The Beijing subway line 10 Guomao station is a large interchange station and to transfer with metro line 1. Its position is under the Guomao overpass, where the bridge piers and pipelines are extremely intensive. The surrounding environment is particularly sensitive. Therefore, the construction condition is very harsh. While the construction method designed by Sinorock placed second in the National Science and Technology Progress Award.
Engineering Geological Condition:
The engineering geological and hydrogeological conditions are terrifically complex in the construction site. The upper stagnant water is saturate above the structure. There are mainly medium-fine sands and silty-fine sands in the ministry of the arch, which will be affected by dynamic load obviously. The arching condition is very poor, the construction difficulty is great and the risk is too high.
Technology Innovations and New Technology Applications:
1. First put forward to adopt the design concept of separated island platform station in the dense regions of bridge pier. It divided the whole station into two parts which is designed between the two rows of bridge piers respectively. This design can not only achieve the construction demand but also without dismantling bridge piers. It doesn’t affect the normal operation of the overpass and it also brings great convenience of passenger traffic.
2. Implement the comprehensive and whole process of risk management. On the basis of dynamic diagnosis of overpass, it has been creatively proposed for the municipal bridge to use the controlling settlement concept of “classification, regional, grading,” and specific protection measures according to the health of the overpass.
3. The composite bolt pile protection technology was applied in the bridge pier with solid and isolation protection for the first time. Namely, the specialized long anchor bolt will be drilled downward the ground. Then, grouting the cement material from the bolt hole to solid soil around the bridge pier. Meanwhile, it can cut off the spread of the cavern deformation during the excavation process.
4. Dynamic design and information construction. During the construction, through the strict real-time monitoring and information feedback, the dynamic design was carried out. It also guided the construction measures and the adjustment and optimization of the construction technology. Therefore, it ensured the construction quality and safety.