The country's first sliding air ribbed foundation pit air membrane is put into use

Recently, the construction site of Jinan Rail Transit Line 7 ushered in a remarkable innovative achievement - the country's first sliding air ribbed foundation pit air membrane was officially built and put into use. The successful application of this technology has brought new changes to the construction of subway projects, marking an important step in dust prevention, noise reduction, intelligence and efficiency in construction.

As a new green technology, foundation pit air membrane technology has gradually emerged in the construction field in recent years. At present, air membranes mainly include three types: air-bearing type, airbag type (air pillow type), and air rib type. The sliding air ribbed foundation pit air membrane used by Jinan Rail Transit Line 7 is the first in the country and the first application of foundation pit air membrane in subway projects.

The air membrane is installed in the semi-covered excavation section of Longao Building Station. The foundation pit is 59 meters long and 11 meters wide, with a maximum depth of 28.8 meters. Based on the limited construction work surface, the air membrane is designed into three parts, the middle part is about 22.5 meters long and 2.9 meters high; the two side parts are 12.5 meters long and 3.9 meters high. Tracks are installed under each air membrane, which can be moved in plane according to the needs of on-site construction, so as to achieve full coverage of the subway station foundation pit and support the green dome for dust suppression and noise reduction for the construction site.

Compared with the traditional fixed canopy, the air rib foundation pit air membrane has significant advantages. It uses the membrane cloth air rib to pressurize to form a "hollow self-stabilizing structure", realize the "double-layer membrane cloth + air interlayer" dust and noise reduction, and significantly improve the safety, stability, dust and noise reduction effect. At the same time, the overall installation and disassembly are convenient and fast. From factory processing to on-site assembly, the entire construction process takes less than 1 month, and it only takes 1 day from on-site installation of the air membrane to commissioning. In addition, the air film can be opened or closed by sliding on the track, and can be opened and closed automatically according to the construction needs to achieve free movement. Under the premise of controlling dust and reducing noise, it effectively guarantees the hoisting operation during the construction period, which is especially suitable for linear engineering construction scenes such as subways. The use of new membrane materials also enables it to be recycled repeatedly, and the comprehensive cost is optimized by about 30% compared with traditional canopies.

With the continuous development and innovation of inflatable air film structure technology, it is believed that it will be applied in more complex engineering scenes in the future, providing more possibilities for the green development of the construction industry.