Service Life Prediction of Lining Concrete for Jiaozhou Bay Subsea Tunnel
JIN Zu quan,ZHAO Tie jun,HOU Bao rong and LI Qiu y
DOI:10.11835/j.issn.1674-4764.2009.06.015
Received July 29, 2009,Revised , Accepted , Available online July 01, 2015
Volume ,2009,Pages 86-91
- Abstract
Jiaozhou Bay subsea tunnel is the second self built tunnel in China with the designed service life over 100 years. On the basis of service environment of subsea tunnel concrete and the durability experiments of concretes, the service life prediction model considering chloride diffusion, carbonation and bending loading was proposed. The key durability coefficient of lining concrete in subsea tunnel was investigated. And the function of chloride diffusion coefficient and rebound strength of concrete was proposed. Moreover, the chloride content in concrete varied with service time and the service life of lining concrete for subsea tunnel was predicted with the proposed service life prediction model. It was found that the value of varied cover thickness was from -4(6) to 15 mm. The chloride diffusion coefficient mean value of lining concrete in standard curing was 2.1(2.7)×10-12m2/s. And the initial chloride content in concrete was less than 0.35kg/m3. The relationship between chloride diffusion coefficient and rebound strength could be regressed to linear relationship, and the calculated chloride diffusion coefficient of lining concrete was varied from 1.5×10-12m2/s to 3.5×10-12m2/s. The predicted service life of lining concrete for Jiaozhou bay subsea tunnel was more than 100 years according to proposed model.