Six shield tunnel sections of chengdu metro line 17 have been completed

On the afternoon of June 30, the reporter learned from the second aviation bureau of CCCC of the central state-owned enterprise of China that on the afternoon of June 29, all the six shield tunnel sections of the first phase of chengdu metro line 17 project constructed by this unit were completed, and the trial operation is expected to be opened before the end of 2020.

According to wang zhangjun, general manager of CCCC's southwest regional headquarters, the first phase of chengdu metro line 17, which will connect wenjiang district with wuhou district, will be the second subway in southwest China with a speed of 140 km/h. It will be built by CCCC in PPP mode and the first subway line built by CCCC in sichuan province.

Construction of the 05 civil engineering project undertaken by the second aviation bureau of the People's Republic of China (CCCC), with a total tunneling length of more than 10 kilometers and a contract value of more than 1.8 billion yuan, started on February 27, 2017. This section passes through the "three high" complex geology of "high water abundance, high sand and pebble content and high bleaching stone strength", which is known as "drilling holes in flowing sand and stone piles". At the same time, it also runs through some major risk sources, such as chengxiapu railway, chengdu metro line 4, chengxiapu expressway, and important water supply pipes, which is very rare in China's subway construction.

The second shipping board of friends in chengdu urban construction company deputy general manager He Chenghai tells a reporter, a railway, average every 9 minutes a high-speed trains, shield crossing into railway place buried depth, outer edge and the elevated bridge pile foundation and tunnel clear distance are less than 7 meters, still need to pass through the dense pebble soil, the surface subsidence occurred easily in the process, the settlement requires "millimeter", construction of difficult, high risk, beyond imagination.

For this purpose, the company of chengdu metro engineering construction unit and construction units in the second shipping board of alternating strengthen technology research, in addition to the technical measures, also formed the underground excavating in all aspects of vertical system, and adopt advanced automated monitoring system for real-time guiding drivage, final victory through multiple special major risk source, realize all six sets of shield tunnel, and set the country's first large diameter shield sandy pebble in the water areas through successful operation of high-speed railway precedent.

After completion of the first phase of chengdu metro line 17, it will extend to dujiangyan in the west and to tianfu international airport in the southeast via shuangliu airport, forming a fast backbone transportation line from dujiangyan, wenjiang, shuangliu airport and tianfu new district to chengdu tianfu international airport. With the completion of line 17, the distance from wenjiang district and shuangliu district to tianfu new district will be reduced to less than 20 minutes for more than 1.6 million people.

This is just one of nine urban rail transit projects under construction in chengdu. Since 1969, Beijing became the first city in China to have a subway. By the end of 2018, the total length of urban track in mainland China (excluding Hong Kong, Macao and Taiwan) had reached 5,761 km.

At present, in has opened 35 cities in urban rail transit, the operating range of 17 cities of more than 100 kilometers, 784.6 kilometers of Shanghai, Beijing, 713 kilometers, guangzhou operation line length of more than 400 kilometers, nanjing, wuhan, chengdu, chongqing, line length of more than 300 kilometers, shenzhen, tianjin two city line length of more than 200 kilometers.

By the end of 2018, the total investment in the 44 planned routes approved by the national development and reform commission reached 38911 billion yuan. The investment plans of Shanghai, Beijing, guangzhou, hangzhou, shenzhen and wuhan all exceed 200 billion yuan. The total investment of the planned routes in chengdu, chongqing, Qingdao, tianjin, xi 'an, suzhou, fuzhou, xiamen and changsha is all above 100 billion yuan. The total investment of urban rail transit plan has been steadily increasing, and the scale of urban rail transit lines has been continuously expanding and gradually forming a network. The development of urban rail transit has gradually entered the era of network development from a single line.

With the rapid development of rail transit, a large number of construction enterprises have grown up rapidly. In recent years, only the second aviation bureau of CCCC has participated in the construction of 29 subway projects, among which 13 are currently under construction, with the total contract value of projects under construction exceeding 10 billion yuan.