Stepping into the construction site of the Lize City Air Terminal integrated transport hub project (the Lize Business District Station on the northern extension of the New Airport Line), the sound of welding and machinery roars intertwine within the giant foundation pit, as over a thousand builders race against the schedule. The project's underground main structure is now nearing completion, with only a small amount of local structural work remaining on the north side. As the project advances, this integrated transport hub is accelerating from blueprint to reality.

Underground main structure enters final phase

The construction area is located in the northern part of the Lize Financial Business District. The huge foundation pit is rectangular, about 428 meters long and 154 meters wide, divided into east and west zones for simultaneous work, with a maximum depth of 36.3 meters. In the center of the pit, thick concrete piles have emerged above ground, and the layered construction marks on the side walls are clearly visible. Workers are carrying out secondary masonry and installing equipment such as air ducts and water pipes.

"At present, construction of the underground main structure is in its final stage, with a small amount of local structure on the north side being closed up," said He Yongyue, chief engineer of the project management department for the northern extension of the New Airport Line at Beijing Urban Construction Rail Transit Engineering Co., Ltd., pointing to the foundation pit.

The project has now fully shifted to equipment installation, secondary structural masonry and decoration. At that time, this "underground city" with a total building scale of about 307,000 square meters and an underground building area of about 287,000 square meters will move from the structural construction stage to the functional formation stage.
Innovative "skirt-edge cover-excavation top-down method" underpins deep foundation pit safety

The foundation pit is large and deep, surrounded by numerous high-rise buildings, adjacent to the busy Lize Road, and with the operating Metro Lines 14 and 16 passing "close by," so the construction difficulty is self-evident.

"Traditional support methods are hard to meet construction requirements, so the project innovatively adopts the 'skirt-edge cover-excavation top-down method' construction technique, using the top-down method to build the perimeter structure and relying on the perimeter structure to resist water and soil pressure, which can both prevent the risk of foundation pit collapse and improve construction efficiency," He Yongyue explained. At the same time, BIM digital technology is used throughout the project construction process to integrate all information on building structures, pipelines, mechanical and electrical systems, conduct pipeline collision detection, implement virtual installation, predict construction difficulties in advance, and achieve refined management throughout the process.

"The closer we get to the end, the more we must not slack off," said a relevant person in charge of the Fengtai District Housing and Urban-Rural Development Commission. Given the project's large scale and many hazardous works, the housing and construction department will take hazardous works as the focus of supervision, strengthen inspections of expert demonstration of special construction plans, on-site patrols and construction monitoring, and urge construction, building and supervision units to fulfill their main responsibilities to ensure safety is foolproof.

One-stop check-in and baggage drop-off, maximum transfer walk no more than 4 minutes

The entire hub adopts a three-dimensional "station-city integration" layout, with the five underground floors arranged by function according to travel flow.

Aviation service facilities are set up on the first and second underground floors. Here, passengers can not only handle regular check-in and baggage drop-off, but also enjoy the "early arrival" baggage drop-off service — they can drop off baggage here one day before the flight, travel light by rail to Daxing Airport on the day of departure, and the checked baggage will arrive at the airport on Daxing Airport Line trains according to flight times.
The second underground floor is the core transfer level, connecting the ordinary commuter metro station hall, the Daxing Airport Line station hall and the underground space of the Lize area on the same plane. The third underground floor mainly serves passengers arriving in Beijing. Passengers returning from Daxing Airport can transfer to the metro without security checks after leaving the station, and can also take taxis, ride-hailing cars and private cars nearby, achieving seamless connections; the fourth and fifth underground floors are planned as contiguous large parking garages, with passages interconnected with the underground garage in the northern part of the Lize Financial Business District, accommodating both daily parking in the area and airport pick-up and drop-off parking needs.
"From the very beginning of design, the project prioritized shortening transfer distances, with the farthest transfer walk among the five lines not exceeding 4 minutes," He Yongyue said. By organizing commuter flows, air passengers and surrounding office and commercial flows in layers and zones, the hub optimizes the layout of station halls, platforms, transfer passages and facilities such as escalators and elevators, comprehensively improving the transfer experience.
Five-line transfer gradually realized, underground connectivity reshapes the business district
In the initial stage of operation, the hub can realize three-line transfer among Metro Lines 14 and 16 and the Daxing Airport Line. Later, as Line 11 and the Lijin Line are completed and put into use, five-line transfer will be gradually realized, making it convenient for citizens to go to Daxing Airport. Relying on this hub, after the Lijin Line is completed in the long term, it will take 10 minutes by rail from here to Financial Street; after the hub is put into operation, it will take 24 minutes to reach Beijing Daxing International Airport directly.
The entire hub is located underground, connecting the station with office buildings, commercial facilities and urban roads through underground public spaces, transfer passages, entrances and exits, and connections with surrounding plots. "At that time, it will not only significantly enhance the comprehensive transport distribution capacity of the Lize Financial Business District and effectively shorten passengers' travel time, but also provide citizens with more convenient, efficient and comfortable travel services, helping Lize build an international financial business district," said a relevant person in charge of the Lize Financial Business District Management Committee. In the future, after operation, surrounding commuters will be able to enter office areas directly via rail transit, reducing detours on the ground; passengers and citizens will also be able to reach commercial and public service spaces more conveniently.
During the "15th Five-Year Plan" period, the Lize City Air Terminal, Lize MixC and industrial carriers will be delivered one after another, and the development value of the northern part of the Lize Financial Business District will be fully transformed from market expectations into real dividends.

People's Daily Online - Beijing Channel