Tweet Share

• Send by email

  Send by email

  

  Investigating the Causes of Cracks and the Repair of Precast Reinforced Concrete Segmental Lining of an Existing Rail Tunnel in Singapore

  Significant cracks on precast reinforced concrete segmental linings of bored tunnel were observed during a regular visual inspection of a rail tunnel. Investigations were carried out to establish the causes of tunnel damage as well as whether the cracks were active. Investigations revealed that the cracks on the segments were due to the consolidation of soft marine clay layer of the Kallang Formation, resulting in tunnel settlement and squat. Instrumentation and monitoring had also confirmed that the consolidation settlements have ceased and no further damage would be expected. Upon the discovery of cracks, the structural capacity of the cracked segments were reviewed, and calculations showed cracks of more than 2mm on segments could have caused the rebar in the segments to just start yielding. Thus, rectification works were carried out for two tunnel segment linings with significant cracks (2mm and 3mm wide). Stainless steel plates were installed on the intrados of the two cracked segments to restore the bending capacity.

  Recipient :

  Name ^* :

  E-mail address ^* :

  ^* Required fields

  Send   or  Cancel

• Print