混凝土基本力学性能.ppt

DepartmentofCivilEngineering NUAA 1 高等钢筋混凝土理论 结构工程专业硕士研究生课程 DepartmentofCivilEngineering NUAA 2 本科 钢筋混凝土结构 钢筋混凝土的特点和设计方法 研究生 钢筋混凝土结构 钢筋混凝土结构的主要理论基础和试验依据 DepartmentofCivilEngineering NUAA 3 试验研究 调查统计 理论分析 计算对比 揭示作用机理 总结一般规律 建立数学模型 确定计算方法和构造措施 工程验证 形成规范 从工程中提出问题 钢筋混凝土结构研究方法 DepartmentofCivilEngineering NUAA 4 混凝土基本力学性能多轴强度和本构关系钢筋与混凝土的粘结轴向受力特性抗震性能疲劳性能抗爆性能结构的耐久性 课程内容 DepartmentofCivilEngineering NUAA 5 教材 过镇海 时旭东编著 清华大学出版社 钢筋混凝土原理和分析 DepartmentofCivilEngineering NUAA 6 第一章混凝土的基本力学性能 1 非匀质性和不等向性 1 1混凝土的材性特点 DepartmentofCivilEngineering NUAA 7 2 原因粗骨料和水泥砂浆的随机分布两者的物理和力学性能的差异 DepartmentofCivilEngineering NUAA 8 3 材性的基本特点 微观内应力 变形和裂缝状态复杂 变形的多元组成 应力状态和途径对力学性能的影响 时间和环境的影响微观 复杂宏观 工程精度 DepartmentofCivilEngineering NUAA 9 DepartmentofCivilEngineering NUAA 10 DepartmentofCivilEngineering NUAA 11 Micro crackatInterfaceofAggregateandMortar ExpansionofCrackTip CrackConnecting Damage 4 受力破坏的一般机理 DepartmentofCivilEngineering NUAA 12 1 StandardCubeCompressiveStrengthStandardSpecimen SideLengthis150mm StandardMaintenance Temperature20 3 C Humidity 90 28days StandardLoading LoadingVelocity0 3 0 5N mm2PerSecond isastrengthindextocalibratethegradeofconcrete 1 2CompressiveStrength DepartmentofCivilEngineering NUAA 13 ActuallyisnotAxialCompression DepartmentofCivilEngineering NUAA 14 DepartmentofCivilEngineering NUAA 15 2 PrismCompressiveStrength Specimen150 150 300mm DepartmentofCivilEngineering NUAA 16 DepartmentofCivilEngineering NUAA 17 DepartmentofCivilEngineering NUAA 18 DepartmentofCivilEngineering NUAA 19 峰值应变 DepartmentofCivilEngineering NUAA 20 ControllingValueofCompressiveStaininTest DepartmentofCivilEngineering NUAA 21 弹性模量 DepartmentofCivilEngineering NUAA 22 DepartmentofCivilEngineering NUAA 23 1 3受压应力 应变全曲线 1 试验方法 普通液压试验机上附加刚性元件 应用电液伺服阀控制的刚性试验机进行等应变速度加载 CompleteStress StrainCurve 上升段和下降段 DepartmentofCivilEngineering NUAA 24 弹簧作为刚性元件 DepartmentofCivilEngineering NUAA 25 千斤顶作为刚性元件 DepartmentofCivilEngineering NUAA 26 2 全曲线方程 几种理论曲线 DepartmentofCivilEngineering NUAA 27 DepartmentofCivilEngineering NUAA 28 我国规范 分段式 上升段和下降段 上升段和下降段在曲线峰点处连续 DepartmentofCivilEngineering NUAA 29 DepartmentofCivilEngineering NUAA 30 DepartmentofCivilEngineering NUAA 31 DepartmentofCivilEngineering NUAA 32 DepartmentofCivilEngineering NUAA 33 DepartmentofCivilEngineering NUAA 34 1 4TensileStrengthandDeformation 1 试验方法AxialTensileTest SplittingTest FlexuralTensileTest DepartmentofCivilEngineering NUAA 35 AxialTensileStrength SplittingTensileStrength FlexuralTensileStrength DepartmentofCivilEngineering NUAA 36 2 轴心抗拉强度 DepartmentofCivilEngineering NUAA 37 DepartmentofCivilEngineering NUAA 38 3 劈拉强度 DepartmentofCivilEngineering NUAA 39 4 峰值应变 试验控制拉应变依据 DepartmentofCivilEngineering NUAA 40 5 受拉弹性模量 DepartmentofCivilEngineering NUAA 41 6 受拉破坏过程和特征 DepartmentofCivilEngineering NUAA 42 DepartmentofCivilEngineering NUAA 43 受拉破坏和受压破坏的比较 裂缝方向裂缝数量裂缝形状破坏过程 DepartmentofCivilEngineering NUAA 44 几种混凝土受拉本构模型 DepartmentofCivilEngineering NUAA 45 我国规范 DepartmentofCivilEngineering NUAA 46 DepartmentofCivilEngineering NUAA 47 DepartmentofCivilEngineering NUAA 48 1 5ShearStrengthandDeformation 1 试验方法 DepartmentofCivilEngineering NUAA 49 1 矩形短梁直接剪切 DepartmentofCivilEngineering NUAA 50 2 单剪面Z形试件 DepartmentofCivilEngineering NUAA 51 3 缺口梁四点受力 AB截面弯矩为零 中间段剪力为常值 DepartmentofCivilEngineering NUAA 52 4 薄壁圆筒受扭当筒壁很薄时 为理想的纯剪应力状态 DepartmentofCivilEngineering NUAA 53 5 二轴拉压施加二轴应力 当 2 0 3 1时 与45 方向的纯剪应力状态等效 DepartmentofCivilEngineering NUAA 54 各种试验方法得到的抗剪强度值相差达一倍多 第 1 2 种试件剪切面上的剪应力分布不均匀 且存在较大正应力 第 4 5 种试件接近理论的纯剪应力状态 但一般试验室不易实现 第 3 种方法正应力较小 接近纯剪应力状态 试验值与 4 5 接近 DepartmentofCivilEngineering NUAA 55 2 ShearStrength DepartmentofCivilEngineering NUAA 56 3 ShearDeformationandShearModulus DepartmentofCivilEngineering NUAA 57 ShearStress ShearStrainCurve Departme