Evaluation of Structural Performance of Reinforced Concrete Structures Considering Durability

完成了2000-2002财政年度3年的研究工作，取得的成果总结如下：1.本文的主要研究内容如下：1.收集和回顾了以往关于考虑耐久性的钢筋混凝土结构性能评估的研究成果，明确了本研究的定位和今后需要开展的工作。进行了不同龄期混凝土试件的断裂试验，研究了骨料对断口形貌和断裂模式的影响。此外，对通过本研究建立的被称为“粒子模型”的细观分析模型的微观材料参数进行了评估。考虑识别参数的颗粒模型所获得的结果表明，所提出的颗粒模型能够有效地研究混凝土细观断裂行为。为了提高混凝土结构的延性和抑制损伤，DUC…提出了多瓦纤维增强水泥基复合材料“DFRCC”以及评价其材料性能的方法。然后对DRFCC剪力墙试件和普通混凝土剪力墙试件进行了反复水平荷载作用下的试验和有限元分析，证实了DFRCC剪力墙的延性和强度较RC剪力墙有较大的提高。混凝土浇筑后在硬化过程中，任何混凝土构件都可能产生收缩应变。对考虑收缩应变初应力的钢筋混凝土板的有限元计算结果表明，初应力对钢筋混凝土板的开裂行为有较大影响。此外，利用无损检测方法对受弯破坏的钢筋混凝土梁进行了断裂试验，阐明了损伤的空间分布以及损伤与结构性能的关系。利用宏观模型和有限元方法研究了钢筋混凝土梁的强度和延性的尺寸效应、钢筋混凝土柱抗剪破坏的循环劣化、钢筋混凝土梁柱节点的破坏模式和抗力机理以及剪力墙的三维静力和二维动力性能，并考察了分析方法的有效性和各构件的结构性能。较少

3 years research work from the fiscal year of 2000 to 2002 was completed and the results obtained are summarized as follows.1. The past research results dealing with evaluation of the structural performance of RC structures considering its durability were collected and reviewed to demonstrate a position of the present study and future works to be conducted.2. The fracture test on concrete specimens with different ages was carried out, and effect of the aggregates on the profile of fractured surface and the fracture mode was investigated. In addition, the microscopic material parameters, which characterize a meso-scale analysis model called "particle model" developed through this study, were evaluated. The results obtained by the particle model considering the identified parameters indicate that the proposed particle model is verified to be effective to investigate meso-scale fracture behaviors in concrete.3. In order to enhance ductility and restrain damages of concrete structures, Duc … More tile Fiber Reinforced Cementitious composite called "DFRCC" was developed as well as method for evaluating material performance of DFRCC. Then the test and FE analysis on the shear wall specimens with DRFCC and normal concrete were conducted under cyclic lateral loading, and it was confirmed that ductility and strength of DFRCC shear wall is much improved in comparison with those of RC shear wall.4. Shrinkage strains may be caused in any concrete members during hardening process of concrete after casting. The results on the RC panel calculated by FEM, which takes an initial stress due to the shrinkage strain into consideration, indicate that effect of the initial stress on cracking behavior of the RC panel is significant. Furthermore, fracture test on the RC beams failing in flexure was conducted using the nondestructive testing method, and spatial damage distributions and relation between damage and structural performance were clarified.5. Size effect in strength and ductility of the RC beams, Cyclic deterioration of the RC columns failing in shear, failure mode and resistance mechanism of RC beam-column joints and 3-D static and 2-D dynamic behaviors of the shear walls were investigated using the macroscopic models and FEM, and efficiency of the analysis methods and structural performance of each members were investigated. Less