;HU Jing(Zhejiang Engineering Research Center of Marine Geotechnical Investigation Technology and Equipment,PowerChina Huadong Engineering Corporation Limited,Hangzhou,Zhejiang 311122,China;State Key Laboratory of Intelligent Construction and Healthy Operation and Maintenance of Deep Underground Engineering,China University of Mining and Technology,Xuzhou,Jiangsu 221116,China;School of Mechanics and Civil Engineering,China University of Mining and Technology,Xuzhou,Jiangsu 221116,China;Key Laboratory of Safe Construction and Intelligent Maintenance for Urban Shield Tunnels of Zhejiang Province,Hangzhou City University,Hangzhou,Zhejiang 310015,China)
出处
《岩土力学》
EI
CAS
CSCD
北大核心
2024年第6期1731-1742,1754,共13页
Rock and Soil Mechanics
基金
国家自然科学基金(No.52178374,No.52108356,No.52108359)
徐州市基础研究计划(No.KC22019)
浙江省城市盾构隧道安全建造与智能养护重点实验室开放基金(No.ZUCC-UST-22-09)。
关键词
孔压静力触探试验
小孔扩张理论
粉土
部分排水
温度效应
piezocone penetration test
cavity expansion theory
silt
partially drained
temperature effect
