TY - JOUR
T1 - Design of a distributed optical fiber sensor system for measuring immersed tunnel joint deformations
AU - Zhang, Xuehui
AU - Broere, Wout
PY - 2023
Y1 - 2023
N2 - Monitoring the deformations of immersed tunnels is important during the entire tunnel service life to assess the structural integrity of the tunnel. Conventional joint deformation monitoring is based on manual levelling measurements and normally occurs only at multi-year intervals, which does not allow to capture short term deformation behavior. In this study a new joint monitoring system using distributed optical fiber sensors (DOFS) is developed. A special sensor layout is designed that allows simultaneous measurements of both horizontal joint opening and vertical uneven settlement of the immersion and dilation joints. For this sensor scheme the transfer relation from fiber strain to joint deformation is derived and verified by in-lab experiments. The sensor system proves to be able to detect sub-millimeter joint deformations, indicating a more than sufficient accuracy for structural monitoring of immersed tunnel joints. Subsequently, the First Heinenoordtunnel in the Netherlands is instrumented using this distributed optical fiber sensing system, in order to obtain additional data for both long-term and short-term assessment of its structural condition.
AB - Monitoring the deformations of immersed tunnels is important during the entire tunnel service life to assess the structural integrity of the tunnel. Conventional joint deformation monitoring is based on manual levelling measurements and normally occurs only at multi-year intervals, which does not allow to capture short term deformation behavior. In this study a new joint monitoring system using distributed optical fiber sensors (DOFS) is developed. A special sensor layout is designed that allows simultaneous measurements of both horizontal joint opening and vertical uneven settlement of the immersion and dilation joints. For this sensor scheme the transfer relation from fiber strain to joint deformation is derived and verified by in-lab experiments. The sensor system proves to be able to detect sub-millimeter joint deformations, indicating a more than sufficient accuracy for structural monitoring of immersed tunnel joints. Subsequently, the First Heinenoordtunnel in the Netherlands is instrumented using this distributed optical fiber sensing system, in order to obtain additional data for both long-term and short-term assessment of its structural condition.
KW - Distributed optical fiber sensor
KW - Immersed tunnel
KW - Joint deformation
UR - http://www.scopus.com/inward/record.url?scp=85139591524&partnerID=8YFLogxK
U2 - 10.1016/j.tust.2022.104770
DO - 10.1016/j.tust.2022.104770
M3 - Article
AN - SCOPUS:85139591524
SN - 0886-7798
VL - 131
JO - Tunnelling and Underground Space Technology
JF - Tunnelling and Underground Space Technology
M1 - 104770
ER -