Analysis on the Construction Process of Newly Built Prestressed Concrete Channel Girders Passing Through the Existing Liaison Line

DOI: https://doi.org/10.62517/jcte.202506103

Author(s)

Pengyuan Yao1,*, Jianjun Wang1, He Zhang2,*, Shixian Ren2, Shixun Jia2

Affiliation(s)

1Gansu Building Materials Research and Design Institute Co., Ltd, Lanzhou, China 2Lanzhou Bowen College of Science and Technology, School of Civil Engineering, Lanzhou, China *Corresponding Author.

Abstract

When the new pre-stressed bridge project crosses the existing engineering routes for construction, the girder-making location affects the construction of Lanzhou subway and the opening of subway on schedule. Therefore, how to effectively shorten the construction cycle and reduce the impact on the construction of Lanzhou subway under the premise of ensuring construction safety and quality has become an urgent problem. In view of this problem, with the background of construction of new prestressed concrete channel girders under the existing liaison line, it is proposed to tension the prestressing bundles when the concrete strength and elastic modulus of the girders reach 75% of the design strength, and the study shows that: when the C55 concrete strength of the channel girders reaches 75%, it is safe to tension the prestressing tendons and feasible to push the construction of the girders laterally; this scheme can be realized through scientific and reasonable construction organization and process adjustment. Through scientific and reasonable construction organization and technological adjustment, this scheme can realize the harmonious coexistence of the newly built prestressed concrete channel girder and the construction of Lanzhou Metro, and at the same time ensure the construction progress and project quality. This program can not only shorten the construction period, but also ensure the construction safety and project quality. The results of the study have important reference value and practical significance for other similar projects.

Keywords

Prestressing; Concrete; Channel Girders; Construction Techniques

References

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