New progress has been made in the construction of Beijing's "Underground East Sixth Ring Road." Recently, the main structure construction of the 1.8-kilometer open-cut section has been fully completed. Currently, the mechanical and electrical works of the East Sixth Ring Road reconstruction project are carrying out fire protection pipeline installation and strong-current bracket installation in the lower chamber, as well as tunnel interior decoration construction and decorative panel installation, striving at full speed toward the goal of full-line opening to traffic.

The East Sixth Ring Road reconstruction project starts from the Jingha Expressway in the south and extends to Luyuan North Street in the north, with a total length of approximately 16.3 kilometers. The road is classified as an expressway, with dual carriageways of three lanes each and a design speed of 80 km/h.

Open-cut section of the East Sixth Ring Road reconstruction project, where construction workers are installing ancillary facilities

According to reports, tunnel construction is divided into the shield-driven section and the open-cut section. On August 21, 2023, the approximately 7.4-kilometer shield-driven section achieved dual-line breakthrough. At the construction site of the East Sixth Ring Road reconstruction project, the reporter observed that the main structure construction of the 1.8-kilometer open-cut section has been fully completed. At the north portal of the tunnel, a wide and smooth road extends southward in each direction, seamlessly connecting with the shield-driven tunnel section. The tunnel's mechanical and electrical systems have entered the comprehensive construction phase.

Shield-driven tunnel of the East Sixth Ring Road reconstruction project, where construction workers are installing facilities

In the shield-driven tunnel section, the installation of jet fans and lighting fixtures has been completed, and fire protection facilities including fire hydrants, water spray valve group boxes, and pipelines have been fully installed. Pipeline pressure testing is now underway. Next, mechanical and electrical facility installation will be carried out in the open-cut section, shield shafts, and management areas.

Fatigue-alert lighting facilities installed inside the tunnel

It is worth noting that the mechanical and electrical systems of the East Sixth Ring Road tunnel have been intelligently upgraded on the basis of the original design specifications. Millimeter-wave radar has been added, and combined with full-coverage video in the tunnel, it enables full-line dynamic tracking of vehicles inside the tunnel. Through tunnel broadcasting, information display screens, and directional signage, vehicles are guided to drive safely. Four fatigue-alert lighting facilities have also been installed in the tunnel to help alert drivers and ensure driving safety.

To implement the "dual carbon" concept, the project adhered to ecological route selection during the planning and design stage, making full use of surface space by going underground through the city. The long shield-driven construction scheme was adopted to minimize environmental impact, saving approximately 600 mu of land and reducing tree felling and transplantation by about 47,000 trees.

The East Sixth Ring Road reconstruction project adopts intelligent tunnel ventilation technology, conducting real-time monitoring based on the average vehicle speed, traffic wind speed, and distribution of pollutant concentrations such as carbon monoxide inside the tunnel to achieve energy-efficient ventilation. Air purification devices have been installed at the south and north shield shafts of the tunnel, which can minimize the impact on surface landscapes, with an expected purification efficiency of over 80%. Two new types of noise-reducing pavement structures are also adopted, which can reduce rain-related accident rates by more than 40% while lowering roadside traffic noise by 2-3 decibels.

To improve road safety performance and address the difficulty of traditional road markings in balancing reflectivity and skid resistance, a full-life-cycle durable anti-skid hot-melt marking coating was developed over three years and has been continuously iterated and upgraded. According to reports, this marking coating is being applied for the first time in the formal engineering design of a Beijing expressway. Tests have shown that compared with traditional road markings, the new coating increases marking brightness by 30% and skid resistance by 60%.

After the civil engineering and mechanical and electrical works of the East Sixth Ring Road reconstruction are completed, landscaping works will commence, covering a total area of 472,600 square meters, mainly including tree and shrub planting, slope hydroseeding, and ground cover planting. The landscaping works will deepen integration with the surrounding environment to create an ecological and beautiful "natural landscape avenue." In selecting plants for landscaping, native species will be prioritized, with Chinese pine, Chinese ash, smoke tree, and Sabina vulgaris preferred for their strong resistance, cold tolerance, and drought tolerance. At the same time, attention will be paid to seasonal color changes to form a sustained and effective stable landscape. In addition, full consideration will be given to driving sight distance and anti-glare requirements, highlighting the characteristics of contiguous patches and sections to achieve a combination of protection and aesthetics.

The Beijing East Sixth Ring Road (Jingha Expressway - Luyuan North Street) reconstruction project is a municipal key project implementing the "Beijing Urban Master Plan" and the "Regulatory Detailed Plan for Beijing Municipal Administrative Center." After opening to traffic, it will promote the integration of Tongzhou urban area with the administrative office area of the municipal administrative center, and is of great significance for improving Beijing's traffic service level, building a comprehensive transportation system, and promoting regional transportation integration in the Beijing-Tianjin-Hebei region.