Structure and method for converting stress state of large cantilever basket type prefabricated bent cap

Abstract

The invention provides a structure and a method for converting a stress state of a large cantilever basket type prefabricated bent cap. Temporary prestressed tendons are horizontally arranged at the bottom of the prefabricated bent cap; the temporary prestressed tendons are positioned below a first group of prestressed tendons; the temporary prestressed tendons penetrate through a length directionof the prefabricated bent cap; and the two ends of the temporary prestressed tendons are fixed to the beam ends of the prefabricated bent caps in a tensioning mode, a bent cap bending moment value caused by a part of a permanent prestress can be counteracted by tensioning the temporary prestressed tendons, the bent cap bending moment value caused by the permanent prestress can be recovered by releasing and tensioning the temporary prestressed tendons, and therefore an internal force of the temporary prefabricated bent caps is adjusted. The method comprises the following steps: implementing the structure for converting the stress state of the large cantilever basket type prefabricated bent cap and formulating a tensioning sequence of the prestressed tendons. Conversion of the stress stateof the bent cap in a construction period can be effectively solved, stress requirements of the prefabricated bent cap under different working conditions are met, and structural safety of the prefabricated bent cap in the construction period is guaranteed.

Description

technical field [0001] The invention relates to the technical field of construction of a basket-type prefabricated cover beam in the construction technology of a prefabricated bridge, and in particular relates to a structure and a method for switching a stressed state of a basket-type prefabricated cover beam with a large cantilever arm. Background technique [0002] Because the prefabricated components of the bridge pier cover girder are made into finished concrete products in the factory and transported to the site for installation, there is a big difference from the traditional cast-in-place method, which brings about changes in the construction process and working conditions, mainly including the prefabrication process. conditions, transportation conditions and hoisting conditions. [0003] For prefabricated cover beam components, the method of pouring in the factory is similar to that of conventional cast-in-place, the difference is that the high-altitude support platfo...

AI Technical Summary

Problems solved by technology

The posture and force of the cap beam components under different working conditions are very different from those under the bridge construction conditions, which further leads to changes in the structural force of the components. If the traditional method is still used, it will cause a great safety risk

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