Papers by Author: Xiang Dong Wang

Abstract: With progress of the computer technology and numerical simulation method, the numerical simulation of the fracture process of concrete materials has become possible. In this paper, the numerical simulation models of the two types of samples were carried out with the SOLID65 concrete element based on the ANSYS software platform. According to the results, the non-linear characteristic of the concrete material exhibited in the loading process is reflected by the phenomenon that the slope of the later stage shows some reduction in the simulated load - loading point displacement curve. That is to say, the behavior of the appearance and development of cracks can be simulated with SOLID65 concrete element in ANSYS.

Abstract: The carrying capacity decreases continuously as the material property deteriorates under the action of some external factors. It is important to evaluate the damage of concrete, in which the damage parameter plays an important role. An experimentation method is designed in this paper, with which we can simulate the initial damage by mixing initiator into concrete. Using the elastic modulus of axial tension experimentation, the tension initial damage D0 and tension damage Peak value Df have been gained. The Size effect of concrete tension damage parameters is verified. The curve of damage-parameters and size is gained, the trend of the tension damage parameters is obtained.

Abstract: The bearing capacity decreases continuously along with the deterioration of material property under the action of external effects. It is important to evaluate the damage of concrete, and the damage parameter plays an important role in this process. An experimentation method has been designed, which can simulate the initial damage by mixed initiator into concrete. Using the elastic modulus of axial compression experimentation, the initial damage D0 and damage threshold value Df have been gained. The Size effect of concrete compress damage parameters is verified.

Abstract: Many damage models of concrete have been put forward till now, of which some models are applied in engineering practices. The damage parameters play an important role in the calculations of damage with these models, which is determined during experiments. However, the tests of damage on concrete are rarely made, especially about the measuring method of initial damage. The initial damage is an essential parameter to study on the damage of concrete. Being based on the theory of damage, this paper analyze of the damaged and undamaged elastic modulus of concrete. The new method of determining undamaged elastic modulus from test results has been put forward, and then the initial damage has been quantified.

Abstract: Damage parameter of concrete is widely used in design and construction of concrete structures. An experimentation method has been designed, which can simulate the initial damage by mixed initiator into concrete. Damage parameter can be obtained in laboratory with standard specimens. But practical structure is very large. It is not rational to use this parameter in practical structures. So size effect on damage parameter is studied. It is concluded that initial damage and summit damage grow with the increase of structure size, but the growth rate becomes gentle with size increasing. When the size is larger than 500 mm×500 mm, the growth rate is less than 15‰, so the results obtained from specimen in 500 mm×500 mm can be used for mass concrete structures.