By the end of 2017, the mileage of high-speed railways in our country has reached 25,000 kilometers and ranked first in the world. The four-longitudinal and four-lateral high-speed rail network is also perfect. However, there are still many miracles for infrastructure madness.
According to the Science and Technology Daily, on January 16, the only high-risk high-speed rail tunnel in the world's alpine region and the high-speed railway Aimin Tunnel in Harbin (Erbin) (Danjiang) went through completely, marking the completion of the Harbin-Muzhou high-speed line project.
It is understood that, Aimin Tunnel is located at 44.6 degrees north latitude Mudanjiang City, a total length of 2940 meters, located in the alpine region of China, the extreme minimum temperature of -35 ℃, 'V' shaped elevation 41.8 meters, slope gradient of 14.8 ‰, 18 ‰, far beyond Ordinary high-speed rail 5 ‰ slope.
At the same time, the tunnel traverses a number of strata such as "loose sedimentary beds" and "tertiary sediments" across the board. The fifth and sixth grades occupy 95% of the total length of the tunnel and are called the "Geological Museum of High and Cold Regions."
In particular, more than 470 meters of sandstone and mudstone interlayered sections such as tunnel entrance to No. 1 inclined well, No. 1 inclined shaft to No. 2 inclined shaft interval are weak in geology and even occur mountain creep, resulting in serious collapse of the tunnel arch settlement and continuous collapse, Several times on-site construction had to stop.
In order to overcome the -35 ℃ ultra-low temperature rise, V-shaped 42 seconds out of two major challenges quickly, China Railway Construction Bureau 22 to the tunnel inlet section of the creep geology took 'Anti-slide pile protection + surface grouting' And other measures, as in the tofu block implanted 'steel bar', improve soil self-stability, to ensure safe driving.
Harm high-speed rail (Harbin-Hong Passenger Dedicated Line) is China's "medium-and long-term railway network planning," one of the major construction projects, is China's 'eight vertical and eight horizontal' high-speed rail network in the most northern 'a horizontal' , Which is also an extension of Harbin-Dalian high-speed rail to the southeastern region of Heilongjiang Province. It is very important for the construction of the Eurasian Continental Bridge.
The total length of 292.995 kilometers leads from Harbin to east via Acheng and Mao'ershan to Shangzhi, and then southeast to Wanshan, Weihe River, Yabuli, Hengdaohezi, Hailin to the terminal Mudanjiang, and the designed speed is 250 kilometers per hour , It is estimated that it will open to traffic by the end of 2018. The journey time from Harbin to Mudanjiang is estimated to be only 1 hour, and Harbin to Suifenhe only 2 hours.
