Construction Scheme with Non-stop Aviation for Large-diameter Shield Tunnel Crossing Airport Flight Zone in Karst Area

Abstract

[Objective] To achieve non-stop aviation during the construction of a large-diameter shield tunnel crossing the airport flight zone in karst area, it is essential to study the construction scheme with non-stop aviation. [Method] Based on the construction of the No.2 and No.3 underpasses of the Phase III expansion project of Guangzhou Baiyun International Airport, the obstacle restrictions and runway land subsidence control requirements for non-stop aviation in airport flight zone are analyzed, and control standards for the runway area of this project are proposed. Combining the geological characteristics of engineering in karst area, a construction scheme for shallow-buried large-diameter shield tunnels is proposed. A three-dimensional refined numerical model is established to analyze the impact of shield tunneling on airport runway and validate the feasibility of the construction scheme. [Result & Conclusion] Efforts should be made to avoid tunneling into tunnel bottom bedrocks and meet the tunnel overall anti-floating requirements. Measures to increase shield tunnel overall stiffness should be taken to minimize the impact on airport operations to the greatest extent. The research results indicate that the design of tunnel crossing airport flight area mainly considers the impact of runway subsidence on aircraft operation safety during tunnel construction, so the runway subsidence control standard is set at the total subsidence within 30 mm, with a maximum differential subsidence rate not exceeding 1‰. According to numerical analysis results, the maximum subsidence of the airport runway during shield tunnel construction is 15.48 mm, with the maximum differential subsidence rate of 0.20‰, meeting the requirements for airport runway subsidence limits.

Keywords

• large-diameter shield
• karst area
• airport flight area
• construction with non-stop aviation