Piezoelectric conduit, prestressed tendon pre-tensioning bending device, and prestressed tendon pre-tensioning bending construction method

Abstract

The invention discloses a piezoelectric conduit, a prestressed tendon pre-tensioning bending device, and a prestressed tendon pre-tensioning bending construction method. The piezoelectric conduit is connected into a pipe shape by adopting a piezoelectric plate and an insulating material which are oppositely arranged; a prestressed tendon bending and tensioning mechanism is arranged in the prestressed tendon pre-tensioning bending device; the prestressed tendon bending and tensioning mechanism comprises the piezoelectric conduits used for bending prestressed tendons and force application mechanisms used for applying tension to the piezoelectric conduits to enable the prestressed tendons to be bent and deformed and enable the tension of the prestressed tendons to reach a set range; and the force application mechanisms and the piezoelectric conduits are arranged in a one-to-one correspondence mode. The principle that the piezoelectric conduits generate bending deformation after being electrified with direct current is utilized, and the piezoelectric conduits can be used for tensioning the prestressed tendons, so that damage to the prestressed tendons can be avoided; and bending parameters and tensioning stress of the prestressed tendons can be indirectly controlled by accurately controlling the bending parameters of the piezoelectric conduits, so that the requirements on the bending parameters and the tensile stress of the prestressed tendons under different working conditions can be met.

Description

Technical field[0001]The invention relates to the technical field of civil engineering, in particular to a piezoelectric conduit, a pre-tensioned and bent pre-stressed tendon and a pre-tensioned and bent construction method.Background technique[0002]At present, when the post-tensioning method is used in the construction of pre-stressed tendons, there are problems such as imperfect concrete grouting, blocking control, and out-of-control of the pre-stress, resulting in problems such as cracks and continuous deflection during use of the bridge. Compared with the post-tensioned pre-tensioned pre-stressed concrete construction, the pre-tensioned pre-stressed concrete beam construction technology is simpler, the number of procedures is less, the construction period is shorter, the unit cost is lower, and the construction quality is easier to guarantee. In addition, the pre-tensioning method saves the anchors and corrugated pipes used in the post-tensioning method, and saves the complicate...

AI Technical Summary

Problems solved by technology

The removal of the bender requires manual gas cutting, which is not easy to operate and is extremely dangerous;

[0006] 2) Pull-down bending type: After stretching the prestressed tendons, the prestressed tendons are bent into a specified line shape by applying a vertical force through the device, but when the vertical force is applied, the prestressed tendons often cause certain damage. damage;

[0007] 3) The bending accuracy of the prestressed tendons is not easy to control: when the guided bending method and the pull-down bending method are used to bend the prestressed tendons, the bending parameters of the folded line prestressed tendons cannot be precisely controlled, such as: bending radius, bending starting angle, etc.;

[0008] 4) The design of the bending device is unreasonable: the structure of the currently used bending device is relatively complex, the volume is large, the material cost and processing cost are high, and it is easy to cause stress concentration and cracking on the contact surface with the concrete; The thickness of the plate is limited, the processing is difficult, and the friction is relatively large. It needs to be used with an alloy anti-friction sleeve, and the guide radius is relatively small.

[0009] 5) There is a "rigid hard contact" between the bender and the folded prestressed tendons, the bender is very likely to cause damage to the prestressed tendons at the bending position, and the risk of prestressed tendons breaking during the tensioning process is high

[0010] The core problem is to use the bender to bend the prestressed tendons into a specified line shape, and then use the jack to stretch the prestressed tendons. The risk of damage to prestressed tendons is also greater, so some devices and necessary means are needed to solve the above problems

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