首页|冻融循环对季冻土区粉质黏土-混凝土界面剪切性能的影响

冻融循环对季冻土区粉质黏土-混凝土界面剪切性能的影响

扫码查看
为探究季冻土区粉质黏土-混凝土界面剪切性能,进行了不同冻融循环次数、土体含水率和法向应力的粉质黏土-混凝土二元体冻融循环试验和直剪试验,探讨了界面抗剪强度、抗剪强度参数和抗剪强度损伤度的变化规律.结果表明:直剪试验得到的应力-应变曲线均发生应变硬化现象,可分为弹性变形阶段(剪切位移为0~3 mm)和弹塑性变形阶段(剪切位移为4~15 mm);冻融循环对界面抗剪强度有劣化作用,即通过对土体造成损伤,导致界面内摩擦角和黏聚力下降,从而降低界面抗剪强度;随着冻融循环次数增加,界面抗剪强度损伤度增加,当冻融循环进行0、4次,抗剪强度损伤迅速,冻融循环进行12~20次,抗剪强度损伤较缓,最大界面抗剪强度损伤度为25%;土体含水率的增加对抗剪强度有削弱作用,随着土体含水率的增加,界面内摩擦角降低,但黏聚力先增加后减小,当土体含水率为20.7%时,黏聚力达到最大值;法向应力的增加对抗剪强度有增强作用.
Effect of Freeze-Thaw Cycles on Shear Properties of Seasonal Frozen Soil Area Silty Clay-Concrete Interface
In order to explore the interfacial shear properties between silty clay and concrete in seasonal frozen soil area,the freeze-thaw cycles test and the interface direct shear test of silty clay-concrete binary with different freeze-thaw cycles,normal stress and moisture content of soil were completed,and the changes of interface shear strength,shear strength parameters and shear strength damage degree were discussed.Through direct shear tests,the variation rules on shear properties of the interface and strength parameters were investigated.The results showed that the strain-stress relation underwent strain hardening phenomenon,which can be divided into elastic deformation stage(0-3 mm)and elastoplastic deformation stage(4-15 mm).The freeze-thaw cycles deteriorated the interfacial shear strength,that is,by causing damage to the soil,the friction angle and cohesion of interface were reduced,thereby reducing the interfacial shear strength.With the increase of the number of freeze-thaw cycles,the damage degree of interfacial shear strength increased.However,when the freeze-thaw cycles were 0 and four times,the shear strength damage was rapid,and the damage was slow when the freeze-thaw cycles were 12-20 times,in which the maximum interfacial shear strength damage degree was 25%.With the increase of moisture content of soil,the increase of moisture content of soil weakened the shear strength,the friction angle of interface decreased,however the cohesion first rose and then reduced.When the soil moisture content was 20.7%,the cohesion reached the maximum.The rising of normal stress enhanced the shear strength.

concretesilty clayinterfaceshear propertiesfreeze-thaw cyclesshear strengthseasonal frozen soil area

王伯昕、高银龙、王清、刘佳奇

展开 >

吉林大学建设工程学院,长春 130026

混凝土 粉质黏土 界面 剪切性能 冻融循环 抗剪强度 季冻土区

国家自然科学基金项目国家自然科学基金项目吉林省自然科学基金项目

420722964233070820220101164JC

2024

吉林大学学报(地球科学版)
吉林大学

吉林大学学报(地球科学版)

CSTPCD北大核心
影响因子:1.062
ISSN:1671-5888
年,卷(期):2024.54(5)