摘要
钢筋混凝土结构内部初始微裂缝分布和扩展的非线性特征较为明显,合理估计混凝土劣化过程中的损伤范围和裂缝宽度对减少工程经济损失、保证结构安全运行具有重要意义。在建立四参数等效应变和应变空间四参数破坏准则的基础上,求解混凝土结构在复杂多轴应力状态下的损伤变量,通过应变分解方法得到混凝土非连续开裂部分的相关信息后,根据损伤力学和弥散裂缝理论推导结构损伤开裂全过程的裂缝宽度表达式,以四点弯曲梁为例进行有限元计算。结果表明,上述方法能细致描述钢筋混凝土梁从加载到破坏整个受力过程的变形特征和开裂规律,数值模拟结果与试验数据较为吻合,验证了计算模型的合理性和准确性。研究结果可为实际工程中钢筋混凝土结构的维修和加固提供决策依据。
The nonlinear characteristics of the distribution and propagation of initial microcracks in reinforced concrete structures are obvious.It is of great significance to reasonably estimate the damage range and crack width in the process of concrete deterioration to reduce the economic loss of the project and ensure the safe operation of the structure.On the basis of establishing four-parameter equivalent strain and four-parameter failure criterion of strain space,the damage variable of concrete structure under complex multiaxial stress state is solved.After the relevant information of discontinuous cracking part of concrete is obtained through the strain decomposition method,the expression of crack width in the whole process of structural damage and cracking is deduced according to damage mechanics and smeared crack theory.Taking a four-point bending beam as an example,the finite element calculation is carried out.The research results show that the above method can describe the deformation characteristics and cracking rules of the reinforced concrete beam during the whole stress process from loading to failure in detail.The numerical simulation results are in good agreement with the test data,which verifies the rationality and accuracy of the calculation model.The research results can provide decision-making support for the maintenance and reinforcement of reinforced concrete structures in practical projects.
作者
戴永琪
刘晓青
DAI Yongqi;LIU Xiaoqing(Shanghai Investigation,Design&Research Institute Co.,Ltd.,Shanghai 200434,China;College of Water Conservancy and Hydropower Engineering,Hohai University,Nanjing 210098,China)
出处
《水利水运工程学报》
CSCD
北大核心
2023年第6期101-108,共8页
Hydro-Science and Engineering
关键词
钢筋混凝土结构
非线性分析
损伤模型
裂缝宽度
reinforced concrete structure
nonlinear analysis
damage model
crack width
