Circular cut testing method for working stress of concrete members

Abstract

The invention discloses a ring cutting detection method for the working stress of a concrete component. The method comprises the following steps of: measuring a stress value epsilon0 of a detected point of the concrete component, cutting a wire, performing ring cutting at the detected point, connecting the wire to the detected point after the ring cutting, measuring a stress value epsilon1, and calculating the working stress of the concrete component according to a formula sigma=E(epsilon1-epsilon0), wherein sigma is the working stress of the concrete component, and E is the elastic modulus of concrete. When the stress value of the detected point is measured, a wire cutting stress measurement method is adopted, and a hole for the wire to penetrate through is not required to be directly drilled in a detected surface, so that damage to the concrete in a detected area is avoided, and stress loss before test is avoided. According to the method, the structural stress measurement accuracy can reach over 85 percent; and moreover, a ring cutting method is adopted, so that the damage to the concrete is slight, and the detection method belongs to a micro-destructive detection method, and can be conveniently applied to a construction site.

Description

technical field [0001] The invention relates to the technical field of working stress detection, in particular to a ring cutting detection method for the working stress of concrete components. Background technique [0002] That is to say, the actual stress of concrete components is one of the important indicators reflecting its working state and safety, and it is also one of the important parameters of building renovation and reinforcement. Circular shear stress testing is a technique for measuring stress on vertical members of existing buildings. The ring shear stress test can objectively reflect the stress distribution of components under non-destructive (or slightly damaged) conditions, provide scientific data for structural renovation and reinforcement, and ensure the safety of the structure and the stability of the project. It has practical significance and remarkable social and economic benefits. [0003] The ring cut method is also called the notch method. The basic...

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Problems solved by technology

[0004] The existing circumcision method in China is limited to the pre-embedded wire of the test piece under laboratory conditions, or the on-site test of the small component below 500*500mm by the method of passing through the wire, but the application of this method is limited by the size of the component and the difficulty of perforating the wire. Equipment Condition Restrictions

First of all, since the wire work needs to be directly perforated on the detection surface before pasting the strain gauge, the concrete in the ring of the standby inspection area will be loose and damaged and the local stress will be released in advance, thus affecting the accuracy of the test when the ring is cut. Secondly, it is affected by the size of the component, the Reinforcement, concrete strength and equipment conditions limit the perforated wire operation is extremely difficult

At present, there are many high-rise buildings in my country, and the size of load-bearing components is generally large. For large-scale components (above 500*500mm) in existing buildings, it is impossible to use the pre-embedded wire or perforated wire method for on-site stress testing, so the field application of this method has certain advantages. Obvious limitations

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