Yakang Expressway, referred to as Yakang Expressway for short: connecting Chengya Expressway, starting from Caoba Town, Yucheng District, Ya 'an City, passing through tianquan county and Luding County in the west, and ending in the east of kangding city (vegetable garden in Kangding County). The total length of the route is about 135 kilometers (including 89 kilometers in Ya 'an section and 46 kilometers in Ganzi section), with a design speed of 80 kilometers per hour, four lanes and a roadbed width of 20. The height difference of the whole line reaches1900m.
After completion, Chengdu can fly to Kangding in nearly 4 hours, saving at least 2 hours.
The bridge-tunnel ratio of the project is as high as 82%, which is one of the highways with the highest bridge-tunnel ratio and the most difficult construction in the province and even the whole country.
brief introduction
Yakang Expressway, referred to as Yakang Expressway for short: connected with Chengya Expressway, starts from Caoba Town, Yucheng District, Ya 'an City, passes through tianquan county and Luding County in the west, and ends in the east of kangding city (the vegetable garden in Kangding County).
It is an expressway from Ya 'an to Kangding in western Sichuan, a section of the national expressway network from Ya 'an to Yecheng in Xinjiang (G42 18), a section of the Sichuan-Tibet expressway, and an important part of Kangding to Luzhou, one of the five east-west directions in the "16 5.5" plan of the Sichuan expressway network.
At the same time, it is also a section from Ya 'an to Yecheng Expressway in Xinjiang, a section of Sichuan-Tibet Expressway. The route starts from Caoba Town, Ya 'an City, connects with the completed Chengya Expressway, passes through tianquan county and Luding County, and ends at the vegetable garden in Kangding County. The total length of the route is about 135km (including: Ya 'an section 89km, Ganzi section 46km and Ganzi section 55km), the design speed is 80km/h, the subgrade width is 24.5m, and the estimated investment is about 22 billion yuan.
meaning
Yakang Expressway is of great significance to the improvement of road traffic network structure in Ya 'an and even the whole western region.
Yakang Expressway is a section of the national expressway network from Ya 'an to Yecheng (G42 18), and it is a fast-track for China Unicom, Kangzang and Tibet. Upon completion, the highway network in western Sichuan will be improved, highlighting Ya 'an's location advantage in the transportation hub in western Sichuan. At that time, visitors can first appreciate the distant charm of the birthplace of tea culture in Ya 'an, and then drive to Kangding by Yakang Expressway for more than 2 hours to see Kangba culture.
Engineering situation
Gao Qiao tunnel ratio
The construction of Yakang Expressway faces a series of major technical and economic challenges such as safety, economy, ecology and convenience. Erlangshan extra-long tunnel, a controlled project, is 13.4 km long, ranking second among the expressway tunnels under construction in China. The main span of Kangxing Bridge on Dadu River in Luding is 1 100 meters, ranking first among similar bridges in the province. It is extremely difficult to construct a 50-kilometer-long tunnel group crossing the alpine valley.
The bridge-tunnel ratio of the project is as high as 82%, which is one of the highways with the highest bridge-tunnel ratio and the most difficult construction in the province and even the whole country. The height difference of the whole line reaches1900m.
Five major challenges
project construction
Facing the severe challenge of "five extremes"
The terrain conditions are extremely complicated. The project is located in the transition section from Sichuan Basin to Qinghai-Tibet Plateau, with rapid elevation climb, complex and diverse landform types, narrow and steep terrain, criss-crossing gullies, huge ups and downs, limited route layout and great difficulty in demolition and resettlement.
The geological conditions are extremely complicated. Crossing Longmenshan fault zone, the earthquake intensity is high, Erlangshan extra-long tunnel crosses 13 fault zone, and Kangding Kangxing Bridge on Dadu River in Luding is located in Y-shaped active fault zone, with unfavorable geological development such as landslide, debris flow and collapse.
The weather conditions are extremely bad. Across different vertical distribution zones of climate, severe weather such as rain, snow, ice, fog and wind on high-altitude sections has a long impact.
The ecological environment is extremely fragile. Crossing the giant panda habitat nature reserve and the rare fish reserve, there are many environmental sensitive points, and the task of environmental protection and soil and water conservation in the project construction is arduous.
Engineering construction is extremely difficult. This project has interfered with G3 18 lines and hydropower facilities for many times, with great safety risks. The 50-kilometer-long tunnel group passes through high mountains and canyons, and the construction access road is laid on cliffs, especially in Lu Kang section. The vertical elevation difference between the tunnel and G3 18 line is about 580m. In some contract sections, it is necessary to build a construction access road of about 8 kilometers on the steep slope of the canyon to reach the tunnel branch operation point. If the service road can't be paved, it is necessary to open a tunnel branch hole close to 1000 meters to reach the main line of the tunnel. Several large construction units located in the contract section of C 16-C 18 in Luding and Kangding took 1.5 years to open the construction access road and the construction branch tunnel, and finally started the main tunnel construction in 20 16 years. The Kangxing Bridge on Dadu River has a span of 1 100 meters, ranking first in the province, facing extremely high earthquake intensity (octave), complex wind field conditions, extremely unstable high and steep slopes, etc. Erlangshan Extra-long Tunnel has a total length of 13.4 km, the maximum buried depth of 1700 m, high geostress, easy rock burst and large deformation, and bad geology such as gas, karst and water inrush when crossing the 13 earthquake fault zone, which has great construction quality and safety risks. The single hole of inclined shaft is 3.3 km long, and the single-head tunneling of tunnel is 6.8 km long, so the construction scale of inclined shaft is high.
tighten up the management
Engineering construction is progressing in an orderly manner.
Facing the severe challenge of "Five Extremes", Yakang Company organized all parties involved in the construction to seriously implement the "Five Extremes" management of the modern project of the Ministry of Transport, and Qi Xin made concerted efforts to overcome difficulties and ensure the orderly progress of the project.
The construction of land requisition, demolition and relocation will be promoted in harmony. The project company takes the initiative to report actively, and uses multi-party joint meetings to solve the matching problem between the project progress and the land acquisition and demolition progress, so as to ensure the timely provision of the project construction land; On-site office meeting to legally and reasonably solve the problem of waterway water system and ensure the production and living needs of the people along the line; Thematic coordination meeting to solve major special problems; Design a return visit meeting to legally and reasonably solve local reasonable demands and related problems such as highway culture, ecology, environmental protection and water saving.
Promote project construction in a balanced way. Adhere to the "four tables" system such as annual progress plan, monthly work schedule, daily completion statistics and last month's work schedule statistics to ensure the dynamic control of project construction progress; Adhere to the "four centralization" such as centralized processing of steel bars, centralized and graded stacking of raw materials, centralized mixing of concrete and centralized prefabrication of beams and slabs to ensure that the source and process of engineering construction quality are controlled; Adhere to the operation of professional monitoring, special meetings, expert consultation, special expenses and other "four special mechanisms" to ensure the safety and stability of engineering construction.
The above is the introduction of CBI Zhong Da Consulting to Yakang Expressway. For more information about expressways, please pay attention to the architectural knowledge column of Zhong Da Consulting.
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