Experimental Study on the Bonding Performances of Spray-applied Waterproofing Membrane in Tunnels with CSL Structure
(1. School of Railway Transportation, Shanghai Institute of Technology, Shanghai 201418; 2.Key Laboratory of Transportation Tunnel Engineering of Ministry of Education, Southwest Jiaotong University, Chengdu 610031; 3.School of Civil Engineering, Southwest Jiaotong University, Chengdu 610031)
Abstract:
In view of the serious problem of water leakage in tunnels, this paper adopts a new spray-applied water? proofing membrane technology to establish a form of tunnel composite shell lining (CSL) structure with bonding properties to both outer and inner concrete layer, thus overcoming the drawbacks of the traditional supporting structure of concrete layer with waterproofing boards in terms of waterproofing performance. The bonding performance between the spray-applied waterproofing membrane and the outer and inner concrete layer is an important parameter in the CSL design and directly decides the waterproofing and supporting performance of the CSL. In view of this, this paper carries out a bonding performance test on the spray-applied waterproofing membrane for the tunnel CSL structure, studies the impacts of dry and wet states of the shotcrete surface, and the membrane thickness on the CSL bonding performance. The research results show that the interlayer bonding strength is inversely proportional to the square root of the membrane thickness; Under the premise of no flowing water on the shotcrete surface, the waterbearing shotcrete surface helps to improve the bonding strength of the waterproofing membrane to the shotcrete and gives full play to its bonding properties; With the increase of the water content, the bonding strength of the CSL structure shows a gradual increase.
.Experimental Study on the Bonding Performances of Spray-applied Waterproofing Membrane in Tunnels with CSL Structure[J] MODERN TUNNELLING TECHNOLOGY, 2022,V59(1): 104-110