| 摘要: |
| 胶结砂砾石料是一种新型的且具有广泛应用前景的筑坝材料,但人们对胶结砂砾石料的动力特性缺乏足够的了解。开展一系列胶结砂砾石料的循环动力三轴动力剪切试验,探究了胶结砂砾石料的复杂的动力力学特性,并建立了考虑损伤的动力本构模型。结果表明：胶凝掺量和固结增大会造成动剪模量的提高和阻尼比的减小。在广义Kelvin模型上串联损伤元件,构建了粘弹性损伤模型,基于加载过程中的能量交互规律定义了损伤变量,并修正了动剪模量和阻尼比的理论曲线。推导得出了动力损伤本构模型的刚度矩阵,并证明了本构模型对胶结砂砾石料三轴动力试验具有良好的拟合效果。选取山西守口堡胶结砂砾石坝作动力分析,讨论了坝体在动力作用下的损伤发展规律。 |
| 关键词: 胶结砂砾石料 动剪切模量 阻尼比 损伤特性 动力本构模型 胶凝掺量 |
| DOI： |
| 分类号:TV641;TU452 |
| 基金项目: |
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| Study on dynamic damage characteristics of cemented sand gravel |
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ZHANG Tao1, Ren Honglei2, WU Yingli2
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1.Yellow River Conservancy Technical institute;2.Geotechnical Engineering Department,Nanjing Hydraulic Research Institute
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| Abstract: |
| Cemented-Sang-Gravel represents a novel and promising material for dam construction, yet there remains an insufficient understanding of its dynamic properties. A series of cyclic triaxial shear tests were conducted to investigate the intricate dynamic mechanical properties of CSG. Subsequently, a dynamic constitutive model incorporating damage was developed. The findings indicate that an increase in gel content and confining pressure result in heightened dynamic shear modulus and reduced damping ratio. Furthermore, a viscoelastic damage model was developed by serially connecting a damage element to the generalized Kelvin model, based on the principles of energy interaction during the loading process for defining the damage variable, and refining the theoretical curves of dynamic shear modulus and damping ratio. The stiffness matrix for the dynamic damage constitutive model was derived, demonstrating its strong fitting effects in triaxial dynamic testing of CSG. Finally, a case study involving Shoukoubu CSG dam in Shanxi Province was selected to discuss patterns of damage development under dynamic conditions. |
| Key words: Cemented sand and gravel Dynamic shear modulus Damping ratio Dynamic constitutive model Confining pressure Gel content |
