Recently, it was learned from Wuqing District that the country's first culvert project crossing an operational high-speed railway—the Cuicheng Road underpass project beneath the Beijing-Tianjin Intercity Railway and the Beijing-Shanghai Railway—has been completed and is set to open to traffic. This project has accumulated experience for underpass projects beneath operational high-speed railways in China and plays an important role in travel near the Wuqing Station of the Beijing-Tianjin Intercity Railway.

  According to the head of the Wuqing District Construction Commission, the Cuicheng Road underpass culvert project mainly consists of five parts: a water conveyance box culvert for the First Branch Canal, road U-shaped grooves, box culvert jacking, the road, and a drainage pump station for the interchange. The project starts from Qianjin Road in the north, ends at Wei'er Road in the south, passes beneath the two railway lines of the Beijing-Tianjin Intercity Railway and the Beijing-Shanghai Railway, and terminates on the south side of the railways. It has a total length of 484 meters, a road width of 36 to 39.4 meters, and dual carriageways with six lanes. The bridge body weighs 9,113 tons, the designed maximum jacking force is 9,932 tons, and the total investment is approximately 150 million yuan. It is the country's first culvert project crossing an operational high-speed railway.

　Since construction began in April 2012, all participating personnel have overcome difficulties such as a narrow construction site, high groundwater levels, low foundation bearing capacity, the heavy weight of the bridge body, high requirements for settlement, the high operating speed of the Beijing-Tianjin Intercity Railway, and the high traffic density of the Beijing-Shanghai Railway along with high construction precision requirements.

　During construction, because the Beijing-Tianjin Intercity Railway and the Beijing-Shanghai Railway are only more than 20 meters apart and the groundwater level is very high, in order to prevent settlement of the Beijing-Tianjin Intercity Railway subgrade, the railway authorities required that uneven settlement during construction be strictly controlled within 1 millimeter. After thorough research and demonstration, the Construction Commission decided to set up two waterproof curtains between the Beijing-Tianjin Intercity Railway and the Beijing-Shanghai Railway. One consists of three rows of jet grouting piles, and the other consists of two rows of waterproof curtains.

　At the same time, the "skip driving" method was adopted for the construction of the high-pressure jet grouting pile waterproof curtains between the Beijing-Tianjin Intercity Railway and the Beijing-Shanghai Railway to reduce the impact of construction on the Beijing-Tianjin Intercity Railway subgrade. Jet grouting piles were used to fill the gaps between the retaining piles and the back piles of the jacking foundation pit, better ensuring the waterproof effect around the foundation pit. During the bottom sealing of the jacking working pit and the construction of the waterproof curtain jet grouting piles, the ground from 6 to 8 meters below the surface is a silty soil layer. Through the repeated spraying method, the quality of the jet grouting piles was improved, and the effect of foundation pit bottom sealing and waterproofing was enhanced, filling a gap in waterproofing for underpass tunnels beneath operational railways in China.