Method of constructing new and old concrete bond constraint shrinkage finite element model

Abstract

The invention relates to a method of constructing a new and old concrete bond constraint shrinkage finite element model. The method includes the following steps that a new and old concrete model is built through a linear shrinkage integral unit in ABAQUS finite element software; new concrete is associated with old concrete through definition contact in the new and old concrete model, bond slip between the new concrete and the old concrete is not considered, and bond is simulated through binding constraint; the creep coefficient of the concrete is determined; the change of elasticity modulus along with the age of the concrete is calculated; the bond face of the new concrete is defined to be an auxiliary face in the model, the bond face of the old concrete is defined to be a main face, the shrinkage value is converted into equivalent temperature difference, and calculation is conducted on the new concrete through action of the form of a temperature field. The model constructed by the method can provide a practical analysis model for researches on stress and deformation generated in the new and old concrete bond shrinkage process in reinforcing engineering.

Description

technical field [0001] The invention relates to a method for constructing a finite element model of bonded constrained shrinkage of old and new concrete. Background technique [0002] In the concrete structure, the shrinkage of concrete is an inevitable phenomenon, which refers to the reduction of the volume of the concrete due to deformation under the condition of no force. When the concrete structure is in a free state, such shrinkage is not harmful. However, in the actual reinforcement project, the new and old concrete are bonded to each other, and the shrinkage of the old concrete has basically stopped. If the newly poured concrete shrinks, it will be restrained by the old concrete and cause tensile stress. If the tensile stress exceeds the tensile strength of new concrete or the bonding strength of new and old concrete, cracks will easily occur, which will affect the bearing capacity and durability of the structure. Therefore, it is necessary to establish a simple and...

AI Technical Summary

Problems solved by technology

If the tensile stress exceeds the tensile strength of new concrete or the bonding strength of new and old concrete, cracks will easily occur, which will affect the bearing capacity and durability of the structure.

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