杨利国, 邵生俊,等.不同初始静剪应力下压实粉砂土动变形特性研究[J].河南理工大学学报（自然科学版）,2022,41(3):146-151.

YANG L G, SHAO S J,et al.Research on cumulative dynamic deformation characteristics of compacted silty sand under different initial static shear stresses[J].Journal of Henan Polytechnic University(Natural Science) ,2022,41(3):146-151.

不同初始静剪应力下压实粉砂土动变形特性研究

杨利国1,2, 邵生俊1

1.西安理工大学 岩土工程研究所 陕西 西安710048;2.黄河水利职业技术学院 土木与交通工程学院，河南 开封 475003

摘要:为了研究不同初始静剪应力对压实粉砂土动变形和阻尼比的影响，利用空心圆柱扭剪仪进行一系列5 000次的循环动扭剪试验。结果表明：（1）较小的动剪应力作用下，较小的初始静剪应力能紧固土体，减小轴向累积动变形，动剪应力较大作用下，初始静剪应力会加剧轴向累积变形；（2）在循环荷载作用初期，滞回圈的倾斜程度随振次急剧增加，滞回圈面积急剧减小，随着振次增加，不同初始静剪应力的滞回曲线逐渐趋于重合；（3）初始静剪应力对压实粉砂土阻尼比基本没有影响，随着振次增加，阻尼比逐渐降低至基本相同。研究成果可为长期易受较大动应力作用的地基或路基工程设计时控制初始静剪应力、合理确定阻尼比提供参考。

关键词:初始静剪应力;粉砂土;累积动变形;滞回圈;阻尼比

doi:10.16186/j.cnki.1673-9787.2020070038

基金项目:国家自然科学基金资助项目（11572245）；河南省高等学校重点科研项目（21A560009）；黄河水利职业技术学院青年骨干 教师培养计划项目（2019HYGG10）

收稿日期:2020/07/10

修回日期:2020/09/03

出版日期:2022/05/15

Research on cumulative dynamic deformation characteristics of compacted silty sand under different initial static shear stresses

YANG Liguo1,2, SHAO Shengjun1

1.Institute of Geotechnical Engineering， Xi’ an University of Technology， Xi ’an 710048 ， Shaanxi， China;2.Department of Civil and Traffic Engineering， Yellow River Conservancy Technical Institute， Kaifeng  475003 ， Henan， China

Abstract: In order to study the effect of initial static shear stress on the dynamic deformation and damping ratio of compacted silty sand,a series of cyclic dynamic shear tests of total 5 000 cycles were carried out by using a hollow cylindrical torsion shear apparatus. The results showed that:(1) When the small dynamic shear stress acted , the small initial static shear stress could tighten the soil and reduce the axial cumulative dynamic deformation. However, under the action of large dynamic shear stress,the existence of initial static shear stress could aggravate the development of axial cumulative deformation.(2) In the initial stage of cyclic loading , the inclination of the hysteresis loop increased sharply with the number of vibrations, and the area of the hysteresis loop decreased sharply. However, with the number of vibrations increasing,the hysteretic curves of different initial static shear stresses gradually tended to coincide. (3) The initial static shear stress had little effect on the damping ratio of the compacted silty sand, which gradually decreased to the same level with the increase of vibration times. The research results could provide references for controlling the initial static shear stress and reasonably determining the damping ratio in the design of foundation or subgrade which was easily affected by large dynamic stress for a long time.

Key words:initial static shear stress;silty sand;cumulative dynamic deformation;hysteresis loop;damping ratio

不同初始静剪应力下压实粉砂土动变形特性研究_杨利国.pdf