Underground Singapore 2011
Plan of instrumentation at cut and cover tunnel
Typical section of cut and cover tunnel instrumentation
Figure 11窶的nstrumentation at Cut and Cover Tunnel
7.
PERFORMANCE OF EXISTING STRUCTURE
Monitoring result showed that the displacement of cut and cover tunnel remained relatively small, with maximum vertical settlement and horizontal displacements in the range of about 2 mm. Figure 12 and Figure 13 present 3D real time monitoring results. It can be concluded that the construction of connection tunnel did notChange cause in any to the existing CCL structures or caused concerns with dX damage at C825 Upper Tunnel_above DTL(SCL) respect to train operations. 12
A.L 70% A.L
6
dX(mm)
4
Start of DTL-U (SCL)
8
Start of DTL-L (SCL)
W.S.L
10
2 0 -2 -4
70% A.L
-6
A.L
-8 W.S.L
-10
XYZ8214
XYZ8215
XYZ8217
Figure 12窶天ertical settlement of upper cut and cover tunnel
150
XYZ8218
26-Sep-10
6-Sep-10
17-Aug-10
28-Jul-10
8-Jul-10
18-Jun-10
29-May-10
9-May-10
19-Apr-10
30-Mar-10
10-Mar-10
18-Feb-10
29-Jan-10
9-Jan-10
20-Dec-09
30-Nov-09
10-Nov-09
21-Oct-09
1-Oct-09
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