Recently, a "blue box" was installed on the scaffolding at Huacheng Road Station of Qingdao Metro Line 9. This "black technology" is used to prevent the collapse of high formwork, and its monitoring accuracy far exceeds national standards.

Scaffolding equipped with a "blue box"

This "black technology" refers to the high formwork monitoring system. Under the guidance and assistance of the Qingdao Municipal Public Works Engineering Quality and Safety Supervision Station, Qingdao Metro Group applied this technology for the ** time in the construction of Line 9, at Huacheng Road Station. This monitoring system consists of a terminal controller, a comprehensive analyzer, wireless inclinometers, wireless displacement meters, wireless load sensors, wireless audible and visual alarms, and a cloud platform for real-time monitoring and management of high formwork. It can monitor subtle changes in the axial compression, displacement, and tilt of the high formwork system during concrete pouring. Through hardware devices and advanced artificial intelligence algorithms, a complete "health check report" of the target building can be generated in a short time. At the same time, it can display the status of the high formwork in real time, greatly improving inspection efficiency, and through audible and visual alarms and back-end monitoring, it can effectively prevent collapse accidents caused by excessive changes in the support system.

Simply put, it can perform remote "pulse-taking" on the health status of the formwork support. Staff open one of the measurement points on a laptop, and a 3D image of the foot formwork appears before their eyes. Dozens of different sensors inside and outside the scaffolding are conducting real-time monitoring of various data such as the horizontal displacement of the formwork support, axial force of the vertical poles, vertical displacement, tilt of the vertical poles, and foundation settlement. According to reports, it supports remote monitoring and cloud-based viewing. Staff can grasp on-site conditions in real time without going to the construction site, and monitoring data can be uploaded to the monitoring cloud platform in real time. Once parameters such as support axial force, formwork settlement, relative displacement, and tilt of the support system change due to instability of the top braces, failure of fasteners, or excessive pressure, this monitoring system will immediately notify relevant personnel through wireless audible and visual alarms, text messages, and phone calls. On-site workers can obtain danger information in the ** time, stop work, and quickly evacuate the site.

In the past, scaffolding inspections could only rely on on-site checks by staff, which took three to four hours per round, and the naked eye could only observe relatively large deformations. Now, with this system, the historical curves of each monitoring point can be viewed in the back end. By monitoring fluctuations in the curves, it is possible to determine whether the support has deformed and to provide early warning and immediate response to potential risks and abnormal conditions. In addition, through the monitoring data of the support monitoring system, the construction parameters of the scaffolding and formwork can be adjusted in a timely manner, enabling the formwork support to meet the construction standards for high-performance fair-faced concrete that is "non-deforming, non-settling, non-leaking, non-polluting, and non-flowing."