Tunnel construction started on 1958 and stopped in March for some reason.

1974 10 resumed work, and the original railway soldiers undertook the construction.

When I opened the 13 closed cave, I saw that the cave was full of water, the vault collapsed, the side wall collapsed, and there was a lot of waste.

The officers and men overcame difficulties and obstacles for a year and a half, cleared up nearly 50 thousand cubic meters of debris, and then began to excavate the upper pilot tunnel.

65438+June 65438+June 0977, the main project was completed, and the track was laid and the tunnel was crossed in August 65438+May of the same year.

After the opening of 1978 tunnel, it was found that the whole ballast bed was cracked and bulged. In less than two years, the ballast bed rose to 300 mm, and the ditch broke, the side wall fell off and deformed, the vault cracked, and the local side wall invaded, threatening traffic safety.

1May, 1983, after the disease was rectified, at the end of 1984, it was found that the whole ballast bed in the area where the inverted arch was not replaced was cracked one after another, and the horizontal error between the two rail surfaces reached 60 mm, and some diseases such as vault falling off, side wall cracking and loose foot falling off were found.

Through investigation and demonstration in many ways, it is found that the uplift of ballast bed is due to the fact that the stratum at the bottom of tunnel contains a large number of chlorite and montmorillonite that swell when it meets water.

Therefore, starting from 1990, the integral ballast bed of Mu Shang section was demolished, reinforced concrete inverted arch was added, and sleeper slab was laid.

At the same time, some side walls are demolished, and grouting reinforcement is carried out again after lining. Some side wall vaults are reinforced by hanging nets with small bolts and shotcrete.

In order to eradicate the frost damage of the subgrade at both ends of the tunnel, the subgrade soil below the cutting bed at the entrance and exit section was completely replaced, and a cold-proof and heat-insulating drainage ditch was added.

The construction of Guanjiao Tunnel lasted for more than 30 years, except for the shutdown in 13 years, the formal excavation lasted for five and a half years, and the disease treatment lasted for more than nine years. It can be seen that the tunnel has complex geological structure, harsh climatic conditions and serious diseases.

Xinguanjiao Tunnel, as the control project of Xige (Xining-Golmud) Railway Second Line Project, was fully started on June 6, 2007. Construction by drilling and blasting method, with a total length of 32.645 kilometers, was designed by China Railway First Survey and Design Institute Group. Xinguanjiao Tunnel is designed as two parallel single-track tunnels with a design speed of 160 km/h. A total of 10 inclined shaft (a total of 15.253km) and 9.8 km parallel pilot tunnel are located in a straight line, with a total construction period of 5 years.

By April 20 14, the excavation of the tunnel entrance and exit section (construction by China Railway Tunnel Bureau) had been completed, and the integral ballast bed was under construction.

After the completion of Guanjiao Tunnel, the existing line will be shortened by 36.837 kilometers.

Guanjiao Tunnel Construction Bid Section of the second line project of Xining-Golmud section of Qinghai-Tibet Railway is located in the section from the ceiling of the existing Qinghai-Tibet Railway to Chahannuo Station. The newly-built Tianjun station crosses Buha River and Lumengqu Mountain in front of Nanshan Mountain in Qinghai, and then crosses Nanshan Mountain in Qinghai with a tunnel of 32.605km (the elevation of tunnel entrance rail surface is 3380.75, and the elevation of tunnel exit rail surface is 3324.05), and the Yankendelong ditch is connected with Chahannuo.

This section of the line is straightened at one time, with an interval length of 39.084 kilometers. The existing Guanjiao Tunnel was abandoned, and the new Guanjiao Tunnel was built into two parallel single-line tunnels.

The mileage at the entrance end of the tunnel is DK280+570, and the mileage at the exit end is DK3 13+ 195.

Scale: The total length of the tunnel is 32.605km/ seat (double-line separated straight tunnel).

Design unit: China Railway No.1 Survey and Design Institute Group

Construction unit: China Railway Tunnel Bureau and China Railway 16th Bureau.

Design speed:160km/h

Effective clearance area of tunnel: 42.04m2

Time limit for a project: June 6, 2007 +065438+ full commencement, and the completion time limit is adjusted to June 2065438 +04+February 2065438+0.

Construction method: drilling and blasting construction, a total of 10 inclined shaft (a total of 15.32 1km), 9.8km parallel pilot tunnel to assist the main tunnel excavation. In September, 1965, 438+065,438+0 was the entrance of Guanjiao Tunnel, the longest tunnel with high altitude in the world.

On 201210 June 18, China Railway Corporation (formerly the Ministry of Railways) decided that the China Railway Tunnel Bureau would reinforce the No.6 inclined shaft.

2065438+On April 8th, 2003, No.8 and No.7 inclined shafts were connected with the second line.

201165438+1October 2 1, No.7 inclined shaft and No.6 inclined shaft of Line 1 run through, and China Railway Tunnel Bureau completed the reinforcement task.

1April15th16th, with two gunshots in the depth of Guanjiao Mountain on the northeast edge of Qinghai-Tibet Plateau, the main tunnel of Xinguanjiaoshan Tunnel on Qinghai-Tibet Railway, the world's longest plateau railway tunnel, which was jointly fought by China Railway Tunnel Group and China Railway Construction 16th Bureau Group for nearly seven years, ran through the whole line.

Guanjiao Tunnel, with a total length of 32.645 kilometers, is a control project of the second double-track project of the West (Ning)-Golmud Railway of Qinghai-Tibet Railway. The 16th Bureau Group undertook the construction of17.372km entrance section, and China Railway Tunnel Bureau undertook the construction of15.273km exit section.

The engineering and hydrogeology of this pipeline section are extremely complicated. There are not only continuous sand layers, long karst sections and faults here, but also the underground water inflow is extremely rare. The maximum daily inflow of the whole pipe section can reach 320,000 cubic meters.

Guanjiao Tunnel is divided into 10 inclined shaft (7- 10 inclined shaft constructed by China Railway Tunnel Bureau, 1-6 inclined shaft constructed by China Railway Construction Bureau) and main tunnel operation area constructed by China Railway Construction Bureau (China Railway Construction Bureau 16).

The longest inclined shaft is 2808m, and the rest inclined shafts are all above1000m, with an average slope of 1 1%.

At present, this long-distance and large-volume continuous reverse slope tunnel construction drainage technology is the first case at home and abroad.

The builders set up a double arch fixed pumping station every 300 meters in the inclined shaft, and the two chambers are connected with each other. One cavern is used as a sedimentation tank, and the other cavern is equipped with a high-power inlet pump after comparison and selection to realize relay drainage, which once set a new record for the construction of plateau railway tunnels in China with a daily displacement of inclined shafts of more than 6.5438+0.7 million cubic meters.

At the same time, the builders flexibly used curtain grouting, radial grouting, top water grouting and other construction technologies, and adopted materials such as Malisan, polymer materials (HCH-I polymer water gel consolidation materials, inorganic plugging materials with a span of 2000 HCH-III, and emergency rescue materials with a span of 2000), cement slurry, water glass, calcium chloride and so on. , reasonably control the setting time of slurry, strictly control the grouting range, and ensure grouting.

There is a 550-meter aeolian sand section at the entrance of the main tunnel of Guanjiao Tunnel, with a covering layer of 2-23 meters. This long-distance continuous shallow-buried aeolian sand section is the first time in China.

On the basis of previous short-distance sand layer construction experience, the builders adopted the scheme of five steps+expanding arch foot and temporary cross brace after continuous construction practice and exploration, and laid the screen with the aperture of 1.5 mm immediately after excavation to prevent aeolian sand from slipping in poor water areas; The advanced support adopts pipe shed+conduit grouting support, and the safe spacing is strictly controlled.

After more than one year's construction, the construction of aeolian sand layer in 550-meter-long poor water area of Zhengdong I and II lines has been completed safely and with high quality.

The exit section passes through 10 fault zones with different sizes and a syncline, among which Erlangdong fault zone (F3) is the most developed, which is a first-class regional deep fault, and there is the possibility of moderate and strong earthquakes in the future, and the fault bundle around it is 2355m long.

The rest are secondary regional faults and * * * faults (F), and the surrounding rock above Grade IV in the exit section accounts for 77.438+05%.

The single-head excavation of No.7 inclined shaft is 4620 meters long.

2065438+On March 20th, 2004, the No.4 and No.5 inclined shafts of Guanjiao Tunnel, a control project of Xige Second Line of Qinghai-Tibet Railway, which was undertaken by a company of China Railway 16th Bureau Group, achieved zero error penetration.

At this point, the world's first high-altitude railway, Long Tunnel Line 2, which was built by China Railway Tunnel Bureau and China Railway Construction 16th Bureau, was completed.

The No.4 inclined shaft of Guanjiao Tunnel is located in a water-rich area, with an average elevation of more than 3,600 meters and a daily drainage of more than 50,000 cubic meters. During the construction, in order to reduce the drainage pressure of the inclined shaft, improve the working environment in the tunnel and reduce the construction risk, the project department adhered to the principle of "blocking first and then discharging", and carried out curtain grouting of 675 meters and radial grouting of 150 meters. Malishan was used in some sections.

After six years of hard work, the tunnel construction safely passed through the weak surrounding rock and water-rich area, and the second line was completed on the 20th, realizing natural drainage, which won time for the next integral ballast bed construction and laid a solid foundation for the smooth opening to traffic at the end of the year.

Xinguanjiao Tunnel runs through the whole line.

According to the news of the Central Broadcasting Network, on April 6, 20 14, after the completion of the Xinguanjiao Tunnel on the Qinghai-Tibet Railway, employees of the 16th Bureau of China Railway Construction celebrated.

On the same day 16: 00, with the sound of two gunshots in the depths of Guanjiao Mountain on the northeast edge of Qinghai-Tibet Plateau, China Railway Tunnel Group and China Railway Construction 16th Bureau Group jointly fought for the world's longest plateau railway tunnel in the past seven years-Xinguanjiao Tunnel on Qinghai-Tibet Railway.

"Guanjiao" means "ladder to heaven" in Tibetan.

Xinguanjiao Tunnel is the control project of the second double line of Qinghai-Tibet Railway, with the highest elevation of 3497.45 meters and the total length of 32.645 kilometers.

The tunnel is located in Guanjiao Mountain in Tianjun County and Wulan County of Qinghai Province, between Tian Peng Station and Chahannuo Station of Qinghai-Tibet Railway, with a design speed of160km/h.

After the official operation, the train crossing Guanjiao Mountain will be shortened from the current 2 hours to 20 minutes.