Applied Mechanics and Materials Vols. 438-439

Abstract: The correct and reasonable calculation of the structural reliability is the theoretical basis of the design, construction and use of the structure. The research is focused on the development of computing methods of reliability of structural members and system, and also points out the merits and problems of the existing methods with respect to the analysis of the present researches on structural reliability. Meanwhile, the summarization of the development and the existing problems on the reliability of time dependent structure has been provided. Furthermore, it proposes that correlation is the common problem in the computing of structural system reliability, and probes into the correlation coefficient of the calculation and the effects that correlation coefficient exerts on random variables and different systems. The conclusion shows that the specification of the adaptation range of calculation methods and reducing the effects of correlation coefficient contribute to the insurance of the structural safety.

Abstract: The yield status and ultimate status are two very important performance statuses during the loading process of reinforced concrete (RC) members. The yield status and ultimate status can be determined by inspecting the deformation properties of reinforced concrete members. This paper describes four methods to determine the yield status of reinforced concrete members, and three methods to determine the ultimate status of reinforced concrete members. Through these methods, we can understand the mechanical behavior of reinforced concrete members.

Abstract: Chloride ingress is a major factor affecting durability of reinforced concrete structures. In the present study, service life of a RC flexural member in chloride environments is predicted. First, model for service life is established considering model error and the coupling effects of loading condition and environmental factors on the chloride penetration. Then, service life is predicted in probabilistic framework of Monte Carlo simulation. The results show that the use of a lognormal distribution for the service life seems relevant; the service life shows a great scatterings.

Abstract: In the reinforced concrete structure, steel corrosion is a major factor affecting the durability of existing structures, it is necessary to explore the extent of steel corrosion in order to take the necessary measures. Based on non-damaged concrete components or structures, by measuring the performance of concrete-related physical quantities, non-destructive inspection could presume strength, compactness, uniformity and defects of concrete components or structure. Combined with engineering example, non-destructive inspection technique and its application in the degree of steel corrosions inspection have great prospects through further validation.

Abstract: Through earthquake simulation experiment of nine regional confined concrete columns with different axial compression ratio, the bearing capacity and seismic behavior of regional confined concrete columns were studied in this paper. Considering the ductility, stiffness, energy-dissipation performance and related factors of regional confined concrete columns under different axial compression ratio, by comparative analysis of the hysteretic behavior of the specimens, the limit of axial compression ratio of regional confined concrete columns is proposed for seismic design.

Abstract: Nonlinear three-dimensional finite element method was used to analyze the crack pattern and stress distribution of reinforced concrete frame exterior joints with T-section columns. On the basis of the smear-crack approach, the cracking of reinforced concrete joint was predicted. And the capability of finite element model was demonstrated by comparing the predictions with test results. Further analysis was carried out to study the effect of axial load ratio and limb length on stresses of the joints. It is seen that the stresses of joint were influenced by these two factors, which should be considered in the design of reinforced concrete joint with T-section column.

Abstract: According to the mechanical analysis of reinforced concrete (RC) joint with special-shaped column, the formula of crack resistance considering the effect of flange length was derived on the basis of the elasticity theory, and the expressions for calculating the frame joint core effective height and width were presented. Furthermore, four RC joints with special-shaped columns were tested under low cyclic loading to investigate the mechanical behavior. At last, the calculated results predicated by the proposed formula are compared with that by experiments, and indicate that the expression has good applicability.

Abstract: An axial compression test was conducted to study the bearing capacity of the grouted connection with shear keys, and the curve of axial load vs displacement was got. Based on the experiment results, the crack distribution and damage zone of the cement grout is analyzed. With a proper design of the shear keys, grouting material and pipe structure, the grouted connection can achieve a good bearing capacity and ductility. A simplified finite element model was also set up to simulate the local behavior of the grouted connection. And, the numerical result is verified with the experiment phenomenon. This study can be a reference for the design of grouted connection.

Abstract: t is essential to study the performance of reinforced concrete short column. In this paper, the main reinforcements and hoopings in short columns were replaced by C-BAR reinforcements, the regularity of reinforcing bar replaced by C-BAR reinforcements was summarized. The results show that the axial compression bearing capacity of concrete short column is increased.

Abstract: Axial compression ratios of L-shaped columns with different directions of neutral axis were calculated by numerical method. It can be found that the axial compression ratio reaches the minimum value when neutral axis is parallel to the section edge and the shorter limb is compressed, the section scale has little influence on the axial compression ratio of L-shaped columns. On the base of analysis, axial compression ratios of L-shaped columns with different limb lengths are given out.