1. The scientific and technological field of the project: This project belongs to the field of architectural science and technology. 2. Main technical innovation contents, characteristics and application recommendations (1) The application of the construction technology of installing the A-deformed section steel main tower with high space (108 meters) supports solves the problems of multi-point hoisting, spatial positioning and high-altitude welding of large components. Construction problems ensure the stability and installation accuracy of the tower column during the construction stage, and have strong applicability. The use of high bracket hoisting construction saves 4 million yuan in cost compared with the construction of large lifting equipment, improves the installation accuracy of sections, and ensures the construction quality of the main tower. (2) The application of multi-point continuous pushing technology for long-span (510 meters) single slide flexible high piers with wide deck steel box main beams fills the gap in domestic single slide pushing construction technology and overcomes the flexible support of deep-water light plate river bed. Pier construction, linear control and correction of single slide steel box girder, compared with conventional double slide or multi-slide pushing construction, reduces construction costs, saves materials and materials, greatly shortens the construction period, and forms a single slide flexible high pier with multiple points. Continuous pushing complete construction method has very great economic benefits and practical value. (3) The application of sheet pile support, grouting curtain and anchor-shotcrete combined support technology for ultra-large diameter deep foundation pits under complex geological conditions of dissolved and permeable water has solved the stability and waterproofing problems of large-diameter anchors and ultra-deep foundation pits in dissolved and permeable strata along the river. This comprehensive technology has obvious waterproofing effect on dissolved and permeable strata, and no phenomena such as water leakage and piping occur. The deformation value of the foundation pit is always controlled within the range of early warning values and is safe and controllable, accumulating valuable experience for the construction of similar foundation pits. has good promotion and application value. (4) The application of joint cofferdam construction technology consisting of lock-mouth steel pipe piles, bored piles and rotary grouting piles under complex geological conditions has realized waterless dry excavation of earth and bedrock blasting excavation; at the same time, it has effectively controlled the soil pressure of the bank side flood control embankment prevents the overall displacement of the cofferdam and ensures the safety of foundation pit construction. (5) By using ponto-type water drilling platform for deep-water drilling pile construction technology, the cost is saved by about 2.4 million yuan compared with conventional drilling platform construction, which accelerates the construction progress, shortens the construction period by 30 days, while ensuring the safety of bridge construction during flood season. (6) The application of high-precision installation and positioning construction technology of the pressure plate under the steel main tower using spatial variable cross-section brackets has successfully solved technical problems such as high-precision installation and positioning of large-tonnage steel members and welding deformation control measures, and has good promotion and application value. (7) The application of measurement and positioning technology for the spatial distortion variable cross-section A-type steel box main tower improves the installation and positioning accuracy of segments, ensures the construction quality of the main tower, and has good promotion and application value.