Building underpasses on the south and north sides of Taiyuan Railway Station will form a ring road network around the station. The Shuangta North Road will achieve straight-through underpass in front of the station... In the future, Yingze Street, Shuangta North Road, and the planned Yingze East Street in Taiyuan will be interconnected, improving the traffic network around the railway station and stimulating rapid economic development.
　　On the morning of December 16, as Wang Qisheng, commander of the Northwest Command of China Railway 14th Bureau Group Co., Ltd., issued the order: "Shield launching for the Taiyuan Yingze Street underpass railway station channel construction project!" the 2-meter-diameter shield machine "Jinlong" began tunnel excavation. Project manager Han Zhonghui introduced that the north and south tunnels share 4 shield machines, each tunnel is supported by 20 steel pipes forming a retaining structure, and the shield tunneling section is about 100 meters. The project will underpass 10 high-speed rail, passenger dedicated line and other tracks of Taiyuan Railway Station. The project department adopted the latest new pipe curtain method construction technology for railway station tunnel excavation, which is the first in the country.
　　Shield machine "Jinlong" launches
　　At 10 a.m., at the northeast corner of Taiyuan Railway Station, 10 meters underground, 20 circular holes with a diameter of 2 meters on the west wall formed a rectangle. "I announce the shield launching for the Taiyuan Yingze Street underpass railway station channel construction project!" As Wang Qisheng gave the order, a small shield machine began to move slowly forward at the circular hole in the lower right corner. "The Yingze Street underpass railway station project is one of the main channels for Taiyuan's eastward expansion. According to the design, Yingze Street is divided into up and down lines in front of Taiyuan Railway Station, passing under the station from the south and north ends respectively." said Li Teng, director of the engineering department of the project under China Railway 14th Bureau. The south underpass is 107.6 meters, and the north underpass is 102.5 meters. Each tunnel is 18.2 meters wide and 10.5 meters high. The road design grade is urban secondary road, with a recent planned speed of 30 km/h and four lanes in one direction.
　　How to ensure the normal operation of the railway station and the smooth launching of the shield machine? Li Teng introduced that the preliminary work mainly includes line relocation and reinforcement above the excavation. The relocation includes contact网 poles, three 10 kV power cables, communication, water supply, heating and other pipelines. In addition, the project department reinforced the track and installed 180 mm lock pipe sheds, etc.
　　The shield machine "Jinlong" is 6.8 meters long and 2 meters in diameter, belonging to small shield machines. "This shield machine is tailor-made according to the geological conditions and technical requirements of the Taiyuan underpass project. There are four in total. Two of them are open-type shield machines that can see the external working environment and are used for excavation in the section close to the railway tracks above, which can effectively ensure the safety of the project." said Li Teng.
　　New pipe curtain method ensures safe railway operation
　　Taiyuan Railway Station has a history of more than 100 years and is a special-class railway station, connecting the north and south Tongpu Line, Daxi Line, Shitai Line, Shitai Passenger Dedicated Line, Taijiao Line, Taizhongyin Line, Jingyuan Line, Jiexi Line, etc. It has 10 track lines including high-speed rail, ordinary fast, passenger dedicated, and heavy-haul freight trains. The average daily passenger volume is 133,000 person-times, and more than 140 trains depart to all parts of the country every day. It is the railway station with the highest personnel distribution volume in Shanxi Province. "The station has undergone 5 large-scale and more than 20 small-scale station renovations. There are more than 200 obstacles underground, including abandoned contact网 pole foundations over ten meters long, waste steel rails, sleepers, etc., and the geological conditions are complex." said Li Teng. In addition, the project needs to overcome many difficulties. For example, the closest distance between the top of the shield machine and the bottom of the sleepers is only 2.7 meters. With the frequent daily traffic of the railway station, the surface settlement during excavation needs to be controlled at 10 mm. To this end, the project department adopted the latest new pipe curtain method construction technology, first driving small pipes and then forming a large tunnel, to reduce construction risks and ensure safe railway operation.
　　During construction, multiple small shield machines are used in the two construction areas on the north and south of the railway station, each excavating 20 times from east to west. Each channel forms 20 steel pipe channels over 100 meters long, arranged in a rectangular shape. Then the steel pipes of the two channels are cut and welded respectively, and "threaded" to connect into two overall channels similar to a bracelet shape. "Using this construction technology for railway station tunnel excavation, achieving four-lane traffic in a single tunnel is the first in the country." Li Teng introduced. While the shield machine is excavating, the steel pipes are inserted simultaneously. The project uses fully automatic welding equipment and is expected to complete the main underpass channel project in August 2018.
　　A ring road network will form around the railway station
　　As an important gateway of Shanxi Province, Taiyuan Railway Station's surrounding municipal supporting projects are not perfect. At the same time, as one of the main urban arterial roads in Taiyuan, Yingze Street's east extension project has been put on the agenda with the city's development.
　　According to the plan, two new underpasses will be built on the south and north sides of Taiyuan Railway Station, each with four lanes in one direction. The north channel is east-to-west, and the south channel is west-to-east, forming a ring road network around the railway station.
　　The planned Shuangta North Road will be widened and reconstructed, with an underpass set up at the railway station section to achieve rapid north-south traffic. At the same time, Yingze East Street, Haojiagou Street, etc. are planned to be newly built.
　　After the roads are completed, Yingze Street, planned Yingze East Street, Jianshe Road, and Shuangta North Road around Taiyuan Railway Station will be interconnected, playing a very important role in improving the urban traffic network, facilitating public travel, and accelerating Taiyuan's economic development.