Test Research on Health Criterion of Cavities Behind the Lining

It’s very common that there are cavities after the lining and seriously affects the health of the tunnels. According to the status that the health standard is not uniform at present, the health levels can be divided into four parts: health, sub-health, disease and sick into death. For studying the single index criterion of lining cavities, and introducing lab large-scale model test combining the engineering example, analyzing the variety of structure bearing capacity, disease producing shapes and varying rule and so on where are different dimension cavities after lining. The results show that the carrying capacity curve expresses reverse S characteristic, it can be divided into slow, fast and complete degradation basis on the variety of velocity, and it is uniform to the sub-health, disease and sick into death, finding out the single health criterion of cavity: it is health where no cavities after the lining, it’s sub-health when the dimension is less than 100mm, disease when the dimension is between 100mm and 550mm, it’s sick to death if the dimension were more than 550mm.