DASJ-2 to DASJ-5 Contract Section of the Duyun to Shangri-La Expressway (Guizhou Section) – Duyun to Anshun Segment

Project Overview:

The Duyun-Shangri-La Expressway (Guizhou Section), specifically the Duyun-Anshun segment, was completed and opened to traffic in December 2020. It is the only national expressway whose starting point is located entirely within Guizhou Province. The highway has a total length of 276 kilometers, with a total estimated investment of approximately 43.079 billion yuan. This project represents the largest single infrastructure undertaking in the history of highway construction in Guizhou Province.

The DASJ-2 and DASJ-5 design contract sections of the Du'an Expressway were designed by our company. The total length of the route is 97.106519 km, traversing a variety of landform types with complex topography and geology, and characterized by numerous controlling factors. During the survey and design process, we encountered numerous technical challenges. Through persistent efforts to overcome these difficulties, we successfully resolved multiple technical problems and achieved a wealth of innovative results, including one world-first achievement. The project boasts numerous design highlights and has laid a solid foundation for its smooth construction.

The Du'an Expressway is the only highway in Guizhou selected for the Ministry of Transport’s Green Highway Project, BIM Technology Application Demonstration Project, and Quality Engineering Breakthrough Initiative—Quality and Safety Micro-Innovation Demonstration Project. It is also a quality engineering project and a steel structure bridge demonstration project under the provincial Department of Transportation. Moreover, it is a key project being developed as part of the “Colorful Guizhou—Most Beautiful Expressway” and “Colorful Guizhou—Safe Expressway” initiatives.

Project Highlights:

1. Systematically proposed the “Seven Principles” for core geological route selection design: the principle of respecting natural laws, the principle of prioritizing geology, the principle of feasibility, the principle of safety, the principle of economy, the principle of technicality, and the principle of sustainable development. Within the “principle of technicality,” we pioneeringly identified the core guidelines for tectonic geological route selection, clearly defining the selection principles for areas characterized by synclinal structures, anticlinal structures, fault structures, and dome structures. We also outlined the key factors influencing tectonic geology and provided corresponding precautions, thereby refining the technical guidelines for selecting bridge locations in valley (gully) settings. Based on this innovative theory, rational geological route selection has helped save approximately 735 million yuan in project investment.

2. For the first time, BIM technology has been comprehensively applied throughout the entire highway survey and design process: The Duan'an Expressway is among the first batch of BIM application demonstration projects approved by the Ministry of Transport. Concepts such as ecological protection, low-carbon efficiency, high-quality tea tourism, and technological advancement are the guiding principles upheld by the Duan'an Expressway as a green highway demonstration project under the Ministry of Transport. The Duan'an Expressway has fully integrated BIM technology into the highway construction process, striving to create a modern, green expressway model characterized by “ecological tea tourism and premium Duan'an products,” thereby setting a new benchmark for the construction of “Colorful Guizhou—The Most Beautiful Expressway.” This project is the first to accurately present environmental models of corridor zones using the “BIM+GIS” approach, creating BIM models at the scheme level and conducting comparative analyses. Combined with rapid engineering-scale statistics, this approach facilitates adjustments to various schemes based on environmental factors such as geology, impact zones, and protected areas. Furthermore, Guizhou Expressway has, for the first time, undertaken detailed BIM design for special structures, effectively reducing rework and enhancing design efficiency.

3. Design of the World’s Tallest “H”-Shaped Bridge Tower—the Yunwu Super Bridge: The Yunwu Super Bridge (originally named the Laomian River Super Bridge) is a key project on the Duan’an Expressway, spanning the Laomian River. The right span of the bridge has a total length of 1,718.5 meters, while the left span measures 1,720 meters in total length. The main span of the Yunwu Bridge is a 480-meter-long cable-stayed bridge with twin towers and dual cable planes, featuring combined beam structures. The bridge tower on the Anshun side stands at 300 meters tall—placing it fourth tallest among similar concrete towers worldwide and first in the world among “H”-shaped bridge towers. Consequently, its surveying and design process encountered numerous globally challenging technical issues. The design team successfully overcame several major technical hurdles, including the design of large-diameter deep-bored pile groups, the design of massive-volume concrete foundations, and the design of the “H”-shaped reinforced concrete bridge towers, thereby promoting the industrialized and prefabricated design approach for high-tower, long-span bridges in mountainous regions.

4. Creation of Green Highways and Quality Projects: Green and sustainable development, low-carbon and eco-friendly economies have become the primary directions for sustainable development. We are integrating the nation’s goals of energy conservation and emission reduction into highway design itself, thereby innovating in both design guiding principles and working philosophies. As the only green highway project and quality engineering breakthrough initiative—serving as a demonstration project for micro-innovations in quality and safety—selected by the Ministry of Transport in Guizhou Province, the Du'an Expressway has embedded green and quality design concepts throughout its entire design cycle. The project’s acceptance and inspection indicators upon completion have fully met excellent standards.

5. Demonstration of Green Highways: Creating the “Six Scenic Views of Duan” — The Duan Expressway is a green highway demonstration project sponsored by the Ministry of Transport. Stretching through the majestic mountains and valleys of Qiannan Prefecture, it is surrounded by stunning natural landscapes and passes through regions rich in both natural and cultural tourism resources. The key to creating a green highway that truly embodies Guizhou’s distinctive character and highlights the unique culture of the Qiannan area lies in its landscape design. In the expressway’s design, we pioneered segmented landscape development tailored to local characteristics, thereby realizing the “Six Scenic Views of Duan,” including “Rustic Charm of Green Fields,” “Fragrant Trails Among Pine Groves,” “Elegant Rhythms of the Qingjiang River,” “Windy Paths on Gangshan Hill,” “Tea-Seeking Amidst Cloudy Seas,” and “Hui Shui Embracing Elegance.” Moreover, we were the first to articulate the core principles for landscape creation—“ecological restoration, regional factors, landscape construction, and distinctive culture.” Throughout the design process, we explored the use of new plant varieties, innovated in plant combinations, and studied the application of diverse landscape features and elements. These efforts have played a crucial role in guiding the Duan Expressway’s landscaping and greening project toward greater ecological sustainability, human-centered design, and aesthetic appeal.

6. Innovative Solutions for Multiple Challenges in Mountainous Roadbeds: This project spans a long distance and involves numerous controlling factors, crossing various landform types. The terrain and geology along the route are highly complex, presenting a host of challenging roadbed treatment issues during surveying and design. These include: the application of prefabricated components in roadbed drainage and protection works; stability assessment and engineering support for large, complex accumulations of materials; construction of gravel roadbeds using highly water-saturated clay (or silt) soils; excavation and filling of expansive soil roadbeds; construction of high-fill roadbeds with thick overburden layers on steep slopes; utilization of abandoned railway embankments as high-fill roadbeds; stability analysis and protective measures for layered slopes composed of hard rock with weak interlayers; and green landscaping and erosion control for stone-filled embankments. Through technological innovation, we have successfully addressed a wide range of technical challenges related to roadbeds, achieving several original breakthroughs that have been subsequently applied and promoted in multiple follow-up projects.

Honored Achievements:

1. First Prize, Excellent Highway Design Award of the China Highway Survey and Design Association;

2. First Prize, Guizhou Province Outstanding Engineering Survey and Design Award;

3. First Prize, Guizhou Province Science and Technology Innovation Award for Civil and Architectural Engineering;

4. Obtained 15 patents and published 34 papers.

Project Showcase: