Experimental device for concrete multifactor permanent stability under co-action of pulling stress and surroundings

Abstract

The invention relates to a concrete multi-factor durability test device under the common effect of tensile stress and environment, wherein, the lower part of a pull rod (8) is connected with a lower pull plate (13), the upper part of the pull rod (8) penetrates an upper pull plate (7) and a limit plate (4), the upper pull plate (7) is penetrated on the pull rod (8) to be fixed by a lock nut (6), a screw cap (2) presses a stress sensor (3) on the limit plate by a spherical screw rod (1), a spring (5) is sheathed on the spherical screw rod (1) and is positioned between the limit plate and the upper pull plate, an upper stretching chuck (91) and a lower stretching chuck (92) are arranged between the upper pull plate and the lower pull plate (13), the upper stretching chuck (91) is connected with the spherical head part of the spherical screw rod (1), the lower stretching chuck (92) is connected with the spherical head part of a spherical pull rod (12), a dumbbell-shaped concrete sample (10) is positioned between the upper stretching chuck (91) and the lower stretching chuck (92), the dumbbell-shaped concrete sample is held by the stretching chucks, both sides of the dumbbell-shaped concrete sample (10) are provided with constant force holding instruments (11), and the constant force holding instruments are connected with a non-metallic ultrasonic testing instrument (14).

Description

technical field [0001] The invention relates to a multi-factor durability test method and device for concrete under the joint action of tensile stress and environment, which belongs to the concrete durability test technology. Mainly used in construction, bridges, water conservancy and transportation and other fields. Background technique [0002] For half a century, accidents of premature failure and shortened life of concrete structures due to insufficient durability of concrete structures have continued to increase, especially major projects such as dams, roads, bridges, ports, and high-rise buildings that have not reached the design period. Accidents of destruction occur from time to time, causing huge economic losses and casualties. The research report of the Chinese Academy of Engineering shows that in China, the direct economic loss of concrete structures caused by the corrosion of steel bars is as high as 100 billion yuan per year. Although there have been decades o...

AI Technical Summary

Problems solved by technology

There are two main reasons for this: ①The design and processing of the test device for applying tensile stress is very difficult, and it is difficult to ensure that the axis of the tensile sample coincides with the line of action of the tensile load during the test. Great discreteness; ②The tensile sample and the tensile chuck are prone to stress concentration at the clamping point, causing the sample to fail at the clamping point instead of breaking in the middle

[0005] The above shortcomings severely limit the wide application of direct tensile stress loading devices in concrete multi-factor durability experiments.

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