Evaluation of Structural Performance of Reinforced Concrete Structures Considering Durability

从2000年至2002年的3年研究工作已经完成，所取得的成果总结如下.本文的主要工作如下：1.总结和回顾了以往在考虑耐久性的钢筋混凝土结构性能评估方面的研究成果，提出了当前研究的方向和今后的研究方向.对不同龄期的混凝土试件进行了断裂试验，研究了骨料对混凝土断裂面形状和断裂模式的影响。此外，微观材料参数，表征一个介观尺度的分析模型，称为“颗粒模型”，通过这项研究，进行了评估。考虑所识别参数的颗粒模型计算结果表明，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 关于我们 提出了纤维增强水泥基复合材料（DFRCC）及其材料性能评价方法。通过对掺粉煤灰纤维混凝土剪力墙和普通混凝土剪力墙试件在低周反复荷载作用下的试验和有限元分析，证实掺粉煤灰纤维混凝土剪力墙的延性和强度较普通混凝土剪力墙有较大提高.任何混凝土构件在浇筑后的硬化过程中都可能产生收缩应变。考虑收缩应变引起的初始应力的有限元计算结果表明，初始应力对钢筋混凝土板的开裂行为有显著影响。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，研究了损伤的空间分布规律以及损伤与结构性能的关系.采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、钢筋混凝土柱的循环破坏、钢筋混凝土梁柱节点的破坏模式和受力机理以及剪力墙的三维静力和二维动力性能，分析了各种分析方法的有效性和各构件的结构性能。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