Recently, Segment T55 of the Shiziyang Bridge under the Shiziyang Link project, a core transportation hub in the Guangdong-Hong Kong-Macao Greater Bay Area, was successfully hoisted into place, with the height of the main tower surpassing the 300-m milestone. According to reports, the Shiziyang Link project is another super cross-river mega project in the Greater Bay Area, following the Hong Kong-Zhuhai-Macao Bridge, the Shenzhen-Zhongshan Link, and the Nansha Bridge.

The Civil Works Section 16 Project Department of China Railway First Group Co., Ltd. for the Shiziyang Link project (hereinafter referred to as the Shiziyang Project Department), is responsible for the prefabrication of all box girders for the offline civil works Sections 11 and 12 of the Shiziyang Link Project, covering a total length of 7.4 km.

To build a “mega project”, quality must come first. Led by Deputy Project Manager Song Xiong, the technical team repeatedly adjusted various aspects such as form design, testing and inspection, and data optimization in accordance with the box girder’s external dimensions, and developed an innovative flexible end formwork hydraulic installation and removal device.

By locking four points on the end formwork and activating the hydraulic system, the device enables the end formwork to be withdrawn in a parallel motion as a whole, reducing concrete damage at the girder end and improving stripping efficiency. It also allows one-click installation and removal of end formwork at different angles, enhancing productivity and improving protection of finished components.

“This device addresses the drawbacks of traditional end formwork, which is difficult to install manually and can easily cause damage to the girder-end concrete during stripping, thereby affecting girder quality,” said Song Xiong.

The physical quality of expressway box girders is equally critical. The project team also invented an energy-saving steam curing system that combines photovoltaic energy storage with grid power. It ensures uniform steam coverage inside the curing chamber, improves the steam curing effect, and resolves issues such as surface color variation caused by spray curing.

Empowered by these technological innovations, the box girders produced by the Shiziyang Project Department feature a consistent glossy appearance with a mirror-like finish. The pass rate has reached 99.6%, placing it at an advanced level within the industry.