玄武岩纤维改良土应变速率效应试验研究
Experimental Study on Strain Rate Effect of Basalt Fiber-reinforced Soil
牛巍崴 1刘建坤 2郑媛媛 3任志凤3
作者信息
- 1. 中山大学土木工程学院,广东广州 510275;沈阳工学院能源与水利学院,辽宁沈阳 113122
- 2. 中山大学土木工程学院,广东广州 510275;隧道工程灾变防控与智能建养全国重点实验室,广东广州 510275
- 3. 中山大学土木工程学院,广东广州 510275
- 折叠
摘要
为深入研究不同加载速率对玄武岩纤维改良土力学性质的影响,以掺入0.25％、0.5％和0.75％玄武岩纤维的青藏高原粉质黏土为研究对象,对改良土进行不同围压、不同应变速率下的不固结不排水三轴试验,分析在不同的纤维掺量、不同的应变速率下改良土的应力-应变关系、破坏强度及抗剪强度指标的变化规律.研究结果表明:改良土的应变速率效应与土骨架自身的黏滞性和固结程度等因素有关;改良土在不同围压和加载速率下,其应力-应变关系均呈应变硬化特性;破坏强度和抗剪强度随加载速率的增加并不是呈现单调增大趋势,而是存在明显的临界点;纤维含量越高,应变速率对破坏强度的影响程度越显著.综上分析得出应变速率对改良土各力学参数的影响规律,可为今后工程应用提供技术参考.
Abstract
To study the effect of different loading rates on mechanical properties of basalt fiber-reinforced soil,0.25％,0.5％,and 0.75％basalt fiber were added into silty clay from the Tibetan Plateau,and unconsolidated undrained triaxial tests were carried out under different confining pressures and strain rates.Moreover,the influence of strain rate and the fiber content on the stress-strain relationship,failure strength and shear strength were discussed.The experimental results indicated that the strain rate effect was affected by soil viscosity and consolidation degree;the strain hardening property was found in the stress-strain relationship of fiber-reinforced soil under different conditions;the failure strength and shear strength didn't increase monotonously with the increase of loading rate,but there were critical points;the higher the fiber content was,the more significant the effect of loading rate on the failure strength was.Based on the above analysis,the influence law of strain rate on the mechanical parameters of reinforced soil were obtained,which could provide technical reference for future engineering applications.
关键词
路基工程/应变速率/玄武岩纤维改良土/三轴试验/抗剪强度/应力-应变曲线Key words
subgrade engineering/strain rate/basalt fiber-reinforced soil/triaxial test/shear strength/stress-strain relationship引用本文复制引用
基金项目
高速铁路轨道技术国家重点实验室项目(2019YJ199)
冻土工程国家重点实验室开放基金(SKLFSE202104)
出版年
2024
NETL
NSTL
万方数据