Noriyuki Okano

STUDY ON THE STRENGTH EVALUATION METHOD OF BRICKWORK LINING TUNNEL

It is necessary to estimate the strength of masonry tunnels to maintain these tunnels and assess the influence of adjacent construction work. However, the methods of calculation have not been established yet. The authors performed S=1/2 arch part tests of the brickwork lining tunnel to investigate the mechanical properties of them. Then they simulated the tests using the Beam-Spring Model Analysis. As a result, they concluded the followings: 1) the strength characteristics of tunnel lining made of brick and joint material have been revealed, 2) the joint material between the inner and outer layers should be considered for this Beam-Spring Model Analysis, and 3) from the parameter study on the actual brickworks on the railway single-truck tunnel, the brickwork lining becomes very weak if there is a shortage of section or a background void.

A Study on Numerical Simulation during Chemical Grouting

The chemical grouting has the advantages that equipments are small and the direction of boring has flexibility. Therefore, in Japan, it is frequently used for a soil-improvement method in the railway construction site where workspace or working hours is limited. However, it has the possibility to cause a ground displacement around the site. Because there is no method that estimates it quantitatively, the design based on old cases is still used mainly and focuses on safety overly. In this Study, the simplified numerical analysis for ground behavior due to the osmotic pressure during injection is proposed.