As the Chinese proverb goes, the spring comes earlier for those who are diligent. At 16:49 on February 26th, 2021, the concrete casting work for the last bored pile of the main bridge over Huayang River in Anhui province, China, has finished as scheduled, which marked the time came for ACEG Road and Bridge Engineering Company Limited, the contractor of the bridge project, to get ready for the construction phase of the superstructures of the bridge in an all-round way.
According to the design, bored cast-in-place piles with a diameter of 2.5 meters were adopted for the underwater foundation of the main piers of Huayang River Bridge; each pier has three piles in two rows and the designed depth of the piles range from 63 meters to 64.5 meters and the boreholes were drilled in method of reversed circulation pumping suction and the vertical piping casting method was used to pour the concrete into boreholes.
The company’s 2.5m diameter borehole and concrete filling techniques have successfully overcome the problems for the project under the complex geological conditions, as large diameter pile drilled with a small drill, shaft wall protection by drilling mud, drilling in an iron grit layer and nuisanceless disposal of the drilling mud, which have the advantages of fast speed, high efficiency and high qualities.
The average distance between the main bridge under construction over Huayang River and the old bridge in operation is less than 0.5m and the pile foundation is located inside the riverbed in poor geological conditions of complex stratums and the construction spaces were limited. Since the commencement of the project in 2019, under the strong supports of the administrative departments at all levels and the technical guidances of several well-known experts of the company and the industry, the new Huayang River Bridge has undergone several design adjustments and optimization, that have resulted in the improvement of the navigable level of Huayang River, better operation safety of the old bridge and less construction investment costs.
The satisfactory completion of the concrete pouring of the main bridge piles provides a time guarantee for the completion of the bearing platform construction before the flood season in 2021 and lays a solid foundation for the completion and delivery of the bridge in the second half of the year. It also provides technical references and demonstration for similar projects in the future.