Application of Surface Quality Evaluation Method Based on Visual Inspection of Secondary Lining Concrete of NATM Tunnel and Approach to Surface Quality Improvement
By K. Watanabe, N. Sakata, A. Hosoda and K. Sato
Concrete Journal, Vol.57, No.8, Aug. 2019
- Synopsis
- The secondary lining concrete of a NATM tunnel is a difficult part of construction where the members are thin and concrete fills the enclosed space between the tunnel lining form and the ground. Owing also to the difficulty of construction, various deformations and malfunctions are sometimes found in the structures in use. In consideration of the above, various attempts have been made to improve the quality of new structures through application of the PDCA cycle, using methods to rationally evaluate the quality of the surface layer of lining concrete based on visual inspection. This report introduces cases of the analysis of the results of surface quality evaluation through visual inspection of the secondary lining concrete of some NATM tunnels built in the Tohoku region for the purpose of securing and improving quality.
- Keywords:
- lining concrete, surface quality, visual inspection, visual evaluation, PDCA
