Research on Construction Technology of Rhombic Hanging Basket at the Limit Distance of High-voltage Transmission Lines

The construction of bridges under the extreme distance constraints of high-voltage transmission lines significantly increases construction difficulty and safety risks. Traditional hanging baskets have higher construction heights, necessitating urgent improvements and optimizations under such conditions. In cantilever bridge construction, the height restrictions of high-voltage transmission lines often challenge the use of traditional diamond-shaped hanging baskets. This study focuses on the construction of the Xinguang Expressway Node Overpass, which adopts a variable cross-section prestressed concrete continuous box girder. The minimum distance from the bottom of the high-voltage line to the bridge deck is approximately 10.5 meters, while the traditional hanging basket construction does not provide sufficient safety clearance. To solve this problem, this study designed a new type of hanging basket by adopting a reverse suspension beam structure, which allows the front upper beam to be installed in reverse suspension, thereby reducing the overall height by 1.5 meters. This ensures a vertical safety distance of 5.65 meters between the construction and the high-voltage transmission lines, meeting both safety and construction requirements. The research results indicate that the new hanging basket not only solves the construction difficulties posed by high-voltage line restrictions but also provides a safe and reliable construction solution, significantly enhancing the safety and efficiency of bridge construction in similar environments.