DURABILITY ASSURANCE METHODS OF REINFORCED CONCRETE SEGMENTS OF SHIELD TUNNELS FOR TRANSMISSION

Abstract

This paper proposes the durability assurance methods of shield tunnels for transmission which are assembled by reinforced concrete segments based on the degradation analysis of existing shield tunnels for transmission. The main features of these methods are the following three points.
First, we group the environmental conditions of these tunnels into seashore and inland atmosphere. Secondly, we propose thickness of minimum concrete cover to reinforcement of segment under both environmental conditions. Thirdly, we propose the allowable crack width against both environmental conditions to control cracks caused by bending force of the segments against the permanent loads.