Our company’s “Key Technologies for the Construction of Long-Span Bridges in Highway Canyon Areas” has been awarded the First Prize for Scientific and Technological Progress by Guizhou Province.

Release time:

2017-11-14 17:04

Source:

Recently, in accordance with the relevant provisions of the “Guizhou Province Science and Technology Award Measures” and the “Implementation Rules for the Guizhou Province Science and Technology Achievement Award Measures,” and following initial evaluations by various specialized subject groups, a comprehensive review by the Provincial Science and Technology Award Review Committee, and approval by the Provincial Department of Science and Technology, our company—acting as the primary completing unit—has been awarded the First Prize for Scientific and Technological Progress of Guizhou Province for 2017 for our project “Key Technologies for the Construction of Large-Span Bridges in Highway Canyon Areas.”

The key technologies for constructing large-span bridges in canyon regions along expressways have systematically explored, with a focus on the complex geographical characteristics of canyon areas, the structural systems and detailing of large-span canyon bridges, critical construction techniques, and high-performance concrete made from mechanism sand. The following major innovative achievements have been attained:

In terms of structural systems

Creatively proposed a new bridge type—the empty-span continuous rigid-frame bridge—and developed a comprehensive set of structural design and analysis methods, thereby breaking through the technical bottleneck that conventional continuous rigid-frame bridges could only span up to 250 meters. For the first time, a steel-truss-concrete composite beam structure was adopted, effectively addressing the structural design challenges posed by the uneven span distribution caused by the steep terrain in canyon regions. Moreover, for the first time, a calculation formula for the width-to-thickness ratio limit of concrete box-shaped arch rings was derived based on stability theory, thus further refining the theoretical framework for arch bridge design.

2. In terms of key construction technologies

By cleverly leveraging the already constructed beam segments, we developed a “longitudinal under-beam incremental launching” technique, enabling the installation of entire segmental units even under canyon terrain conditions. This approach effectively ensures the structural integrity and safety of the project and boosts construction efficiency by 50% compared to conventional methods that involve assembling individual components one by one. We also conducted research on the full-segment lifting and intelligent aerial rotation technology for steel truss main girders using cable systems, successfully resolving the challenge of single-side lifting with cable cranes in suspension bridges and applying this technology for the first time to cable-stayed bridges, thereby significantly enhancing both structural integrity and construction efficiency. Furthermore, for the continuous construction of curved beam (arch) segments in cast-in-place arch bridges, we proposed a feasible domain algorithm for stay-cable forces incorporating a predictive mechanism, which has improved construction safety and precision.

3. In the research on high-performance concrete using manufactured sand concrete

Through research on concrete production processes and model pouring tests, a new “bottom-injection, top-pressurization” technique was adopted for the first time in steel tube concrete arch bridges, effectively addressing the challenges of excessive circumferential forces in the pipe walls during conventional “arch-foot injection” and “top-pressure injection” methods—issues that often led to pipe bursting, blockages, and poor concrete compaction. In addition, a series of mechanism-sand concretes with high strength, high performance, and high pumping head were developed, meeting the requirements of high-pier, high-tower, and high-head pumping construction for canyon bridges.

The project has obtained 35 national patents (including 13 invention patents), published 135 papers—of which 25 are indexed in SCI and 36 in EI—and produced 4 monographs. It has also secured more than 10 provincial- and ministerial-level construction techniques. The research findings have effectively addressed key technical challenges in the construction of large-span bridges across canyons on expressways, leading to the completion of numerous bridges of world-class complexity. These achievements have been widely applied to bridges such as the Beipanjiang Bridge, Liugang River Bridge, and Mupeng Bridge, firmly establishing China’s leading position in canyon bridge construction worldwide and transforming Guizhou into a well-deserved “Bridge Museum” of the world. The application of these project results has yielded significant socio-economic benefits and holds great potential for further widespread adoption and application.

The review panel, led by Chen Zhengqing, unanimously agreed that the project’s research results as a whole have reached an internationally leading level.

(Du Bin, Yang Jian)