In order to break through the restrictions of confined space environment in tunnel works to implement innovative technologies, the construction team introduced a site-specific 5G base station. With the advantages of 5G network including low latency, high-speed transmission, and high device capacity, together with the development and implementation of various innovative technologies, we can improve the efficiency of project management, construction safety and site progress monitoring. We can also accumulate large amount of valuable data for the future development of cavern projects in Hong Kong.

Our site is located in Ma On Shan, where the aircraft satellite channel passes through, making 3.5GHz spectrum forbidden in this area. However, 3.5GHz is a common spectrum for 5G network. Therefore, we chose 4.9GHz spectrum to create a unique 5G network in Ma On Shan. Thanks to this site-specific 5G network, the construction team can use the digitalized systems freely without the restriction of location and network speed, e.g. the DWSS system, Measure-While-Drilling system even 200m length inside tunnel, RFID system, electronic document management system, 3D Scanning, etc. It allows site staff to send and receive large amount of real time construction information at different locations, strengthens connections, avoids complicated paperwork, and achieves the goal of paperless office.

The blasting process monitoring app, originally developed by the construction team, helps collect real-time data of the blasting process for comparison and analysis, so as to optimize each process. When combined with the application of BIM, 5G network can help strengthen the performance of BIM, improve the constructability of construction projects, and save time and costs. Engineers can immediately grasp the actual situation in the tunnel, and then adjust the design and planning.

The high efficiency of 5G network also helps monitor the real-time conditions of the tunnel. For example, the real-time air monitoring device and UWB positioning watches are used separately to monitor air, temperature, luminosity, gas and the health status of workers in the tunnel, as well as the safety of the location. In case of a danger, an alarm will go off immediately. It greatly improves construction efficiency and ensures the safety of workers.

As the project is in full swing and the location of works is deeper into the mountain, more blasting works will be implemented for cavern in the future. More innovative technologies are required to improve the construction management and ensure the safety of workers. In the future, there will be higher requirements for volume of data, transmission speed and frequency. A stable and efficient 5G network is indeed an indispensable part of a safe and efficient construction site.